U.S. PATENT AND TRADEMARK OFFICE
Information Products Division |
U.S. Patent Classification System - Classification Definitions
as of June 30, 2000
Patents classified in a subclass may be accessed by either clicking on
the subclass number
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Classification Index
Explanation of Data web page.
(definitions have been obtained from the
Patents ASSIST CD-ROM which
is produced by the U.S. Patent and Trademark Office
Electronic Products Branch)
Class 327
MISCELLANEOUS ACTIVE ELECTRICAL NONLINEAR DEVICES, CIRCUITS,
AND SYSTEMS
Class Definition:
This is the residual class for electrical devices, circuits
or systems having an output not directly proportional to its
input and comprising at least one component which can provide
gain or can route electrical current and which device,
circuit or system does not form a complete system such as is
classified specifically elsewhere or a subcombination of
utility only in such elsewhere classified system.
(1) Note. The scope of patents classified herein can be
determined only by determining the scope of other related
classes which are listed below under SEARCH CLASS. Also,
consult search notes and definitions of these classes.
(2) Note. Typical active components are solid-state
components, vacuum tubes, and gas filled tubes. However,
also included would be components broadly claimed to have
active properties, but which are not specifically limited to
a particular embodiment such as a vacuum tube.
MAIN SUBDIVISIONS OF THIS CLASS
A. Specific Signal Discriminating (e.g., Comparing Or
Selecting) Without Subsequent Control
Included here are circuits for the comparison, selection, or
distinguishing of specific characteristics of either an input
signal or signals without continuous regulation of such
characteristic.
B. Signal Converting, Shaping, Or Generating
Included here are circuits wherein: (a) an inherent input
signal parameter such as phase, frequency, amplitude or
current is modified, maintained at some value, or changed to
an entirely different parameter; (b) an input signal having a
particular waveform modified into an output signal having a
partially or a completely different waveform; or (c) an
output signal of specified waveform is produced.
C. Specific Input To Output Function
Included here are circuits wherein an output signal is
proportional to a mathematical expression involving an input
signal or signals.
(1) Note. Characteristically, the input signals are
continuous and slowly varying.
(2) Note. Circuitry performing Boolean Algebra functions,
per se, are excluded from this class. See References to Other
Classes, below.
(3) Note. The input signals of this subclass do not contain
information (data). For data processing see References to
Other Classes, below.
D. Gating (i.e., Switching Input To Output)
Included here are electron tube or solid-state gating
circuits which distribute unmodified input signals to
selected outputs.
E. External Effect
Included here are circuits, not elsewhere classified
responsive to or compensating for an ambient nonelectrical
condition such as heat or magnetism.
F. With Particular Control
Included here are circuits where current or power to a
broadly recited device is controlled in response to a control
signal. The control signal may be derived from an external
source or from a feedback structure responsive to the
condition of the load.
(1) Note. Where a specific load device is recited,
classification will be in the particular class providing for
the specific load device.
G. Specific Identifiable Device, Circuit, Or System
Included here are circuits having a particular structure,
arrangement, or construction not classifiable elsewhere.
H. Miscellaneous
Included here are systems or circuits not provided for
elsewhere.
LINES WITH OTHER CLASSES AND WITHIN THIS CLASS
ACTIVE FILTERS
The filters proper for this class include at least one active
device utilized in producing the transfer function defining
the frequencies that will be passed.
A filter in combination with a specific load will be
classified in the class providing for the load. See
References to Other Classes, below for filtering of data
within an electrical digital calculating computer or analog
computer.
The filters within the Specific Identifiable Device, Circuit,
Or System area (see above) are active filters that suppress
an unwanted input signal. See Noise Filters below for
additional noise filter areas within Class 327.
NOISE FILTERS
Limiting, clipping, or clamping circuits which achieve
transient or signal noise reduction by filtering or otherwise
are classified in this class.
Compensation for a noise signal which is a by-product of
switching thereof is found in this class.
Miscellaneous unwanted signal suppression is classified in
this class.
See Subclass References to the Current Class below for these
art areas.
PHASE LOCK LOOP
A nonlinear phase lock loop circuit, per se, is classified in
Class 327. A phase lock loop circuit in combination with a
special art device, is classified with the special art
device. For example, a phase lock loop claimed in
combination with an oscillator is classified in Class 331,
subclasses 172+, a phase lock loop in combination with a
telecommunication system is classified in Class 455, and a
phase lock loop in combination with a pulse or digital
communication system is classified in Class 375, subclasses
111+.
See Subclass References to the Current Class below for a
phase lock loop to synchronize one signal with another for
the creation of a replica signal.
DIGITAL LOGIC
Digital logic, per se, is classified in Class 326 and this
includes, for example, multiple connections of AND, OR, or
NOT gates. However, combinations of multiple AND or OR
gates, etc., which perform a particular function proper to
some other class are classified in that other class. For
example, an AND gate claimed to be used as a comparator, for
example, will be classified in Class 327, whereas a claimed
AND gate, per se, would be classified in Class 326.
MULTIVIBRATOR
Patents reciting a free running astable multivibrator, per
se, are classified elsewhere. For example, see References to
Other Classes for a relaxation oscillator multivibrator.
Multivibrators having one or more stable states are
classified in Class 327. See Subclass References to the
current Class.
Generally, detailed flip-flops, per se, are in this class,
subclasses 185+; however, multifunctional or programmable
logic having a flip-flop is in Class 326, subclasses 37+ and
redundant logic having a flip-flop is in Class 326, subclass
12.
INTEGRATED STRUCTURE
An integrated circuit chip, per se, is classified in Class
257.
Lead frames, per se, are classified in Class 257 since these
are only used to connect an integrated circuit chip
externally.
An integrated circuit chip in combination with a single lead,
a battery or bias without any additional circuit
configuration, is classified in Class 257.
An integrated circuit chip in combination with an external
circuit proper for Class 327 will be classified in Class 327
since Class 327 is higher than Class 257 in the overall class
hierarchy.
Circuit interconnections (e.g., point to point, lead
interconnections, diode and transistor interconnections,
etc.) within the confines of the integrated circuit chip
itself are classified in Class 257, whereas circuit
interconnections outside the environment of an integrated
circuit chip are not.
If an integrated circuit is recited with other than a nominal
recitation of a utility, the patent will be classified in the
utility class.
CHARGE COUPLED DEVICES
CCD's recited as part of the circuitry within an integrated
circuit chip are classified in Class 257.
CCD's recited with other than a nominal recitation of utility
are classified in the utility class. See References to Other
Classes, below.
POWER SUPPLIES
Power supplies in combination with another art device,
classifiable elsewhere, will be found with the other art
device. Tubes or solid-state device power supplies for a
nonlinear device, circuit, or system, not elsewhere
classified, will remain in this class (327).
A power supply in combination with a load, (i.e., a single
power supply and a single load) without any claim to a
substrate circuit is classified elsewhere. See References to
Other Classes, below.
The power supply patents of this class, subclasses 530+
require a nonlinear device, circuit, or system as a load or
control for the power supply. A claim to a power supply
circuit in combination with a substrate containing a
nonlinear device, circuit, or system is classified in Class
327.
SYSTEMS WITH SPECIFIC SOURCE OF INPUT ENERGY ONLY IDENTIFIED
BY CHARACTERISTIC
This class does not provide for the subject matter included
herein in combination with a specific type of electromagnetic
wave energy since the broad recitation of the specific source
would be classifiable with the art containing that particular
source of energy. However, this class will take the systems
and networks of the class in combination with a source of
wave energy wherein the energy is expressed only as being
composed of a band of frequencies or a source of pulses,
etc., or wherein the source is recited by name only as a wave
energy generator (such as an oscillator, pulse generator,
etc.). Where the specific details of the source are recited
such systems are classified with the art which provides for
systems utilizing such specific source.
MECHANICAL STRUCTURE
Claims to a specific mechanical structure in combination with
generic circuitry are classified with the mechanical
structure. However, claims to broad mechanical structure in
combination with specific circuitry is classified in this
class unless provided for in a mechanical or electrical class
and provided the circuitry is nonlinear.
MEMORY CIRCUIT
A generic nonlinear circuit claimed with a memory inside the
circuit is classified in this class (327), whereas a claim to
generic circuitry in combination with a memory external to
the circuit would be classified with the memory class.
MONITORING, TEST OR CALIBRATING
The following areas reciting monitoring, testing or
calibrating take precedence over Class 327:
Class 73, subclasses 1.01+ for instrument proving or
calibrating; and subclass 865.9 for testing of apparatus.
Class 324, subclass 601 for calibration, and subclasses 74+
for testing and calibrating of electric meters.
Class 342, subclasses 165+ for testing or calibrating a radar
system.
Class 348, subclasses 180+ for television monitoring or
testing.
Class 358, subclass 406 for facsimile measuring or testing.
Class 364, subclasses 571.01+ for testing and measuring which
includes a computation.
Class 374, subclasses 1+ for thermal measuring and testing.
Class 455, subclass 115 for measuring, testing or monitoring
of a transmitter and subclass 226 for measuring, testing, or
monitoring of a receiver. Only monitoring, testing, or
calibrating, not elsewhere classified, and related to
nonlinear devices, circuits and systems are classified in
Class 327. The following are examples of those found in
Class 327: subclasses 20, 262, 292, 378, 509, and 538.
Class 600, subclass 486 for testing means inserted in the
human body.
FUNCTION
Only those nonlinear circuits or systems whose function is
not specifically provided for elsewhere would be classified
in this class (327) subclasses 334+.
SWITCHING
See References to Other Classes, below for examples of other
areas for switching;
CIRCUITS WITH ELECTRON OR OTHER CHARGED PARTICLE BEAM TUBE
Only those nonlinear circuits utilizing electron or other
charged particle beams that are not classifiable in other
areas would be classified in Class 327.
Examples of electron or other charged particle beam tube
circuits classified elsewhere are the cyclotron and CRT
circuits of Class 313.
MODULATION OR COMMUNICATION
Nonlinear circuits used in combination with a modulated
signal are classified in the classes containing the
communication of information via a modulated signal.
ELECTRICAL CONTROL OF MACHINES
Electrical control with a broad machine is classified with
the machine, if a class exists for the machine. Only those
electrical control patents, not provided for in the machine
classes, would be classified in Class 327, provided the
circuit is nonlinear.
NEURON CIRCUITS OR NETWORKS
Patents reciting neuron simulator circuitry, per se, and
neural networks are classified elsewhere. See References to
Other Classes below.
FUSIBLE LINK AND INTENTIONAL DESTRUCT CIRCUIT
Miscellaneous circuits of this type are classified in this
class (327) subclass 525.
OSCILLATORS
Free running oscillators (including the asynchronous type)
are classified elsewhere. See References to Other Classes
below.
PERSONNEL OR DEVICE PROTECTIVE CIRCUITS
Circuits used to protect personnel from harm, or protect
devices from failure (e.g., overload, power surge) are
excluded from this class. See References to Other Classes
below.
SYSTEMS WITH SPECIFIC LOADS IN THE OUTPUT CIRCUIT
This class does not provide for the subject matter in
combination with a specific load device even though the load
device is recited by name only (as a motor, loud-speaker,
etc.). Such systems are classified in general with the
particular art device constituting the load.
AMPLIFIERS
This class does not include electronic circuits, per se,
wherein a variable electric current or voltage input signal
is applied to an electrical amplifying device to control a
source of electrical energy applied to the same device, and
from which is derived an output signal of substantially the
same waveform as the input signal and substantially linearly
related thereto.
LINEAR DEVICE, CIRCUITS OR SYSTEMS
This class excludes linear resistors, reactive apparatus and
insulators, per se. Although the claimed solid-state device
may be active or passive and have some insulative or reactive
properties, it cannot be classified in this class if the
device is generally thought of as being only an insulator or
reactive apparatus such as a capacitor, inductor,
transformer, motor, etc.
COUNTERS
See References to Other Classes for electrical pulse
counters, pulse dividers, or shift registers.
PASSIVE FILTERS
See References to Other Classes for filters utilizing lumped
or distributed parameter passive elements.
SPECIAL ART DEVICES
Special art devices are to be classified with the specified
device.
GAS TUBE
Circuitry utilizing gas tubes not elsewhere provided for are
included here. See, Subclass References To The Current
Class, below, for an example.
SEE OR SEARCH THIS CLASS, SUBCLASS:
147 156+ provide for a phase lock loop to synchronize one
signal with another for the creation of a replica signal.
185 for multivibrators having one or more stable states.
310 for limiting, clipping, or clamping circuits which
achieve transient or signal noise reduction by filtering or
otherwise. (see "Noise Filters" above)
379 for compensation for a noise signal which is a
by-product of switching thereof. (see "Noise Filters" above)
551 for miscellaneous unwanted signal suppression. (see
"Noise Filters" above).
601 for circuitry utilizing gas tubes (see "Gas Tube"
above)
REFERENCES TO OTHER CLASSES
SEE OR SEARCH CLASS:
73, Measuring and Testing, appropriate subclasses for systems
and apparatus for making a measurement or test not provided
for in other classes, particularly 1.01 for instrument
proving or calibrating, and subclass 865.9 for testing of
apparatus.
84, Music, 600 for electrical musical tone generation using
transistors or space discharge devices.
136, Batteries: Thermoelectric and Photoelectric
appropriate subclasses.
148, Metal Treatment, 33 for barrier layer stock material.
174, Electricity: Conductors and Insulators, appropriate
subclasses for the physical structure of conductors.
178, Telegraphy, appropriate subclasses for telegraph
apparatus and systems, particularly subclass 43 for space
induction systems, and subclasses 66.1+ for alternating or
pulsating current telegraph systems.
191, Electricity: Transmission to Vehicles, appropriate
subclasses.
200, Electricity: Circuit Makers and Breakers, appropriate
subclasses for electric switches and circuit breakers and for
electrical and mechanical switches.
204, Chemistry: Electrical and Wave Energy, appropriate
subclasses for apparatus for producing chemical changes
through the agency of electrical wave energy.
219, Electric Heating, subclasses 600-780 for induction,
electro-static or electro-magnetic heating systems and
subclass 114 for welding circuits with space discharge tube
control.
246, Railway Switches and Signals, appropriate subclass for
electric circuits utilized in railway switches and signals.
250, Radiant Energy, appropriate subclasses for the detection
of nuclear or electromagnetic radiant energy, the testing of
material by nuclear or electromagnetic radiant energy, the
irradiation of material by nuclear or electromagnetic radiant
energy, electron energy analysis, the deflection or focussing
of an ion or electron beam, and the generation of control of
nuclear or electromagnetic radiant energy.
252, Compositions, 62.3 for barrier layer compositions and
subclasses 500+ for other semiconductor compositions.
257, Active Solid-State Devices (e.g., Transistors,
Solid-State Diodes), appropriate subclasses for particular
nonlinear solid-state devices, per se, also for an integrated
circuit chip, per se, and for lead frames, per se, since
these are only used to connect an integrated circuit chip
externally. An integrated circuit chip in combination with a
single lead, a battery or bias without any additional circuit
configuration is classified in Class 257.
290, Prime-Mover Dynamo Plants, appropriate subclass for
electric circuits utilized in prime mover dynamo plants.
307, Electrical Transmission or Interconnection Systems,
appropriate subclasses for circuits providing electrical
transmission or interconnection such as those having plural
energy sources or plural loads and class appropriate
switching systems, wave form determinative networks, and
circuits responsive to external effects such as temperature
or magnetism.
307, Electrical Transmission or Interconnection Systems, 326
for circuits used to protect personnel from harm, or protect
devices from failure (e.g., overload, power surge). (see
"Personnel Or Device Protective Circuits" above)
310, Electrical Generator or Motor Structure, appropriate
subclasses for the physical structure of electric generators
and motors and electromagnetic clutches and for the circuits
that relate to electromagnetic clutches, and particularly 314
for piezoelectric devices in combination with tube structure
where the significant structure claimed is that of the
crystal, and the tube structure or circuitry is only
incidentally claimed.
313, Electric Lamp and Discharge Devices, appropriate
subclasses for the physical structure of electronic lamp and
discharge devices, per se.
314, Electric Lamp and Discharge Devices: Consumable
Electrodes, appropriate subclasses for electric lamp and
discharge devices of the arc discharge type which may be
combined with an electron space discharge tube.
315, Electric Lamp and Discharge Devices: Systems,
appropriate subclasses for circuits in combination with
charged particle beam tubes, cathode-ray tubes or electric
lamp and space discharge devices, particularly 8.51 for
pulse storage systems utilizing cathode-ray tubes, and
subclasses 84.51+ for pulse storing systems comprised
exclusively of gaseous discharge tubes.
318, Electricity: Motive Power Systems, 677 for electric
motor position servomechanisms utilizing electron space
discharge apparatus; subclasses 126+ for energizing of
winding circuit control responsive to condition, pulsed
energy etc.; subclass 132 which relates to space discharge or
unidirectionally conductive devices in a winding control
circuit; subclass 138 for a space discharge device commutated
motor; and subclasses 505+, 732, 752, 756, and 786 for motor
control systems utilizing space discharge devices.
320, Electricity: Battery or Capacitor Charging or
Discharging, appropriate subclass for a battery or capacitor
charging or discharging application that employs a
space-discharge device.
322, Electricity: Single Generator Systems, 72 for electron
space discharge tube systems for controlling a single
generator.
323, Electricity: Power Supply or Regulation Systems,
appropriate subclasses for circuits utilized in power voltage
magnitude and phase control systems.
323, Electricity: Power Supply Or Regulation Systems, for a
power supply in combination with a load, (i.e., a single
power supply and a single load) without any claim to a
substrate circuit (See "Power Supplies" above)
324, Electricity: Measuring and Testing, appropriate
subclasses for circuits utilized in electrical measuring,
testing, and sensing systems.
326, Electronic Digital Logic Circuitry, appropriate
subclasses for combinational or sequential logic, per se.
326, Electronic Digital Logic Circuitry, for circuitry for
performing Boolean Algebra functions, per se. (see Class
Definition, "Specific Input To Output Function" above)
326, Electronic Digital Logic Circuitry, for a logical
function (see "Charge Coupled Devices" above)
327, Miscellaneous Active Electrical Nonlinear Devices,
Circuits, and Systems, for delay (see "Charge Coupled
Devices" above)
329, Demodulators, appropriate subclasses for circuits
extracting information from a carrier.
330, Amplifiers, appropriate subclasses for electron space
discharge tube apparatus combined with circuitry to form an
amplifier system and 250 for semiconductor amplifiers.
331, Oscillators, appropriate subclasses for electron space
discharge tube or solid-state apparatus combined with tuned
circuit apparatus forming an oscillatory system of the
self-sustaining type, an asynchronous oscillator, per se, or
in combination with other circuitry or an oscillator combined
with a phase lock loop without any intelligence claimed; 8
for transistorized automatic frequency control for
oscillators; and subclasses 108+ for solid-state
oscillators.
331, Oscillators, subclass 144 for a relaxation oscillator
multivibrators.
331, Oscillators, for free running oscillators (including the
asynchronous type). (see "Oscillators," above)
332, Modulators, appropriate subclasses for circuitry which
superimposes information on a carrier.
333, Wave Transmission Lines and Networks, subclass 19 for
passive element wave differentiating or integrating systems,
subclasses 24+ for passive filters, and subclass 20 for wave
shaping networks of the passive element type; subclasses
167+, 186+, and 202+ for filters utilizing lumped or
distributed parameter passive elements.
334, Tuners, appropriate subclasses for tuning circuitry.
335, Electricity: Magnetically Operated Switches, Magnets,
and Electromagnets, appropriate subclasses for magnetically
operated switches and circuit breakers.
336, Inductor Devices, appropriate subclasses for passive
inductive devices.
337, Electricity: Electrothermally or Thermally Actuated
Switches, appropriate subclasses for thermal switches, per
se.
340, Communications: Electrical, subclass 146.2 for digital
comparator systems, subclass 825.97 for electron beam type
selective or remote control systems, subclass 825.57 for
pulse responsive selective systems, subclass 825.67 for pulse
responsive counting chains which may employ an electron space
discharge device, and subclasses 870.01+ for telemetering
systems. (also see "Charge Coupled Devices" above)
348, Television (see "Charge Coupled Devices" above)
341, Coded Data Generation or Conversion, 50 for code
converters and subclasses 20+, 186, and 191 for a pulse
transmitter or generator having a space discharge device.
342, Communications: Directive Radio Wave Systems and
Devices (e.g., radar, Radio Navigation), appropriate
subclasses for systems for object detection and utilizing
pulse radio wave forms and subclass 165 for testing or
calibrating a radar system.
343, Communications: Radio Wave Antennas, appropriate
subclasses for antennas, per se.
348, Television, 180 for television monitoring or testing.
352, Optics: Motion Pictures, 1 for sound accompanied
motion pictures including active electronic devices.
356, Optics: Measuring and Testing, 3 for systems using
light for distance finding and subclasses 26+ for light
systems for the determination of velocity.
358, Facsimile and Static Presentation Processing, subclass
406 for facsimile measuring or testing.
359, Optics: Systems (Including Communication) and Elements,
appropriate subclasses for optical components.
360, Dynamic Magnetic Information Storage or Retrieval,
appropriate subclasses.
361, Electricity: Electrical Systems and Devices, 1 for
safety and protection of systems and devices, subclasses 100+
for current fault sensor with semiconductor circuit
interrupter, subclasses 139+ for control circuits for
electromagnetic devices, and subclasses 196+ for control
circuits for electromagnetic devices with time delay
including a semiconductor device.
361, Electricity: Electrical Systems and Devices, 1 for
circuits used to protect personnel from harm, or protect
devices from failure (e.g., overload, power surge). (see
"Personnel Or Device Protective Circuits" above)
363, Electric Power Conversion Systems, appropriate
subclasses for circuits utilized in electric conversion
systems where a single electrical source is connected to a
single electrical load and particularly subclass 94, 99,
111+, 151, and 166 for systems whereby a current or voltage
of one characteristic is converted to a current or voltage of
another characteristic and utilizing electron space discharge
devices.
365, Static Information Storage and Retrieval, 73 for
recirculation of information in a storage read/write system,
subclass 78 for plural shift register memory devices,
subclasses 80+ for magnetic shift register, per se,
subclasses 129+ for storage systems using a particular
storage element, subclasses 189.01+ for read/write circuits
peculiar to a storage and retrieval system, and subclasses
230.01+ for addressing circuits peculiar to a storage and
retrieval system. (also see "Charge Coupled Devices" above)
367, Communications, Electrical: Acoustic Wave Systems and
Devices, appropriate subclasses.
369, Dynamic Information Storage or Retrieval, appropriate
subclasses.
370, Multiplex Communications, appropriate subclasses for
multiplexing systems.
373, Industrial Electric Heating Furnaces, subclass 70, 102+,
135+, and 147 for electric furnaces having significant
electrical circuits.
374, Thermal Measuring and Testing, 1 for thermal
calibration.
375, Pulse or Digital Communications, 106 for digital
communication synchronization.
377, Electrical Pulse Counters, Pulse Dividers, or Shift
Registers: Circuits and Systems, appropriate subclasses for
electrical pulse counters, dividers, and shift registers and
particularly 57 for charge coupled devices used as a
counter, pulse divider, or shift register. (also see "Charge
Coupled Devices" above)
378, X-Ray or Gamma Ray Systems or Devices, 91 for circuits
combined withX-ray devices.
379, Telephonic Communications, appropriate subclasses, for
telephone systems.
380, Cryptography, appropriate subclasses for cryptos:graphic
circuitry.
381, Electrical Audio Signal Processing Systems and Devices,
94.1 for noise suppressing audio circuitry and subclass 111
for circuitry combined with a specific type of microphone or
loudspeaker.
382, Image Analysis, appropriate subclasses.
388, Electricity: Motor Control Systems, art collection 913
for motor control systems including space discharge devices.
396, Photography, appropriate subclasses for apparatus
producing pictures on light sensitive material which may
utilize electronic devices. (also see "Charge Coupled
Devices" above)
427, Coating Processes, 58 for coating processes wherein an
electrical product is produced.
428, Stock Material or Miscellaneous Articles, subclass 620
for semiconductor stock material.
438, Semiconductor Device Manufacturing: Process, for
methods of making semiconductor electrical devices; see the
search notes thereunder.
445, Electric Lamp or Space Discharge Component or Device
Manufacturing, appropriate subclasses for circuits utilized
in the manufacture or repair of electric lamp or electric
space discharge devices.
455, Telecommunications, appropriate subclasses for
telecommunication systems and subsystems.
600, Surgery, 300 for diagnostic apparatus utilizing
transistors or tubes.
702, Data Processing: Measuring, Calibrating, or Testing,
appropriate subclasses for testing and measuring which
includes significant data processing.
706, Data Processing: Intelligent Processing Systems and
Methods, 15 for neural circuits and networks. (see "Neuron
Circuits Or Networks" above)
708, Electrical Computers: Arithmetic Processing and
Calculating, 300 for digital filters unique to digital
computing, subclass 540 for the performance of arithmetic
operations by a CRT, subclass 819 for analog filters which
are unique to analog computing, and subclass 849 for analog
function generation which utilizes a CRT. (See "Active
Filters", above.)
714, Error Detection/Correction and Fault Detection/Recovery,
appropriate subclasses.
SUBCLASSES
Subclass:
1
SPECIFIC SIGNAL DISCRIMINATING (E.G., COMPARING, SELECTING,
ETC.) WITHOUT SUBSEQUENT CONTROL:
This subclass is indented under the class definition.
Subject matter wherein an output signal is derived from one
or more input signals by comparing, selecting, or
distinguishing a particular input signal parameter and which
parameter is not continuously thereafter regulated.
SEE OR SEARCH THIS CLASS, SUBCLASS:
100 for signal converting, shaping, or generating which may
include control of the type of signal parameters found
herein.
SEE OR SEARCH CLASS:
250, Radiant Energy, subclass 250 for wave meters,
subclasses 281+ for systems adapted for ionic separation or
analysis and comprising phase or frequency determining
devices.
318, Electricity: Motive Power Systems, subclass 683 for
electric motor position servomechanisms involving phase
comparison devices.
322, Electricity: Single Generator Systems, subclass 32 for
automatic frequency control for generator systems.
323, Electricity: Power Supply or Regulation Systems, 212
for automatic phase control systems restricted to power
circuits.
324, Electricity: Measuring and Testing, 76.39 for
frequency measuring or testing of electricity and subclasses
76.77+ for phase comparison systems for measuring or testing
electricity and involving plural inputs.
329, Demodulators, appropriate subclasses for demodulators of
signals which have been modulated by an intelligence signal.
340, Communications: Electrical, subclass 146.2 for digital
comparator systems, subclasses 315, 825.06+, and 870.18+ for
electrical circuits whereby an indication or signal is
transmitted to a distant point and which signal is indicative
of an electrical condition which may comprise phase or
frequency difference.
361, Electricity: Electrical Systems and Devices, 236 for
speed-controlled systems involving phase or frequency
determining devices.
375, Pulse or Digital Communications, 106 for
synchronization in digital communications.
455, Telecommunications, 130 for a telecommunication
receiver.
714, Error Detection/Correction and Fault Detection/Recovery,
appropriate subclasses for error detection or correction of
information content of a digital signal.
Subclass:
2
By phase:
This subclass is indented under subclass 1. Subject matter
wherein the discriminated input signal parameter is that
fractional part of a periodic waveform which has elapsed
relative to a fixed origin.
(1) Note. If the time for one signal period is represented
as 360 degrees along a time axis, the phase position is
called the phase angle.
SEE OR SEARCH THIS CLASS, SUBCLASS:
39 for frequency comparison circuits.
231 for phase correction or control.
261 for output waveform production delay.
SEE OR SEARCH CLASS:
303, Fluid-Pressure and Analogous Brake System, 91 for
speed-controlled vehicle systems.
329, Demodulators, 345 for phase angle demodulation in which
a intelligence signal is extracted.
331, Oscillators, 1 for systems for stabilizing the
frequency of an oscillator utilizing phase or frequency
comparison devices, and subclasses 37+ for systems wherein
two or more frequencies are combined to produce a beat
frequency.
332, Modulators, 144 for systems wherein the phase of a
carrier wave is modulated by an arbitrarily varying
quantity.
455, Telecommunications, 214, for frequency or phase
modulation with particular discrimination or detection.
Subclass:
3
Comparison between plural inputs (e.g., phase angle
indication, lead-lag discriminator, etc.):
This subclass is indented under subclass 2. Subject matter
wherein the output signal is indicative of the phase
positioning or phase differences among two or more input
signals.
(1) Note. Detectors producing an output which is a result
of demodulation of a carrier having previously been modulated
by an intelligence waveform which varies arbitrarily will not
be classified here. See SEARCH CLASS below.
SEE OR SEARCH THIS CLASS, SUBCLASS:
40 for comparison between plural input frequencies.
SEE OR SEARCH CLASS:
329, Demodulators, 345 for circuits producing an output
which is a result of demodulation of a carrier having
previously been phase modulated by an intelligence waveform.
363, Electric Power Conversion Systems, appropriate
subclasses for phase conversion circuits with phase angle
sensing.
455, Telecommunications, 130 for mixers or converters
utilized in a superheterodyne receiver (commonly referred to
as a first detector).
Subclass:
4
With transducer:
This subclass is indented under subclass 3. Subject matter
wherein a device is included that converts energy forms other
than electrical into electrical energy.
(1) Note. The other energy forms may be mechanical,
thermal, hydraulic, or chemical, etc.
Subclass:
5
With input derived from feedback:
This subclass is indented under subclass 3. Subject matter
wherein a portion of the output signal is returned to one of
the plural inputs.
Subclass:
6
With electron space discharge:
This subclass is indented under subclass 3. Subject matter
including a vacuum tube device or a gaseous medium within a
gas tight envelope in which electron conduction takes place
through the vacuum or gas.
Subclass:
7
With reference signal:
This subclass is indented under subclass 3. Subject matter
wherein a signal of fixed phase acts as a constant for
comparison to a variable input.
(1) Note. The reference signal is usually an input signal
or produced from an input signal.
SEE OR SEARCH THIS CLASS, SUBCLASS:
42 for frequency comparison between a fixed reference
frequency and a variable input.
Subclass:
8
With varying frequency:
This subclass is indented under subclass 7. Subject matter
wherein the reference signal varies over a range of different
frequencies or the reference signal is compared to different
frequency signals.
Subclass:
9
With sampling:
This subclass is indented under subclass 7. Subject matter
wherein a reference signal is derived by representation of an
input signal at intermittently timed intervals.
SEE OR SEARCH THIS CLASS, SUBCLASS:
91 for details of sampling or holding in general.
Subclass:
10
Uniform pulse waveform:
This subclass is indented under subclass 7. Subject matter
wherein the reference signal is a series of pulses evenly
spaced.
SEE OR SEARCH THIS CLASS, SUBCLASS:
42 for a frequency comparison between a fixed reference
frequency and a variable input.
Subclass:
11
With transformer:
This subclass is indented under subclass 7. Subject matter
wherein an electromagnetic induction device transfers
electrical energy from one circuit to another adjacent
circuit at a constant frequency.
(1) Note. A transformer changes voltage in direct
proportion to the ratio of the number of turns of its primary
and secondary windings.
SEE OR SEARCH CLASS:
336, Inductor Devices, appropriate subclasses for transformer
details.
Subclass:
12
With logic or bistable circuit:
Subject matter under 3 wherein the phase comparison (a)
includes a device performing Boolean functions such as AND,
OR, or exclusive-OR or (b) utilizes a device having two
stable states.
(1) Note. The combination of logic with specific phase
comparison circuitry or function, not elsewhere classified is
classified here.
SEE OR SEARCH THIS CLASS, SUBCLASS:
185 for particular stable state circuits including
bistable.
SEE OR SEARCH CLASS:
326, Electronic Digital Logic Circuitry, 93 for clocking or
synchronizing of one or more logic stages and appropriate
subclasses for general digital logic circuitry not classified
elsewhere.
331, Oscillators, subclass 1 for automatic frequency control
synchronization with logic elements.
Subclass:
13
By shape:
This subclass is indented under subclass 1. Subject matter
wherein input signal discriminating is based upon a
predetermined geometric configuration.
SEE OR SEARCH THIS CLASS, SUBCLASS:
134 for sawtooth or triangular wave producing systems with
slope or duration control.
172 for pulse signal shaping with duration or width
control.
SEE OR SEARCH CLASS:
348, Television, 525 for sync separating systems which may
depend upon differences in the slope or shape of the input
pulses.
455, Telecommunications, 296 for static or noise elimination
in radio receivers which may depend upon the slope or shape
of the pulse present in the input signal applied to the
receiver.
Subclass:
14
Slope:
This subclass is indented under subclass 13. Subject matter
wherein the predetermined geometric configuration is signal
rate of change.
(1) Note. The rate of change may be determined by digital
means (such as counters) or analog means (such as slope
detection using a charging capacitor).
SEE OR SEARCH THIS CLASS, SUBCLASS:
134 for sawtooth or triangular waveform generation with
slope control.
170 for slope control of a pulse or clock waveform.
261 for output waveform production delay.
335 for the miscellaneous determination of the derivative of
an input signal.
Subclass:
15
With direction (i.e., positive or negative):
This subclass is indented under subclass 14. Subject matter
wherein the output signal indicates an upward or downward
inclination of the input.
Subclass:
16
Having feedback:
This subclass is indented under subclass 13. Subject matter
wherein a portion of the output signal is returned to an
input.
Subclass:
17
With reference signal:
This subclass is indented under subclass 13. Subject matter
wherein a signal of predetermined shape acts as a constant
for comparison to a variable input.
Subclass:
18
By presence or absence pulse detection:
This subclass is indented under subclass 1. Subject matter
wherein an output signal is indicative of an unexpected
occurrence or lack of occurrence of a pulse in either a
clocking signal or a predetermined sequence of pulses.
Subclass:
19
Arbitration:
This subclass is indented under subclass 18. Subject matter
wherein a particular pulse among plural pulses input during a
particular time interval is selected based upon a
predetermined priority arrangement.
SEE OR SEARCH THIS CLASS, SUBCLASS:
3 for phase discrimination.
Subclass:
20
Monitoring (e.g., failure detection, etc.):
This subclass is indented under subclass 18. Subject matter
wherein the detection of an undesired absent or present pulse
produces an output signal which indicates a failure.
SEE OR SEARCH THIS CLASS, SUBCLASS:
292 for clock fault compensation.
Subclass:
21
With variable frequency source:
This subclass is indented under subclass 18. Subject matter
wherein the absent or present pulse is detected from a
varying frequency input signal.
Subclass:
22
By pulse noncoincidence:
This subclass is indented under subclass 1. Subject matter
wherein an output signal is produced when two or more input
pulses are not received simultaneously.
Subclass:
23
By pulse coincidence:
This subclass is indented under subclass 1. Subject matter
wherein an output signal is produced when two or more input
pulse signals occur simultaneously.
SEE OR SEARCH CLASS:
326, Electronic Digital Logic Circuitry, 104 for circuits
performing fundamental Boolean Algebra functions, especially
the "AND" function.
Subclass:
24
Edge sensing:
This subclass is indented under subclass 23. Subject matter
wherein a beginning or trailing end of a pulse is determined
to occur simultaneously with a corresponding beginning or
trailing end of another pulse.
Subclass:
25
With uniform spacing:
This subclass is indented under subclass 23. Subject matter
wherein an output signal is produced when two or more input
pulse signals having the same time interval between
consecutive pulses occur simultaneously.
SEE OR SEARCH THIS CLASS, SUBCLASS:
31 for detecting a pulse width or spacing in general.
Subclass:
26
With pulse width detecting:
This subclass is indented under subclass 23. Subject matter
wherein pulse width discriminating is achieved via a pulse
coincidence operation.
SEE OR SEARCH THIS CLASS, SUBCLASS:
31 for detecting pulse width or spacing in general.
SEE OR SEARCH CLASS:
329, Demodulators, subclass 312 for a pulse width
demodulator.
Subclass:
27
With reference:
This subclass is indented under subclass 23. Subject matter
wherein an input pulse signal is compared with a
predetermined standard signal.
Subclass:
28
By polarity:
This subclass is indented under subclass 1. Subject matter
wherein the input signal parameter is its positive or
negative orientation with respect to a fixed origin.
Subclass:
29
Selection of a particular polarity:
This subclass is indented under subclass 28. Subject matter
wherein only a predetermined polarity of an input signal is
chosen.
Subclass:
30
Opposite polarity:
This subclass is indented under subclass 28. Subject matter
wherein an output signal results from comparing pulses which
have or are expected to have differing polarities.
Subclass:
31
By pulse width or spacing:
This subclass is indented under subclass 1. Subject matter
wherein the input signal parameter is (a) a time interval
between a leading edge and a trailing edge of a single pulse
or (b) a time interval between a trailing edge and a leading
edge of two consecutive pulses.
SEE OR SEARCH THIS CLASS, SUBCLASS:
172 for pulse signal shaping with duration or width
control.
SEE OR SEARCH CLASS:
340, Communication: Electrical, subclass 825.63 for pulse
width selective actuation and subclass 825.64 for pulse
spacing selective actuation.
Subclass:
32
With shock-excited circuit:
This subclass is indented under subclass 31. Subject matter
including a resonant circuit which oscillates at its natural
frequency upon application of an electrical impulse.
SEE OR SEARCH THIS CLASS, SUBCLASS:
596 for miscellaneous circuitry containing shock excited
resonant components.
SEE OR SEARCH CLASS:
331, Oscillators, appropriate subclasses for free running
generators utilizing shock excited resonant circuits.
334, Tuners, appropriate subclasses for tuned networks for
use in wave energy apparatus and comprising inductance and
capacitance elements in circuit arrangement to form a
resonant circuit and in which structure is provided for
adjusting one or both of these elements for changing the mean
resonant frequency of the circuit.
Subclass:
33
With sampling:
This subclass is indented under subclass 31. Subject matter
including a circuit providing periodic representations of an
input signal.
SEE OR SEARCH THIS CLASS, SUBCLASS:
9 for phase discriminating with sampling.
91 for detailed sampling or holding circuits, per se.
Subclass:
34
Narrow pulse elimination or suppression:
This subclass is indented under subclass 31. Subject matter
wherein the output signal does not include portions of the
input signal having a pulse width shorter than a
predetermined time interval.
(1) Note. Narrow or short pulse (spurious) duration in a
system may be noise, which is unwanted disturbances
superimposed upon a useful signal and which tends to obscure
its information content.
SEE OR SEARCH THIS CLASS, SUBCLASS:
172 for rectangular or pulse waveform continuous width
control.
178 for rectangular or pulse waveform amplitude control
which may include some noise reduction.
310 for transient or signal noise reduction by limiting,
clipping, or clamping.
379 for noise overriding in gating or switching.
551 for miscellaneous unwanted signal elimination.
Subclass:
35
Separating by duration or gap (e.g., duty cycle, etc.):
This subclass is indented under subclass 31. Subject matter
wherein (a) an input pulse signal is divided between long and
short pulses contained therein or (b) a space is inserted
between the trailing edge of a pulse and the leading edge of
the next pulse or (c) a spacing between pulses is detected.
SEE OR SEARCH THIS CLASS, SUBCLASS:
134 for duration control of a triangular or sawtooth wave.
172 for rectangular wave or pulse width control.
SEE OR SEARCH CLASS:
329, Demodulators, subclass 312 for a pulse width
demodulator.
Subclass:
36
Selection of a particular pulse width:
This subclass is indented under subclass 31. Subject matter
wherein a predetermined pulse width is chosen from a series
of input pulse signals.
SEE OR SEARCH CLASS:
329, Demodulators, subclass 312 for a pulse width
demodulator.
Subclass:
37
Comparison by threshold or reference:
This subclass is indented under subclass 31. Subject matter
wherein the output signal is indicative of the pulse width
difference between an input pulse signal and a set value or
predetermined standard.
Subclass:
38
With plural paths:
This subclass is indented under subclass 31. Subject matter
wherein an input signal passes through more than one route or
channel between an input terminal and an output terminal.
Subclass:
39
By frequency:
This subclass is indented under subclass 1. Subject matter
wherein the discriminated signal parameter relates to the
number of times a signal repeats its basic waveform within a
unit of time.
SEE OR SEARCH THIS CLASS, SUBCLASS:
2 for discriminating by phase.
47 for circuits where the output is present only at a
predetermined frequency of the input.
113 for miscellaneous frequency or repetition rate control.
114 for pulse generating which includes frequency or
repetition rate control.
231 for phase correction or control.
261 for output waveform production delay.
552 for unwanted signal suppression by an active filter.
SEE OR SEARCH CLASS:
303, Fluid-Pressure and Analogous Brake System, 91 for
speed-controlled fluid-pressure brake systems.
324, Electricity: Measuring and Testing, 76.19 for a
frequency spectrum analyzer and subclasses 76.39+ for
measuring and testing of the frequency of cyclic current or
voltage.
329, Demodulators, 315 for frequency demodulation in which
an intelligence signal is extracted.
331, Oscillators, 1 for systems for stabilizing the
frequency of an oscillator utilizing phase or frequency
comparison devices and subclasses 37+ for systems wherein two
or more frequencies are combined to produce a beat
frequency.
332, Modulators, 117 for systems wherein the frequency of a
carrier wave is modulated by an arbitrarily varying
quantity.
455, Telecommunications, subclass 214 for frequency or phase
modulation with particular discrimination or detection.
702, Data Processing: Measuring, Calibrating, or Testing, 75
for frequency measurement system.
Subclass:
40
Comparison between plural inputs:
This subclass is indented under subclass 39. Subject matter
wherein the output signal is a function of the differences
among two or more input signal frequencies.
(1) Note. Systems wherein the claimed subject matter
includes apparatus which responds only when a noninformation
bearing input signal is in synchronism with a control signal
locally generated (synchronous detectors) and which are not
claimed as an integral part of a more comprehensive system
will be classified herein. Detectors producing an output
which is a result of demodulation of a carrier having
previously been modulated by an intelligence waveform which
varies arbitrarily will not be classified here. See SEARCH
CLASS, below.
SEE OR SEARCH THIS CLASS, SUBCLASS:
3 for phase comparison between plural input signals.
SEE OR SEARCH CLASS:
329, Demodulators, appropriate subclasses for a circuit
having an output which is a result of demodulation of a
carrier having previously been frequency modulated by an
intelligence waveform.
455, Telecommunications, 130, for mixers or converters
utilized in a superheterodyne receiver (commonly referred to
as a first detector), and subclasses 313+ for combining
frequencies in a receiver to produce a beat frequency.
Subclass:
41
With synchronous detection:
This subclass is indented under subclass 40. Subject matter
wherein the output signal provides an indication of the
maintenance of precise matching between two or more input
signal frequencies.
SEE OR SEARCH THIS CLASS, SUBCLASS:
141 for synchronizing control.
SEE OR SEARCH CLASS:
331, Oscillators, 1 for controlling frequency
synchronization in oscillator circuits (e.g., phase lock loop
circuits, etc.).
348, Television, 638 and 726+ for television receivers that
may include synchronous detectors.
Subclass:
42
Fixed frequency reference signal:
This subclass is indented under subclass 40. Subject matter
wherein a signal of constant frequency acts as a standard for
comparison to a variable input signal.
SEE OR SEARCH THIS CLASS, SUBCLASS:
7 for a fixed phase signal compared to a variable input.
Subclass:
43
With logic or bistable circuit:
This subclass is indented under subclass 40. Subject matter
wherein the frequency comparison of plural signals (a)
includes a device performing Boolean functions such as AND,
OR, or exclusive-OR or (b) utilizes a device having two
stable states.
(1) Note. The combination of logic with specific frequency
comparison circuitry or function, not elsewhere classified is
classified here.
SEE OR SEARCH THIS CLASS, SUBCLASS:
185 for particular stable state circuits including
bistable.
SEE OR SEARCH CLASS:
326, Electronic Digital Logic Circuitry, 93 for clocking or
synchronizing of one or more logic stages and appropriate
subclasses for general digital logic circuitry not classified
elsewhere.
331, Oscillators, subclass 1 for automatic frequency control
synchronization with logic elements.
Subclass:
44
With predetermined frequency selection:
This subclass is indented under subclass 39. Subject matter
wherein the output signal consists of a chosen input signal
having a specific frequency characteristic.
SEE OR SEARCH THIS CLASS, SUBCLASS:
552 for unwanted signal suppression by an active filter.
SEE OR SEARCH CLASS:
329, Demodulators, appropriate subclasses for circuits which
select signals from modulated wave signals.
Subclass:
45
Including sampling or reference frequency:
This subclass is indented under subclass 44. Subject matter
wherein (a) the predetermined signal frequency selected is
derived by representation of another known signal frequency
at intermittent time intervals or (b) wherein a signal of
fixed frequency is utilized in the frequency selection.
SEE OR SEARCH THIS CLASS, SUBCLASS:
7 for phase angle sensing circuits using a reference
signal.
42 for a fixed frequency reference signal used in plural
signal frequency comparison.
Subclass:
46
Including plural frequency detection:
This subclass is indented under subclass 44. Subject matter
wherein more than one signal frequency is detected by a
single circuit or system.
Subclass:
47
Frequency detection:
This subclass is indented under subclass 39. Subject matter
wherein an output signal is present or changes only at a
predetermined input frequency.
SEE OR SEARCH THIS CLASS, SUBCLASS:
102 for the conversion of input frequency to output current
or voltage.
113 for frequency or repetition rate control.
552 for unwanted signal elimination by an active filter.
SEE OR SEARCH CLASS:
379, Telephonic Communications, subclass 346 for a repeater
with voice frequency discriminator.
708, Electrical Computers: Arithmetic Processing and
Calculating, 311 for frequency detection/filtering using an
electrical digital calculating computer.
Subclass:
48
With counting:
This subclass is indented under subclass 47. Subject matter
wherein the output signal is incremented or decremented at a
predetermined interval thereby forming a variable duty cycle
according to the changes in the input frequency signal.
(1) Note. A counter is a device capable of changing between
a sequence of distinguishable states upon each receipt of an
input signal.
SEE OR SEARCH CLASS:
377, Electrical Pulse Counters, Pulse Dividers, or Shift
Registers: Circuits and Systems, for counters, per se.
Subclass:
49
With logic or bistable circuit:
This subclass is indented under subclass 47. Subject matter
wherein the frequency detection (a) includes a device
performing Boolean functions such as AND, OR, or exclusive-OR
or (b) utilizes a device having two stable states.
(1) Note. The combination of logic with specific frequency
detection circuitry or function, not elsewhere classified, is
classified here.
SEE OR SEARCH THIS CLASS, SUBCLASS:
185 for particular stable state circuits including
bistable.
SEE OR SEARCH CLASS:
326, Electronic Digital Logic Circuitry, 93 for clocking or
synchronizing of one or more logic stages and appropriate
subclasses for general digital logic circuitry not classified
elsewhere.
Subclass:
50
By amplitude:
This subclass is indented under subclass 1. Subject matter
wherein the discriminated input signal parameter is the
magnitude of an electrical energy waveform measured with
respect to a fixed origin.
SEE OR SEARCH THIS CLASS, SUBCLASS:
178 for rectangular or pulse waveform amplitude control.
306 for amplitude control in general.
SEE OR SEARCH CLASS:
324, Electricity: Measuring and Testing, 76 for the
measuring or testing of electricity, per se.
329, Demodulators, 347 for amplitude demodulators.
Subclass:
51
With sensing amplifier:
This subclass is indented under subclass 50. Subject matter
wherein low-level voltages (e.g., CCD charges, capacitive
stored signal levels, etc.) are detected and increased in
magnitude from one level to another.
(1) Note. The voltage amplitude or storage charge levels
detected in this subclass include the type of levels found in
storage memory cells of an array; however, the static storage
and retrieval of information coupled with the functions of
"write", "read-out", "erase", etc., wherein voltage amplitude
is sensed, is classified elsewhere. See the Search Note
below.
(2) Note. Differential comparator type sensing amplifiers
including regenerative sensing arrangements (e.g., bistable
flip-flops) are classified in this subclass.
SEE OR SEARCH THIS CLASS, SUBCLASS:
28 for discrimination by polarity.
SEE OR SEARCH CLASS:
365, Static Information Storage and Retrieval, 189.01 for
networks including the inserting, extracting, or handling of
information signals using the functions of "write",
"read-out", "erase", etc., subclasses 185.01+ for floating
gate memory storage (e.g., flash memory); subclasses 189.01+
for the static storage and retrieval of information coupled
with the functions of "write", "read-out", "erase", etc.,
wherein voltage amplitude is sensed.
Subclass:
52
Differential amplifier:
This subclass is indented under subclass 51. Subject matter
including a device responsive to the offset between two input
voltages or currents and nonresponsive to voltages or
currents which are identical in the two inputs.
Subclass:
53
Current mirror:
This subclass is indented under subclass 52. Subject matter
wherein the sensing amplifier circuit utilizes collector
current matching of two transistors when connected base to
base and emitter to emitter.
Subclass:
54
Having feedback:
This subclass is indented under subclass 52. Subject matter
wherein a portion of the output signal is returned to an
input.
SEE OR SEARCH THIS CLASS, SUBCLASS:
57 for a miscellaneous sense amplifier with a latching type
element.
Subclass:
55
Cross-coupled:
This subclass is indented under subclass 54. Subject matter
wherein there are two elements or stages which are mutually
interconnected (i.e., the output of one is connected to the
input of the other and vice versa).
Subclass:
56
With reference signal:
This subclass is indented under subclass 52. Subject matter
wherein a signal of fixed voltage potential acts as a
constant for comparison to a variable input.
(1) Note. The reference signal is usually an input signal
or produced from an input signal.
SEE OR SEARCH THIS CLASS, SUBCLASS:
77 for amplitude comparison between an input signal and a
fixed reference, in general.
Subclass:
57
With latching type element (e.g., flip-flop, etc.):
This subclass is indented under subclass 51. Subject matter
wherein the sense amplifier includes a device providing
signal retention.
SEE OR SEARCH THIS CLASS, SUBCLASS:
185 for stable state circuits including bistable.
Subclass:
58
Maximum or minimum amplitude:
This subclass is indented under subclass 50. Subject matter
wherein an output signal is caused by either a greatest
absolute magnitude or a least absolute magnitude of an input
signal during a time period of interest.
(1) Note. This subclass does not include comparison to a
fixed reference or threshold.
Subclass:
59
Employing input compared to output:
This subclass is indented under subclass 58. Subject matter
wherein a portion of an output signal is evaluated relative
to an input signal.
Subclass:
60
Employing input compared to reference derived therefrom:
This subclass is indented under subclass 58. Subject matter
wherein a signal from an external source is evaluated
relative to a voltage or current obtained by processing
signals from the same source.
(1) Note. For this subclass either the processing or means
therefor should be claimed.
SEE OR SEARCH THIS CLASS, SUBCLASS:
72 for generic amplitude comparing between an input and a
reference derived therefrom.
Subclass:
61
By diode-capacitor network:
This subclass is indented under subclass 58. Subject matter
wherein maximum or minimum amplitude discriminating is
achieved by an electrical energy storage element combined
with an element providing unidirectional current flow.
Subclass:
62
Maximum and minimum amplitude:
This subclass is indented under subclass 58. Subject matter
wherein an output signal is caused by both the greatest
absolute magnitude and least absolute magnitude of an input
signal during a time period of interest.
Subclass:
63
Comparison between plural varying inputs:
This subclass is indented under subclass 50. Subject matter
wherein fluctuating input signals from two or more sources
external to a system are evaluated relative to one another.
SEE OR SEARCH THIS CLASS, SUBCLASS:
72 for evaluation of an input signal relative to a reference
derived therefrom.
74 for a system wherein a signal from an external source is
evaluated relative to plural fixed reference levels.
77 for the evaluation of a signal relative to a single fixed
reference level.
78 for detection of a crossover point between an input
signal and a reference level.
Subclass:
64
With logic or bistable circuit:
This subclass is indented under subclass 63. Subject matter
wherein the comparison by amplitude (a) includes a device
performing Boolean functions such as AND, OR, or exclusive-OR
or (b) utilizes a device having two stable states.
(1) Note. The combination of logic with specific amplitude
comparison circuitry or function, not elsewhere classified is
classified here.
SEE OR SEARCH THIS CLASS, SUBCLASS:
185 for particular stable state circuits including
bistable.
SEE OR SEARCH CLASS:
326, Electronic Digital Logic Circuitry, 93 for clocking or
synchronizing of one or more logic stages and appropriate
subclasses for general digital logic circuitry not classified
elsewhere.
Subclass:
65
Differential input:
This subclass is indented under subclass 63. Subject matter
wherein the differences between the plural varying input
signals are initially amplified prior to further processing.
Subclass:
66
Current mirror:
This subclass is indented under subclass 65. Subject matter
wherein the comparison between plural varying inputs utilizes
collector current matching of two transistors when connected
base to base and emitter to emitter.
Subclass:
67
Having feedback:
This subclass is indented under subclass 65. Subject matter
wherein a portion of the output signal is returned to an
input.
Subclass:
68
Input provides varying reference signal:
This subclass is indented under subclass 63. Subject matter
wherein at least one of the fluctuating inputs provides a
changing signal to be used only as an evaluation standard.
SEE OR SEARCH THIS CLASS, SUBCLASS:
72 for amplitude discriminating where a reference signal is
internally derived from one of the inputs.
Subclass:
69
With plural paths:
This subclass is indented under subclass 63. Subject matter
wherein an input signal passes through more than one route or
channel between an input terminal and an output terminal.
Subclass:
70
With single output:
This subclass is indented under subclass 69. Subject matter
wherein the plural paths have a common output.
SEE OR SEARCH THIS CLASS, SUBCLASS:
407 for plural channel input, single channel output gating
systems.
SEE OR SEARCH CLASS:
370, Multiplex Communications, appropriate subclasses for
similar subject matter used with multiplexing.
Subclass:
71
Three or more inputs:
This subclass is indented under subclass 63. Subject matter
wherein the number of external signal sources is greater than
two.
Subclass:
72
Input signal compared to reference derived therefrom:
This subclass is indented under subclass 50. Subject matter
wherein a signal from an external source is evaluated
relative to a voltage or current obtained by processing
signals from the same source.
(1) Note. For classification herein, either the processing
or means therefor should be recited.
SEE OR SEARCH THIS CLASS, SUBCLASS:
68 for amplitude discriminating between plural varying
inputs where at least one of the input signals is a varying
reference.
74 for an input signal compared to plural fixed references.
205 for stable state circuits utilizing hysteresis.
SEE OR SEARCH CLASS:
326, Electronic Digital Logic Circuits, 22 for input noise
margin enhancement.
Subclass:
73
Reference derived by feedback:
This subclass is indented under subclass 72. Subject matter
wherein the processing includes extracting a signal from an
output terminal of the circuit and applying a portion of the
extracted signal to an input terminal.
Subclass:
74
Input signal compared to plural fixed references:
This subclass is indented under subclass 50. Subject matter
wherein input signal amplitude is evaluated relative to two
or more unvarying voltage or current levels.
SEE OR SEARCH THIS CLASS, SUBCLASS:
63 for amplitude comparison between plural varying inputs.
72 for an input signal compared to a reference derived
therefrom.
77 for an input signal compared to a single fixed
reference.
205 for a stable state circuit utilizing hysteresis.
SEE OR SEARCH CLASS:
326, Electronic Digital Logic Circuits, subclass 22 for
input noise margin enhancement.
Subclass:
75
Three or more:
This subclass is indented under subclass 74. Subject matter
wherein there are more than two unvarying reference levels.
Subclass:
76
With logic or bistable circuit:
This subclass is indented under subclass 74. Subject matter
wherein the comparison by amplitude between the input signal
and plural fixed references (a) includes a device performing
Boolean functions such as AND, OR, or exclusive-OR or (b)
utilizes a device having two stable states.
SEE OR SEARCH THIS CLASS, SUBCLASS:
185 for particular stable state circuits including
bistable.
SEE OR SEARCH CLASS:
326, Electronic Digital Logic Circuitry, for general digital
logic circuitry not classified elsewhere and particularly 93
for clocking or synchronizing of one or more logic stages.
Subclass:
77
Input signal compared to single fixed reference:
This subclass is indented under subclass 50. Subject matter
wherein the input signal is evaluated relative to a standard
which is at a constant level of amplitude.
SEE OR SEARCH THIS CLASS, SUBCLASS:
74 for an input signal compared to multiple fixed
references.
Subclass:
78
Reference level crossover detecting:
This subclass is indented under subclass 77. Subject matter
wherein an output signal is produced when an input signal
actually transits the reference amplitude of a comparison
standard.
(1) Note. The approach of the input signal to the reference
level may be from either a positive or a negative direction.
SEE OR SEARCH THIS CLASS, SUBCLASS:
63 for evaluation of plural sources of varying input signals
relative to each other.
74 for evaluation of an input signal relative to plural
fixed thresholds.
Subclass:
79
Zero crossover:
This subclass is indented under subclass 78. Subject matter
wherein the reference level which is transited is zero
volts.
SEE OR SEARCH THIS CLASS, SUBCLASS:
451 for AC supply zero point switching utilizing a four or
more layer device such as a thyristor.
Subclass:
80
Reference determined by threshold of single circuit element:
This subclass is indented under subclass 77. Subject matter
wherein the amplitude of the comparison standard is
established by one electrical component.
Subclass:
81
With transistor:
This subclass is indented under subclass 80. Subject matter
wherein the single electrical component is a three terminal
semiconductor device composed of n or p type material.
SEE OR SEARCH CLASS:
257, Active Solid-State Devices (e.g., Transistors,
Solid-State Diodes), appropriate subclasses for transistor
structure details.
Subclass:
82
Plural sources of input signal:
This subclass is indented under subclass 77. Subject matter
wherein multiple input signals are to be evaluated relative
to a standard.
SEE OR SEARCH THIS CLASS, SUBCLASS:
63 for an amplitude evaluation system having plural varying
input signals which are to be evaluated against each other.
72 for a comparator system which evaluates an input signal
against a reference derived from the same signal.
Subclass:
83
Temperature compensation:
This subclass is indented under subclass 77. Subject matter
wherein an increase or decrease in thermal sensitivity of a
system is cancelled or reduced by the effects of a
counterbalancing element in the system.
(1) Note. A counterbalancing element may be, for example, a
resistor, capacitor, or inductor.
SEE OR SEARCH THIS CLASS, SUBCLASS:
513 for miscellaneous temperature compensation.
Subclass:
84
With bridge circuit:
This subclass is indented under subclass 77. Subject matter
including four or more devices with their input and output
terminals connected in a closed loop to form a four arm
network.
(1) Note. Another arm, called the diagonal arm, may be
connected between an input terminal and an output terminal.
SEE OR SEARCH THIS CLASS, SUBCLASS:
587 for a two electrode solid-state device bridge circuit.
588 for miscellaneous bridge circuits.
Subclass:
85
Inverting input or output:
This subclass is indented under subclass 77. Subject matter
wherein an input signal or an output signal is reversed in
sign.
Subclass:
86
With transformer:
This subclass is indented under subclass 77. Subject matter
wherein an electromagnetic induction device transfers
electrical energy between adjacent circuit portions at a
constant frequency.
(1) Note. A transformer changes voltage in direct
proportion to the ratio of the number of turns of its primary
and secondary windings.
SEE OR SEARCH CLASS:
336, Inductor Devices, appropriate subclasses for transformer
details.
Subclass:
87
Having feedback:
This subclass is indented under subclass 77. Subject matter
wherein a portion of the output signal is returned to an
input.
Subclass:
88
With source as reference:
This subclass is indented under subclass 77. Subject matter
wherein a device which supplies signal power at a constant
voltage or current level is used as a standard for
comparison.
SEE OR SEARCH THIS CLASS, SUBCLASS:
100 for signal generating.
540 for stabilized bias circuits with voltage regulating.
Subclass:
89
With differential amplifier:
This subclass is indented under subclass 77. Subject matter
including a device responsive to the offset between two input
voltages or currents and nonresponsive to voltages or
currents which are identical in the two inputs.
Subclass:
90
Comparison between two characteristics of an input signal:
This subclass is indented under subclass 50. Subject matter
wherein the output signal is representative of the amplitude
difference between two consecutive or selected points of the
input signal.
SEE OR SEARCH THIS CLASS, SUBCLASS:
91 for details of a sample or hold circuit.
Subclass:
91
Including details of sampling or holding:
This subclass is indented under subclass 50. Subject matter
wherein a representation of an input signal magnitude at a
particular point in time is produced or an established input
signal magnitude value is maintained.
SEE OR SEARCH THIS CLASS, SUBCLASS:
124 for signal generation by periodic switching.
365 for gating of signals, in general.
Subclass:
92
With bridge circuit:
This subclass is indented under subclass 91. Subject matter
including four or more devices with their input and output
terminals connected in a closed loop to form a four arm
network.
(1) Note. Another arm, called the diagonal arm, may connect
an input terminal and an output terminal.
SEE OR SEARCH THIS CLASS, SUBCLASS:
587 for a two electrode solid-state device bridge circuit.
588 for miscellaneous bridge circuits.
Subclass:
93
With reference source:
This subclass is indented under subclass 91. Subject matter
including a device which supplies signal power to a sample or
hold circuit at a constant voltage or current level.
SEE OR SEARCH THIS CLASS, SUBCLASS:
100 for signal converting, shaping, or generating.
530 for miscellaneous bias voltage supply circuits and
particularly subclasses 538+ for a stabilized bias voltage
supply circuit.
Subclass:
94
Sample and hold:
This subclass is indented under subclass 91. Subject matter
wherein a representation of an input signal magnitude at a
particular point in time is produced and subsequently
maintained for a time in a storage element.
SEE OR SEARCH CLASS:
341, Coded Data Generation or Conversion, 122 for sample and
hold circuits having code generation or conversion.
Subclass:
95
Having feedback:
This subclass is indented under subclass 94. Subject matter
wherein a portion of the output signal is returned to an
input.
Subclass:
96
With differential amplifier:
This subclass is indented under subclass 94. Subject matter
including a device responsive to the offset between two input
voltages or currents and nonresponsive to voltages or
currents which are identical in the two inputs.
Subclass:
97
With logic or bistable circuit:
This subclass is indented under subclass 50. Subject matter
wherein the comparison by amplitude (a) includes a device
performing Boolean functions such as AND, OR, or
exclusive-OR, or (b) utilizes a device having two stable
states.
(1) Note. The combination of logic with specific amplitude
comparison circuitry or function, not elsewhere classified is
classified here.
SEE OR SEARCH THIS CLASS, SUBCLASS:
185 for particular stable state circuits including
bistable.
SEE OR SEARCH CLASS:
326, Electronic Digital Logic Circuitry, 93 for clocking or
synchronizing of one or more logic stages and appropriate
subclasses for general digital logic circuitry not classified
elsewhere.
Subclass:
98
By separating composite signal:
This subclass is indented under subclass 1. Subject matter
wherein the output signal is a selected component of a
multicomponent input signal.
SEE OR SEARCH THIS CLASS, SUBCLASS:
35 for pulse separating by width or spacing.
551 for miscellaneous signal suppression which may include
an active filter.
SEE OR SEARCH CLASS:
307, Electrical Transmission or Interconnection Systems,
subclass 105 for harmonic filters or neutralizing systems,
in general.
324, Electricity: Measuring and Testing, 332 for
geophysical exploration systems utilizing radiant energy with
separate detector means whereby signal components are
selected or suppressed and subclasses 76.12+ for measuring
systems which analyze complex electric waves.
330, Amplifiers, appropriate subclasses for frequency
selective linear amplifiers.
331, Oscillators, subclass 76 and 77 for oscillator systems
combined with harmonic selecting means or wave filter,
respectively, in the output circuit.
333, Wave Transmission Lines and Networks, appropriate
subclasses for passive type wave selecting systems,
particularly 167 for wave filters, per se.
340, Communications: Electrical, 825.71 for selective
systems which are frequency responsive.
348, Television, subclass 506 for burst separation
circuitry, subclasses 525+ for separating the synchronizing
components from a composite signal wave, and subclasses 638+
for color signal deriving circuitry.
704, Data Processing: Speech Signal Processing, Linguistics,
Language Translation, and Audio Compression/Decompression,
subclass 200 for systems for analyzing complex speech waves
(e.g., where the fundamental pitch frequency of the human
voice is determined).
Subclass:
99
Having selection between plural continuous waveforms:
This subclass is indented under subclass 1. Systems wherein
the output signal is one of a plurality of simultaneously
applied input signal waveforms selected in accordance with a
predetermined characteristic, the nonselected waveforms being
attenuated or otherwise suppressed in such a manner that only
the desired signal waveform appears at the output.
SEE OR SEARCH THIS CLASS, SUBCLASS:
98 for systems which select a signal component from a
composite wave.
407 for distribution systems wherein plural channels are
input and the output consists of a signal from a selected
channel.
SEE OR SEARCH CLASS:
324, Electricity: Measuring and Testing, 76.12 for analysis
systems of a complex wave.
331, Oscillators, subclass 76 for systems comprising an
oscillator combined with a harmonic selection network and
subclass 77 for oscillators with a wave selecting output
filter.
333, Wave Transmission Lines and Networks, 167 for wave
filters comprised of passive elements.
340, Communications: Electrical, 825.71 for remote control
or selective signaling systems which are frequency
responsive.
348, Television, 525 for separating the synchronizing
components from a composite signal wave.
Subclass:
100
SIGNAL CONVERTING, SHAPING, OR GENERATING:
This subclass is indented under the class definition.
Subject matter wherein (a) an inherent input signal parameter
such as phase, frequency, amplitude, or current is modified,
maintained at some value, or changed to an entirely different
parameter, (b) an input signal having a particular waveform
is modified into an output signal having a partially or
completely different waveform, or (c) an output signal of
specified waveform is produced.
(1) Note. An example of the second type above would be sine
wave to triangular wave modification.
(2) Note. This subclass and indented subclasses do not
include single energy systems for conversion wherein a single
electrical source circuit is coupled to a single electrical
load circuit and which involves current, phase or frequency
conversion, and wherein the energy in the load is supplied
solely by the source. Such systems in general are classified
in Class 363, Electric Power Conversion Systems, appropriate
subclasses. See References to Other Classes in Class 363 for
other classes providing for conversion systems.
(3) Note. Excluded from this subclass and indented
subclasses are free running signal generators which are
classified, for example, in Class 331.
(4) Note. Bias circuits of the pulsing type which establish
device operating points are classified below with the bias
circuits.
SEE OR SEARCH THIS CLASS, SUBCLASS:
334 for circuits whose output is proportional to a
mathematical function of the input.
544 for bias circuits of the pulsating type.
596 for miscellaneous circuits including a free running
oscillatory type circuit.
SEE OR SEARCH CLASS:
128, Surgery, subclass 2.06 for electrocardiographs
involving timing and subclasses 303.13+ for instruments for
application of electricity to the human body involving
timing.
236, Automatic Temperature and Humidity Regulation, subclass
46 for regulation systems involving timing.
237, Heating Systems, 2 for systems for automatic control of
a heating system.
307, Electrical Transmission or Interconnection Systems, 401
for nonlinear reactor systems (e.g., saturable) and
subclasses 106+ for a class appropriate wave shape
determinative or pulse producing system. See also
appropriate subclasses for plural source or load voltage
magnitude and phase control.
315, Electric Lamp and Discharge Devices: Systems, 364 for
cathode ray deflecting circuits involving timing and
subclasses 209+ for systems involving a periodic switch in
the supply circuit of a gaseous discharge tube.
318, Electricity: Motive Power Systems, subclass 445 for
systems of automatically starting and/or stopping a motor
with timing, subclasses 606+ for electric motor position
servomechanisms with phase or frequency control, and subclass
683 for particular phase detectors used in such a
servomechanism.
320, Electricity: Battery or Capacitor Charging or
Discharging, 166 for charging or discharging a capacitor,
per se.
322, Electricity: Single Generator Systems, 17, especially
indented subclass 18 for systems involving time delay means
in the control of a generator or driving.
323, Electricity: Power Supply or Regulation Systems, 212
for power supply phase control comprising an electron tube
and wherein, in general, the tube does not act as an active
element.
324, Electricity: Measuring and Testing, 83 for phase
indicators, subclasses 78+, particularly subclass 82 for
measuring or testing the frequency of cyclic current or
voltage by phase comparison, and subclasses 160+ for systems
for measuring time or speed.
330, Amplifiers, subclass 107 for amplifiers with phase
shifting means in a feedback path.
331, Oscillators, 37 for systems including an oscillator or
oscillators generating at least two different frequencies
with a signal combining device (e.g., mixer, modulator, etc.)
having a signal input circuit and a signal output circuit
where the oscillator or oscillators are connected to the
signal input circuit of the combining device and the device
output comprises the sum or difference frequency of the
outputs of the oscillator or oscillators.
332, Modulators, appropriate subclasses for systems including
beating a source of carrier frequency with a signal wave
which varies arbitrarily in a continuous manner in accordance
with some intelligence.
333, Wave Transmission Lines and Networks, subclass 18, 23,
and 138+ for delay networks comprising passive elements and
subclasses 138+. See (1) Note, above.
340, Communications: Electrical, subclass 870.24 for
telemetering systems receiving information by pulse trains
with length or spacing varied with respect to time.
341, Coded Data Generation or Conversion, 50 for systems
converting an input consisting of a coded arrangement
representing a particular group of values to an output
consisting of another coded arrangement.
348, Television, 469 for systems generating or formatting a
television signal.
361, Electricity: Electrical Systems and Devices, 195 for
time delay networks which control a relay load switching
operation.
363, Electric Power Conversion Systems, appropriate
subclasses for single energy conversion systems wherein a
single electrical source circuit is coupled to a single
electrical load circuit. See (2) Note, above.
455, Telecommunications, 313 for mixer or converters in
radio receiver circuits. See (3) Note, above.
Subclass:
101
Converting input current or voltage to output frequency:
This subclass is indented under subclass 100. Subject matter
wherein a repetition rate of an output signal is directly
related to the magnitude of an input signal current or
voltage.
SEE OR SEARCH THIS CLASS, SUBCLASS:
113 for miscellaneous frequency or repetition rate
conversion or control.
SEE OR SEARCH CLASS:
332, Modulators, 117 for a frequency modulator.
Subclass:
102
Converting input frequency to output current or voltage:
This subclass is indented under subclass 100. Subject matter
wherein the magnitude of output signal current or voltage is
directly related to the repetition rate of the input signal.
(1) Note. Included here are devices wherein an input signal
of varying frequency is changed into a direct current output
voltage which is a function of the input frequency.
(2) Note. Since period is inversely related to frequency,
input period conversion to output current or voltage is also
included here.
SEE OR SEARCH THIS CLASS, SUBCLASS:
39 for frequency discrimination and particularly subclasses
47+ for frequency detection.
SEE OR SEARCH CLASS:
329, Demodulators, 315 for a frequency demodulator.
Subclass:
103
Converting input voltage to output current or vice versa:
This subclass is indented under subclass 100. Subject matter
wherein electrical potential is changed to an equivalent
electrical charge flow or vice versa.
SEE OR SEARCH CLASS:
363, Electric Power Conversion Systems, subclass 73 for
power conversion systems between a constant current and a
constant voltage or vice versa wherein a single source is
connected to a single load.
Subclass:
104
Converting, per se, of an AC input to corresponding DC at an
unloaded output:
This subclass is indented under subclass 100. Subject matter
wherein an alternating current input signal wave is converted
to an unloaded output wave consisting of a unidirectional
representation of the half cycles of an input wave.
(1) Note. The conversion systems in this subclass do not
include claimed subject matter such as would define
demodulators, detectors, or rectifier systems classified
elsewhere with specific art devices.
SEE OR SEARCH THIS CLASS, SUBCLASS:
28 for polarity selection or discrimination.
39 for selection or discrimination by repetition rate (i.e.,
frequency).
335 for a differentiating network.
336 for an integrating network.
348 for the determination of the RMS function of an input
signal.
SEE OR SEARCH CLASS:
178, Telegraphy, appropriate subclasses for pulse producing
(e.g., by rectification of AC signals, etc.) in combination
with telegraph systems. In Class 178, the pulses are usually
representative of a telegraph code. 118 relate to telegraph
receivers which may include signal rectifiers.
246, Railway Switches and Signals, appropriate subclasses for
railway signaling systems which may include signal rectifying
or other conversion systems as subcombinations thereof.
307, Electrical Transmission or Interconnection Systems,
subclass 6 for systems having series connected converters of
different voltages, subclass 45 for plural supply circuits
with intervening converter, subclass 58 for load current
dividing circuits utilizing plural converters, subclass 82
for plural converter systems, subclasses 401+ for nonlinear
reactor systems, and subclass 107 for wave form or wave shape
determining systems with wave rectification.
320, Electricity: Battery or Capacitor Charging or
Discharging, appropriate subclass for charging or discharging
a capacitor or battery where a rectifier is employed,
particularly Digest 31.
324, Electricity: Measuring and Testing, subclass 89 for
phase comparison meters and subclass 119 for meters in
general with rectifying.
329, Demodulators, for demodulating systems using
rectification designed to change a signal modulated wave so
as to produce in the output circuit a pulsating direct
current representative of the signal.
330, Amplifiers, appropriate subclasses for amplifiers,
especially subclass 10 for modulator-demodulator type
amplifiers.
343, Communications: Radio Wave Antennas, appropriate
subclasses for signaling systems including radar and
directive radio systems which may include demodulating type
conversion systems as subcombinations thereof.
363, Electric Power Conversion Systems, 13 for rectification
and derectification involving a single source coupled to a
single load in a power conversion system. See the class
definition and search notes as to lines with other classes
and further fields of search for rectifying systems.
375, Pulse or Digital Communications, appropriate subclasses
and particularly 37 for pulse communication systems using
alternating or pulsating currents.
379, Telephonic Communications, appropriate subclasses for
pulse producing systems with signal rectifying or other
converting for use in telephone call transmitter systems.
Subclass:
105
Synthesizer:
This subclass is indented under subclass 100. Subject matter
wherein an output waveform is derived which at any instant is
proportional to the combined values of the corresponding
instantaneous values of a plurality of input signal
waveforms.
SEE OR SEARCH THIS CLASS, SUBCLASS:
3 for circuits where the output is a function of the phase
difference between plural input signal wave forms.
40 for circuits where the output is a function of the
frequency difference between plural input signal wave forms.
129 for miscellaneous sine wave generation.
355 for circuits where the output signal is a function of a
plurality of input signals.
361 for mathematical summing of two or more input signals.
SEE OR SEARCH CLASS:
84, Music, 600 for generation of electrical musical tones
utilizing synthesizing techniques.
324, Electricity: Measuring and Testing, subclass 77 for
systems for analyzing complex electric waves and subclass 140
for measuring and testing circuits which combine plural
inputs.
331, Oscillators, 37 for oscillatory circuits whose output
comprises a beat frequency and subclasses 46+ for plural
oscillator systems.
332, Modulators, appropriate subclasses for plural wave
modulating circuits.
333, Wave Transmission Lines and Networks, appropriate
subclasses, especially subclass 20 for passive wave shaping
networks.
455, Telecommunications, 313 for plural wave combining
heterodyning systems utilized in radio receivers wherein the
output is a beat frequency.
Subclass:
106
Having stored waveform data (e.g., in ROM, etc.):
This subclass is indented under subclass 105. Subject matter
wherein information about a desired output waveform is placed
into a memory device.
SEE OR SEARCH CLASS:
365, Static Information Storage and Retrieval, appropriate
subclasses for read-only memory (ROM) circuits in general.
Subclass:
107
Having digital device (e.g., logic gate, flip-flop, etc.):
This subclass is indented under subclass 105. Subject matter
wherein a device which operates on binary signals is
included.
SEE OR SEARCH THIS CLASS, SUBCLASS:
185 for miscellaneous flip-flop circuits.
SEE OR SEARCH CLASS:
326, Electronic Digital Logic Circuitry, appropriate
subclasses for logic gates, per se.
Subclass:
108
Current driver:
This subclass is indented under subclass 100. Subject matter
wherein an input signal is modified into a similar output
signal having an enhanced current supplying ability.
(1) Note. Current driving of the type associated with
electronic digital logic circuitry is classified in Class
326.
SEE OR SEARCH THIS CLASS, SUBCLASS:
139 for sawtooth signal waveform production without output
current drive enhancement and having an inductive load.
SEE OR SEARCH CLASS:
307, Electrical Transmission or Interconnection Systems, 401
and particularly subclass 412 for similar subject matter
where a nonlinear reactive element (e.g., magnetic core) is
claimed as forming part of the operative combination of the
invention.
326, Electronic Digital Logic Circuitry, 82 for logic
current driving.
365, Static Information Storage and Retrieval, appropriate
subclasses for magnetic storage of signals on magnetic
cores.
Subclass:
109
Having semiconductive load:
This subclass is indented under subclass 108. Subject matter
wherein the output drive current is provided to a broadly
recited semiconductive device.
SEE OR SEARCH CLASS:
257, Active Solid-State Devices (e.g., Transistors,
Solid-State Diodes), appropriate subclasses for detailed
semiconductor structure.
Subclass:
110
Having inductive load (e.g., coil, etc.):
This subclass is indented under subclass 108. Subject matter
wherein the output drive current is provided to a broadly
recited element which has the property of opposing current
flow therethrough due to a resultant magnetic field.
SEE OR SEARCH THIS CLASS, SUBCLASS:
139 for a circuit providing a sawtooth or triangular
waveform, as generated, to an inductive load.
190 for a stable state circuit utilizing a transformer or
saturable core device.
SEE OR SEARCH CLASS:
336, Inductor Devices, appropriate subclasses for generic
inductive devices.
Subclass:
111
Having capacitive load:
This subclass is indented under subclass 108. Subject matter
wherein the output drive current is provided to a broadly
recited element which has the property of opposing voltage
change due to stored charge.
SEE OR SEARCH CLASS:
361, Electricity: Electrical Systems and Devices, 500 for
electrolytic capacitors.
Subclass:
112
Push-pull:
This subclass is indented under subclass 111. Subject matter
wherein an output circuit comprises two parallel identical
portions each receiving signals which are the same except for
a relative 180 degree phase offset.
SEE OR SEARCH CLASS:
330, Amplifiers, 250 and particularly subclasses 262+ for
semiconductor push-pull amplifiers, in general.
Subclass:
113
Frequency or repetition rate conversion or control:
This subclass is indented under subclass 100. Subject matter
wherein a frequency characteristic of an input signal is
modified to produce an output wave of different frequency
characteristic which has a definite relationship to that of
the input wave or where a frequency characteristic is held
essentially constant.
SEE OR SEARCH THIS CLASS, SUBCLASS:
39 for frequency discrimination without subsequent control.
141 for miscellaneous synchronization circuits.
231 for circuits providing a phase shift less than the
period of an input signal.
SEE OR SEARCH CLASS:
84, Music, 600 for apparatus for generating or modifying
electric currents or potentials to produce varying electric
currents or potentials in combination with or intended for
use with structure for converting the varying electric
currents or potentials into musical tones.
250, Radiant Energy, subclass 250 for wave meters which may
employ frequency changing.
307, Electrical Transmission or Interconnection Systems, 424
for parametric amplifier frequency converters, per se.
324, Electricity: Measuring and Testing, 79 for electric
wave frequency measuring systems of the heterodyne type.
329, Demodulators, 323 or 346 for frequency or phase
demodulators with oscillators.
331, Oscillators, 37 for beat frequency oscillator systems
and subclass 76 for systems including an oscillator combined
with a harmonic producing or selecting network in the output.
To be classified in Class 331 the oscillator must be the
signal source and must be capable of self sustained
oscillation.
332, Modulators, 117 or 144+ for systems wherein a first
source is modified in frequency or phase by mixing with an
arbitrarily varying control source.
340, Communications: Electrical, particularly 870.01 for
telemetering systems and especially subclasses 870.18+
providing for frequency or phase modulation systems.
343, Communications: Radio Wave Antennas, appropriate
subclasses for systems involving object detection by
reflected pulses which may utilize phase or frequency
modulation.
363, Electric Power Conversion Systems, 157 for frequency
conversion systems wherein a single electrical source is
coupled to a single electrical load in a power conversion
system.
375, Pulse or Digital Communications, appropriate subclasses
for pulse communication systems which utilize phase or
frequency modulation.
377, Electrical Pulse Counters, Pulse Dividers, or Shift
Registers: Circuits and Systems, for pulse counters or
counting systems.
455, Telecommunications, 313 for radio receivers including
frequency changing means.
Subclass:
114
Of output rectangular waveform:
This subclass is indented under subclass 113. Subject matter
including maintaining constant or varying the repetition rate
of a continuous series of pulses having negligible transition
times and available at a specific circuit location for
subsequent utilization.
SEE OR SEARCH THIS CLASS, SUBCLASS:
39 for frequency sensitive systems and see also the search
notes thereunder.
SEE OR SEARCH CLASS:
84, Music, 600 for apparatus for generating or modifying
electric currents or potentials to produce varying electric
currents or potentials in combination with or intended for
use in converting the varying electric currents or potentials
into musical tones.
250, Radiant Energy, subclass 250 for wave meters which may
employ frequency changing.
307, Electrical Transmission or Interconnection Systems,
subclass 424 for parametric amplifier frequency converters.
324, Electricity: Measuring and Testing, subclass 79 for
electric wave frequency measuring systems of the heterodyne
type.
329, Demodulators, 323 for a frequency demodulator with a
local oscillator and subclass 346 for a phase demodulator
with a local oscillator.
331, Oscillators, 37 for beat frequency oscillator systems
and subclass 76 for systems including an oscillator combined
with a harmonic producing or selecting network in the output.
(To be classified in Class 331 the oscillator must be the
signal source and must be capable of self sustained
oscillation).
332, Modulators, appropriate subclasses for systems wherein a
first source of one frequency is modified in frequency or
phase by mixing with an arbitrarily varying control source of
another frequency or frequencies.
340, Communications: Electrical, appropriate subclasses for
systems whereby information is conveyed from one point to
another by pulses arranged in a particular sequence or whose
height or duration are varied to represent the particular
information to be conveyed, particularly 870.01 for
telemetering systems, and subclasses 870.18+ for such
systems providing frequency or phase modulation.
375, Pulse or Digital Communications, appropriate subclasses
for pulse communication systems which utilize phase or
frequency modulation.
377, Electrical Pulse Counters, Pulse Dividers, or Shift
Registers: Circuits and Systems, for pulse counters or
counting systems.
Subclass:
115
Frequency division:
This subclass is indented under subclass 114. Subject matter
wherein the repetition rate of the output pulses is less than
the frequency of the input signal.
SEE OR SEARCH THIS CLASS, SUBCLASS:
117 for frequency division, in general.
SEE OR SEARCH CLASS:
377, Electrical Pulse Counters, Pulse Dividers, or Shift
Registers: Circuits and Systems, appropriate subclasses for
analogous circuits which may utilize shift registers or other
class appropriate devices.
Subclass:
116
Frequency multiplication:
This subclass is indented under subclass 114. wherein the
repetition rate of the output pulses is greater than the
frequency of the input signal.
(1) Note. Miscellaneous frequency mixing which produces sum
or difference frequencies of two input frequencies is
classified in subclass 113. Rectangular or pulse waveform
frequency mixing is classified in subclass 114.
SEE OR SEARCH THIS CLASS, SUBCLASS:
119 for frequency multiplication in general.
SEE OR SEARCH CLASS:
377, Electrical Pulse Counters, Pulse Dividers, or Shift
Registers: Circuits and Systems, appropriate subclasses for
analogous circuits which may utilize shift registers or other
class appropriate devices.
Subclass:
117
Frequency division:
This subclass is indented under subclass 113. Subject matter
wherein an input signal having a first frequency is
transformed into an output signal having a second lower
frequency where the output frequency is a submultiple of the
input frequency.
(1) Note. Included as submultiples are fractions such as
two-thirds.
SEE OR SEARCH THIS CLASS, SUBCLASS:
114 for frequency conversion of a pulse train.
119 for miscellaneous frequency multiplication.
185 for particular multivibrator type which may or may not
be used as a frequency divider.
SEE OR SEARCH CLASS:
84, Music, 600 for apparatus for generating or modifying
electric currents or potentials to produce varying electric
currents or potentials in combination with or intended for
use with structure for converting the varying electric
currents or potentials into musical tones.
363, Electric Power Conversion Systems, 157 for frequency
conversion systems of a single electrical source coupled to a
single electrical load where there is no intermediate
conversion to DC.
Subclass:
118
Having discrete active device (e.g., transistor, triode,
etc.):
This subclass is indented under subclass 117. Subject matter
including an individual semiconductive or electron space
discharge device.
Subclass:
119
Frequency multiplication (e.g., harmonic generation, etc.):
This subclass is indented under subclass 113. Subject matter
wherein an input signal having a first frequency is
transformed into an output signal having a second higher
frequency, where the output frequency is a multiple of the
input frequency.
(1) Note. A harmonic output frequency is an integral
multiple of an input frequency.
(2) Note. Miscellaneous frequency mixing which produces sum
or difference frequencies of two input frequencies is
classified in subclass 113. Rectangular or pulse waveform
frequency mixing is classified in subclass 114.
SEE OR SEARCH THIS CLASS, SUBCLASS:
113 for miscellaneous frequency mixing.
114 for pulse frequency mixing.
116 for frequency multiplication of an output rectangular or
pulse waveform.
117 for miscellaneous frequency division.
SEE OR SEARCH CLASS:
84, Music, 600 for apparatus for generating or modifying
electric currents or potentials to produce varying electric
currents or potentials in combination with or intended for
use with structure for converting the varying electric
currents or potentials into musical tones.
307, Electrical Transmission or Interconnection Systems,
subclass 105 for a class appropriate harmonic filter or
neutralizer.
331, Oscillators, subclass 76 for oscillators combined with
electron space discharge tube harmonic generating or
selecting.
363, Electric Power Conversion Systems, 157 for frequency
conversion systems of a single electrical source coupled to a
single electrical load where there is no intermediate
conversion to DC.
Subclass:
120
With plural outputs:
This subclass is indented under subclass 119. Subject matter
wherein multiple harmonic output waves are simultaneously
derived from a single input wave.
(1) Note. The plurality of output waves are generally
derived from separate output terminals by filter or other
load.
Subclass:
121
Selective:
This subclass is indented under subclass 120. Subject matter
wherein one or more of the multiple output harmonic waves may
be chosen for utilization.
SEE OR SEARCH THIS CLASS, SUBCLASS:
407 for a switching circuit having plural inputs and a
single output.
Subclass:
122
Doubling:
This subclass is indented under subclass 119. Subject matter
wherein the frequency of the output wave is exactly twice the
frequency of the input wave independent of the input
frequency.
(1) Note. Included in this subclass are systems in which
the claimed subject matter is restricted to frequency
doublers even though the system singularly or in combination
with similar systems may be used as a frequency multiplier
other than a doubler.
Subclass:
123
With particular tube or distributed parameter element:
This subclass is indented under subclass 119. Subject matter
wherein a harmonic producing device comprises a particular
electron space discharge device or an element whose
respective impedance cannot be considered to be concentrated
at a point.
SEE OR SEARCH THIS CLASS, SUBCLASS:
593 for miscellaneous circuits with distributed parameter
elements.
SEE OR SEARCH CLASS:
331, Oscillators, subclass 76 for oscillators combined with
electron space discharge tube harmonic generating or
selecting.
Subclass:
124
By periodic switching (e.g., chopper, etc.):
This subclass is indented under subclass 100. Subject matter
wherein an input signal (typically low magnitude DC) is
regularly interrupted to form a pulsating output waveform.
SEE OR SEARCH THIS CLASS, SUBCLASS:
291 for miscellaneous clock or pulse generating.
365 for electronic input/output switching, in general.
548 for miscellaneous circuits providing a specific source
of supply or bias using an oscillator or interrupter.
SEE OR SEARCH CLASS:
307, Electrical Transmission or Interconnection Systems, 132
for relay repetitive make and break systems.
330, Amplifiers, subclass 10 for interrupters used in
modulator-demodulator type amplifiers.
363, Electric Power Conversion Systems, 106 and subclass 177
for circuit interrupter type converters for power systems.
370, Multiplex Communications, appropriate subclasses for
multiplex systems which utilize switching techniques.
Subclass:
125
Generating parabolic or hyperbolic output:
This subclass is indented under subclass 100. Subject matter
wherein a waveform is generated having the shape produced by
(a) a locus of points each of which has an equal distance to
a fixed line and a fixed point or (b) a locus of points
wherein the difference in distances from each point to two
fixed points is a constant.
SEE OR SEARCH CLASS:
708, Electrical Computers: Arithmetic Processing and
Calculating, subclass 853 for a hyperbolic function
generator using an analog computer.
Subclass:
126
Generating staircase output:
This subclass is indented under subclass 100. Subject matter
including the generation of a signal whose amplitude
increases or decreases between three or more discrete steps
at regular intervals.
SEE OR SEARCH THIS CLASS, SUBCLASS:
105 for wave synthesizing systems.
131 for sawtooth or triangular wave output.
291 for an output discretely stepping between two levels.
355 for systems wherein the output is a resultant function
of plural inputs.
SEE OR SEARCH CLASS:
315, Electric Lamp and Discharge Devices: Systems, 364 for
step wave deflection systems used with cathode-ray tubes.
370, Multiplex Communications, subclass 530 for a
multiplexing system using a time-division step wave signal.
Subclass:
127
With differential amplifier:
This subclass is indented under subclass 126. Subject matter
including a gain producing device responsive to the offset
between two input voltages or currents and nonresponsive to
voltages or currents which are identical in the two inputs.
SEE OR SEARCH THIS CLASS, SUBCLASS:
563 for a nonlinear amplifier circuit utilizing a
differential amplifier.
SEE OR SEARCH CLASS:
330, Amplifiers, 252 for a semiconductor differential
amplifier in general.
Subclass:
128
With rectifying element:
This subclass is indented under subclass 126. Subject matter
including an element converting an alternating current wave
into a corresponding direct current wave.
SEE OR SEARCH THIS CLASS, SUBCLASS:
104 for a converter of an AC input to corresponding DC at an
unloaded output.
SEE OR SEARCH CLASS:
363, Electric Power Conversion Systems, 13 for current
conversion (including rectification) in a power system which
connects a single electrical source to a single electrical
load.
Subclass:
129
Generating sinusoidal output:
This subclass is indented under subclass 100. Subject matter
wherein an input signal wave is modified to or triggers an
alternating current sinusoidal wave at the output.
(1) Note. Included here are signals having a cosinusoidal
waveform.
SEE OR SEARCH THIS CLASS, SUBCLASS:
32 for a shock excited tuned circuit utilized in pulse width
or spacing selection.
104 for miscellaneous converters of an AC signal input to DC
voltage output.
105 for synthesizing of an output waveform.
113 for systems providing frequency conversion.
306 for systems wherein the amplitude of an output wave is
controlled within specific limits.
596 for miscellaneous circuits including an oscillatory or
shock excited portion.
SEE OR SEARCH CLASS:
84, Music, 600 for various systems for modifying electric
currents or potentials in combination with converting the
varying electric currents or potentials into sound waves for
the production of musical tones.
128, Surgery, 419 for systems wherein the usual 60 Hz
commercial alternating current is converted to high frequency
AC or pulsating current for application to the human body.
178, Telegraphy, 66.1 for systems relating to frequency
shift keying of an alternating current signal under the
influence of a control pulse.
310, Electrical Generator or Motor Structure, subclass 160
for structural details of a rotary mechanical AC frequency
converter and subclass 161 for phase shifter type rotary AC
dynamoelectric machines.
315, Electric Lamp and Discharge Devices: Systems, 378 and
391+ for systems which deflect a cathode ray by a rotating
electric field having conversion of pulse wave energy to
alternating wave energy, subclasses 200+ for systems
comprising a discharge device or rectifier in the supply
circuit of a gaseous tube or tubes where the output may be an
alternating circuit wave, subclasses 209+ for systems
comprising a periodic switch in the supply circuit of a
gaseous tube or tubes where the switch may be pulse
controlled with the output an AC wave and subclasses 246+ for
systems comprising a pulsating supply for gaseous tubes.
318, Electricity: Motive Power Systems, subclass 138 for
systems wherein a motor is of the space discharge device
commutated type and wherein a pulsing current may be
converted to an equivalent alternating current.
331, Oscillators, particularly 37 for systems comprising the
combination of oscillator with production of a beat
frequency, subclass 45 for an oscillator with polyphase
output, and subclasses 172+ for an oscillator combined with
pulse actuated control or synchronization.
332, Modulators, 117 or 144+ for devices for modulating the
phase or frequency of a carrier wave by an arbitrarily
varying control wave.
333, Wave Transmission Lines and Networks, subclass 20 for
systems comprising wave shape changing utilizing passive
elements.
340, Communications: Electrical, appropriate subclasses for
signaling or indicating devices responsive to pulse wave
input and in which the output may or may not be an
alternating current.
343, Communications: Radio Wave Antennas, appropriate
subclasses for receivers for pulse wave transmitted carrier
wave energy.
363, Electric Power Conversion Systems, 13 for systems
involving derectification, subclasses 148+ for systems
including phase conversion, and subclass 157 for systems
including frequency conversion wherein a single source is
connected to a single load.
375, Pulse or Digital Communications, subclasses 1-58 for
pulse responsive systems, subclasses 62+ for systems for
transmitting information including frequency shift keying,
and subclasses 75+ for pulse responsive receivers.
455, Telecommunications, 313 for systems whereby an input
modulated carrier wave is modified by a wave derived from a
local oscillator or other source in such a manner as to
obtain an output wave the frequency of which is the sum or
difference of the input wave and the modifying wave (i.e., a
beat frequency).
Subclass:
130
Generating trapezoidal output:
This subclass is indented under subclass 100. wherein the
output waveform comprises an initial sloped rise from a
normal voltage level followed by a steady level which is
followed by a sloped return to the normal voltage level and
where the sloped portions are mirror images.
SEE OR SEARCH THIS CLASS, SUBCLASS:
131 for miscellaneous circuits producing a sawtooth or
triangular output.
Subclass:
131
Generating sawtooth or triangular output:
This subclass is indented under subclass 100. Subject matter
wherein a waveform is generated having a positive slope
followed immediately by a negative slope.
(1) Note. The positive slope is generally gradual (e.g., by
slowly charging a capacitor, etc.), and the negative slope is
generally much more rapid (e.g., by quickly discharging a
capacitor).
(2) Note. The slopes of a sawtooth waveform produced may
only approximate a straight line.
SEE OR SEARCH THIS CLASS, SUBCLASS:
126 for staircase output generation which may approximate a
ramp or sawtooth signal.
335 for differentiating networks.
336 for integrating networks.
SEE OR SEARCH CLASS:
315, Electric Lamp and Discharge Device: Systems, 364 for
cathode-ray tube beam deflecting systems.
331, Oscillators, 20, 111+, 129+, and 143+ for free running
sawtooth wave generators.
348, Television, particularly 536 for television systems
which may include sawtooth generating circuits.
Subclass:
132
With current source or current mirror:
This subclass is indented under subclass 131. Subject matter
including a circuit portion which supplies a particular level
of electrical current therethrough or a circuit portion
having collector current matching in a pair of transistors
having their bases and emitters tied together.
SEE OR SEARCH THIS CLASS, SUBCLASS:
133 for linearization in a sawtooth or triangular wave
generator.
540 for current source regulating in a stabilized bias
circuit.
SEE OR SEARCH CLASS:
323, Electricity: Power Supply or Regulation Systems, for
generic current regulation.
Subclass:
133
With distortion control (e.g., linearization, etc.):
This subclass is indented under subclass 131. Subject matter
which compensates for or introduces output waveform
irregularities.
(1) Note. Distortion is sometimes introduced to the
sawtooth or triangular signal to balance out some anticipated
subsequent circuit distortion.
SEE OR SEARCH THIS CLASS, SUBCLASS:
132 for systems wherein the linearization includes a
constant current device.
165 for regenerating or restoring a rectangular waveform.
317 for an amplitude controlled distortion compensation
circuit.
379 for signal transmission integrity in a circuit providing
gating of an unmodified input signal to an output.
551 for miscellaneous unwanted signal suppression.
Subclass:
134
With slope or duration control:
This subclass is indented under subclass 131. Subject matter
wherein the inclination or the period of the generated output
is regulated.
SEE OR SEARCH THIS CLASS, SUBCLASS:
13 for systems for selecting pulses as a function of slope
or shape.
130 for a circuit generating a trapezoidal output.
170 for slope control of a leading or trailing edge of a
rectangular waveform.
Subclass:
135
Having digital element:
This subclass is indented under subclass 131. Subject matter
including a device performing a logical function.
(1) Note. An example of a digital element is an AND gate.
SEE OR SEARCH CLASS:
326, Electronic Digital Logic Circuitry, appropriate
subclasses for digital logic elements, per se.
Subclass:
136
Having particular delay or sync:
This subclass is indented under subclass 131. Subject matter
including the control of a desired time relationship relative
to the output signal.
SEE OR SEARCH THIS CLASS, SUBCLASS:
141 for synchronizing, per se.
Subclass:
137
Having feedback:
This subclass is indented under subclass 131. Subject matter
wherein a portion of the output signal is returned to the
input.
Subclass:
138
Having temperature compensation:
This subclass is indented under subclass 131. Subject matter
wherein undesired circuit variations due to a thermal
condition are minimized.
SEE OR SEARCH THIS CLASS, SUBCLASS:
513 for miscellaneous temperature compensation circuits.
Subclass:
139
Having inductive load:
This subclass is indented under subclass 131. Subject matter
wherein the output is supplied to a device producing a
magnetic field which tends to inhibit any change in current
passing therethrough.
SEE OR SEARCH THIS CLASS, SUBCLASS:
110 for a circuit which enhances current driving capability
to an inductive device.
SEE OR SEARCH CLASS:
336, Inductor Devices, appropriate subclasses for generic
inductive devices.
Subclass:
140
With amplitude control:
This subclass is indented under subclass 131. Subject matter
including the maintenance or modification of output signal
magnitude.
SEE OR SEARCH THIS CLASS, SUBCLASS:
306 for miscellaneous amplitude control circuits.
SEE OR SEARCH CLASS:
330, Amplifiers, for amplifier circuits in general.
Subclass:
141
Synchronizing:
This subclass is indented under subclass 100. Subject matter
wherein a signal is produced which will (a) maintain a
predetermined phase or frequency relationship between two
sources of waves, one source being an excitation or standard
source (sync source) and the other source being changed to
achieve the predetermined relationship; (b) provide an
initiate or stop operation to a device at a predetermined
time; or (c) time (i.e., synchronize) the operation of some
electrical circuit or system.
SEE OR SEARCH THIS CLASS, SUBCLASS:
185 for circuits having one or more stable states.
231 for a phase shift which is less than the period of an
input signal.
261 for a time delay in producing an output waveform.
392 for a delay controlled switch.
SEE OR SEARCH CLASS:
219, Electric Heating, 108 for resistance welding circuits
which may contain timing means.
315, Electric Lamp and Discharge Devices: Systems, subclass
360 for timing circuits where the discharge device is the
ultimate load.
318, Electricity: Motive Power Systems subclass 62, 141+,
364+, 445, 700+, 725+, and 727+ for motor control circuits
containing time delay.
324, Electricity: Measuring and Testing, 160 for time or
speed measuring or determining.
326, Electronic Digital Logic Circuitry, 93 for logic stage
or gate synchronizing or timing.
331, Oscillators, 20 for synchronized automatic frequency
stabilized TV type oscillators, subclass 55 for synchronized
plural oscillators, subclass 87 for synchronized magnetron
oscillators, subclass 145 for synchronized free running
multivibrators, subclass 149 for synchronized free running
blocking oscillators, and subclass 153 for synchronized free
running relaxation oscillators in general.
348, Television, 500 for television synchronizing.
358, Facsimile and Static Presentation Processing, 409 for
facsimile synchronization.
375, Pulse or Digital Communications, 106 for data
communication synchronization.
Subclass:
142
Reset (e.g., initializing, starting, stopping, etc.):
This subclass is indented under subclass 141. Subject matter
wherein a device provides either an initiate or stop
operation at a predetermined interval from a predetermined
starting time.
SEE OR SEARCH THIS CLASS, SUBCLASS:
198 for similar circuits which establish a particular stable
state exclusive of synchronization.
SEE OR SEARCH CLASS:
326, Electronic Digital Logic Circuitry, subclass 94 for
prevention of a metastable state in digital logic.
Subclass:
143
Responsive to power supply:
This subclass is indented under subclass 142. Subject matter
wherein a circuit reacts to the supply of power thereto or
the removal of power therefrom.
(1) Note. The change in supplied power may be of any
duration.
SEE OR SEARCH THIS CLASS, SUBCLASS:
50 for amplitude discriminating, comparing, or selecting
without subsequent parameter control.
198 for initializing, resetting, or protecting a state of a
stable state circuit.
545 for miscellaneous signal protection or bias
preservation.
Subclass:
144
Using multiple clocks:
This subclass is indented under subclass 141. Subject matter
wherein plural square wave signals having precisely regulated
amplitude and frequency are utilized to achieve
synchronization.
Subclass:
145
Having different frequencies:
This subclass is indented under subclass 144. Subject matter
wherein the plural clocks have diverse repetition rates.
Subclass:
146
With feedback:
This subclass is indented under subclass 144. Subject matter
wherein a portion of the circuit output is returned to an
input.
(1) Note. Positive feedback occurs when a portion of an
output signal is fed back in phase with the input to increase
amplification and possibly cause oscillation.
(2) Note. Negative feedback occurs when a portion of an
output signal is fed back 180 degrees out of phase relative
to the input. This decreases amplification, stabilizes
circuit performance, and minimizes noise and distortion.
SEE OR SEARCH THIS CLASS, SUBCLASS:
155 for feedback synchronization in general.
Subclass:
147
Phase lock loop:
This subclass is indented under subclass 146. Subject matter
wherein a circuit compares the phase of the output signal
with a reference signal and converts any difference into a
correction voltage that changes the phase of the output so it
matches that of the reference or input signal.
SEE OR SEARCH THIS CLASS, SUBCLASS:
155 for phase lock loop type feedback synchronizing, in
general.
Subclass:
148
With charge pump:
This subclass is indented under subclass 147. Subject matter
wherein a device which pumps elemental positive or negative
electrical energy is included.
Subclass:
149
With variable delay means:
This subclass is indented under subclass 147. Subject matter
wherein means providing a changeable offset in time is
included.
SEE OR SEARCH THIS CLASS, SUBCLASS:
231 for phase shift or control.
261 for specific delay in producing an output waveform.
Subclass:
150
With digital element:
This subclass is indented under subclass 147. Subject matter
including a device performing Boolean algebra operations.
SEE OR SEARCH CLASS:
326, Electronic Digital Logic Circuitry, appropriate
subclasses for an electronic digital element, per se.
Subclass:
151
With counter:
This subclass is indented under subclass 144. Subject matter
which includes a device which can total the number of pulses
applied thereto.
SEE OR SEARCH CLASS:
377, Electrical Pulse Counters, Pulse Dividers, or Shift
Registers: Circuits and Systems, appropriate subclasses for
pulse counters, per se.
Subclass:
152
With choice between multiple delayed clocks:
This subclass is indented under subclass 144. Subject matter
wherein a single delayed clock is obtained from plural
candidates.
Subclass:
153
With delay means:
This subclass is indented under subclass 144. Subject matter
including means providing a distinct signal time offset.
SEE OR SEARCH THIS CLASS, SUBCLASS:
231 for phase shift or control.
261 for specific delay in producing an output waveform.
Subclass:
154
With feedforward:
This subclass is indented under subclass 141. Subject matter
wherein a portion of an input signal is advanced essentially
unchanged to an output stage of the synchronizing circuit.
SEE OR SEARCH THIS CLASS, SUBCLASS:
144 for feedforward type synchronization using multiple
clocks.
Subclass:
155
With feedback:
This subclass is indented under subclass 141. Subject matter
wherein a portion of the circuit output is returned to an
input.
SEE OR SEARCH THIS CLASS, SUBCLASS:
146 for feedback synchronization utilizing multiple clocks.
Subclass:
156
Phase lock loop:
This subclass is indented under subclass 155. Subject matter
wherein a circuit compares the phase of the output signal
with a reference signal and converts any difference into a
correction voltage that changes the phase of the output so it
matches that of the reference or input signal.
SEE OR SEARCH THIS CLASS, SUBCLASS:
147 for phase lock loop type feedback synchronizing using
multiple clocks.
Subclass:
157
With charge pump:
This subclass is indented under subclass 156. Subject matter
wherein a device which pumps elemental positive or negative
electrical energy is included.
Subclass:
158
With variable delay means:
This subclass is indented under subclass 156. Subject matter
wherein means providing a changeable offset in time is
included.
SEE OR SEARCH THIS CLASS, SUBCLASS:
231 for phase shift or control.
261 for specific delay in producing an output waveform.
Subclass:
159
With digital element:
This subclass is indented under subclass 156. Subject matter
including a device performing Boolean algebra operations.
SEE OR SEARCH CLASS:
326, Electronic Digital Logic Circuitry, appropriate
subclasses for an electronic digital element, per se.
Subclass:
160
With counter:
This subclass is indented under subclass 141. Subject matter
which includes a device which can total the number of pulses
applied thereto.
SEE OR SEARCH THIS CLASS, SUBCLASS:
151 for a counter in a synchronizing circuit using multiple
clocks.
SEE OR SEARCH CLASS:
377, Electrical Pulse Counters, Pulse Dividers, or Shift
Registers: Circuits and Systems, appropriate subclasses for
pulse counters, per se.
Subclass:
161
With delay means:
This subclass is indented under subclass 141. Subject matter
including means providing a distinct signal time offset.
SEE OR SEARCH THIS CLASS, SUBCLASS:
231 for phase shift or control.
261 for specific delay in producing an output waveform.
Subclass:
162
Having reference source:
This subclass is indented under subclass 141. Subject matter
wherein a clock is used as a standard.
Subclass:
163
By phase:
This subclass is indented under subclass 162. Subject matter
wherein the reference source controls the clock output of the
synchronizing circuit by a fractional part of the period of
an input signal periodic function or wave.
(1) Note. The period of a periodic function or wave is
defined as 360 electrical degrees.
Subclass:
164
Generating rectangular (e.g., clock, etc.) or pulse waveform
having random characteristic (e.g., random width, etc.):
This subclass is indented under subclass 100. Subject matter
including a probabilistic factor in the generation of a
pulsating waveform which is repetitive or intermittent and
where an individual pulse has negligible transition times.
SEE OR SEARCH CLASS:
331, Oscillators, subclass 78 for a free running random wave
or noise generator.
Subclass:
165
Regenerating or restoring rectangular (e.g., clock, etc.) or
pulse waveform:
This subclass is indented under subclass 100. Subject matter
wherein a pulse waveform which has undergone attenuation or
deformation is modified into an output pulse wave form whose
characteristics correspond to an original pulse waveform
prior to such attenuation or deformation.
(1) Note. Usually a feedback or regenerative system is
utilized to reshape the distorted pulse wave form.
SEE OR SEARCH CLASS:
178, Telegraphy, 70 for regenerative repeaters used in
telegraphy systems.
326, Electronic Digital Logic Circuitry, subclass 29 for
logic signal sensitivity or transmission integrity pulse
shaping.
330, Amplifiers, 75, 290, and 291+ for feedback amplifiers.
455, Telecommunications, 7 for signal repeaters that may
regenerate the repeated signal and which are used in radio
systems.
Subclass:
166
Having digital device (e.g., logic gate, flip-flop, etc.):
This subclass is indented under subclass 165. Subject matter
wherein a device which operates on binary signals is
included.
SEE OR SEARCH THIS CLASS, SUBCLASS:
185 for miscellaneous flip-flop circuits.
SEE OR SEARCH CLASS:
326, Electronic Digital Logic Circuitry, appropriate
subclasses for logic gates, per se.
Subclass:
167
Having network providing particular mathematical function
(e.g., integrator, etc.):
This subclass is indented under subclass 165. Subject matter
including circuitry which in response to a particular input
value produces a corresponding output value per a standard
mathematical relationship.
SEE OR SEARCH THIS CLASS, SUBCLASS:
334 for a circuit providing a mathematical relationship
between an input and an output.
Subclass:
168
Having inductive device (e.g., transformer, etc.):
This subclass is indented under subclass 165. Subject matter
including an element which has the property of opposing
current flow therethrough due to a resultant magnetic field.
SEE OR SEARCH CLASS:
336, Inductor Devices, appropriate subclasses for generic
inductive devices.
Subclass:
169
Having negative resistance device (e.g., tunnel diode,
etc.):
This subclass is indented under subclass 165. Subject matter
which includes a device having the property that, over a
portion of its characteristic I-V plot, increasing applied
device voltage results in a decrease in device current.
SEE OR SEARCH THIS CLASS, SUBCLASS:
568 for miscellaneous negative resistance circuits.
Subclass:
170
Slope control of leading or trailing edge of rectangular
(e.g., clock, etc.) or pulse waveform:
This subclass is indented under subclass 100. Subject matter
wherein the rise time or fall time of a pulse is maintained
constant or regulated in some manner.
SEE OR SEARCH THIS CLASS, SUBCLASS:
134 for slope or duration control of a sawtooth or
triangular waveform.
Subclass:
171
Output pulses having opposite polarities:
This subclass is indented under subclass 100. Subject matter
wherein an input pulse wave form consisting of a series of
pulses of a single polarity is converted to an output wave
form consisting of a plurality of pulses of alternate
polarities.
(1) Note. Such pulses are often referred to as bipolar.
Subclass:
172
Rectangular (e.g., clock, etc.) or pulse waveform width
control:
This subclass is indented under subclass 100. Subject matter
including maintaining constant or varying the length of
individual pulses in a pulsating waveform which is repetitive
or intermittent and wherein an individual pulse has
negligible transition times.
SEE OR SEARCH THIS CLASS, SUBCLASS:
31 for pulse width discriminating without subsequent
control.
398 for delay controlled switching with predetermined
activation time.
SEE OR SEARCH CLASS:
332, Modulators, 109 for modulation of pulse width by an
intelligence signal.
375, Pulse or Digital Communications, subclass 22 for
communication systems using pulse width modulation.
Subclass:
173
Pulse narrowing:
This subclass is indented under subclass 172. Subject matter
wherein the output pulse width or duration is decreased
relative to that at the input.
(1) Note. This is also known as pulse shortening.
SEE OR SEARCH THIS CLASS, SUBCLASS:
31 for pulse width discriminating.
174 for pulse lengthening or stretching.
Subclass:
174
Pulse broadening:
This subclass is indented under subclass 172. Subject matter
wherein the output pulse width or duration is increased
relative to that of the input.
(1) Note. This is also known as pulse stretching.
SEE OR SEARCH THIS CLASS, SUBCLASS:
31 for pulse width discriminating.
173 for pulse shortening or narrowing.
Subclass:
175
Duty cycle control:
This subclass is indented under subclass 172. Subject matter
wherein the ratio of pulse width to pulse separation in a
periodic wave is regulated.
SEE OR SEARCH THIS CLASS, SUBCLASS:
31 for pulse width or spacing discriminating without
subsequent control thereof.
Subclass:
176
Having digital device (e.g., logic gate, flip-flop, etc.):
This subclass is indented under subclass 172. Subject matter
wherein a device which operates on binary signals is
included.
SEE OR SEARCH THIS CLASS, SUBCLASS:
185 for miscellaneous flip-flop circuits.
SEE OR SEARCH CLASS:
326, Electronic Digital Logic Circuitry, appropriate
subclasses for logic gates, per se.
Subclass:
177
Having inductive device (e.g., transformer, etc.):
This subclass is indented under subclass 172. Subject matter
including an element which has the property of opposing
current flow therethrough due to a resultant magnetic field.
(1) Note. The inductive element may be distributed or
lumped.
SEE OR SEARCH CLASS:
336, Inductor Devices, appropriate subclasses for generic
inductive devices.
Subclass:
178
Rectangular (e.g., clock, etc.) or pulse waveform amplitude
control:
This subclass is indented under subclass 100. Subject matter
wherein the magnitude of an output pulse wave is regulated.
SEE OR SEARCH THIS CLASS, SUBCLASS:
306 for systems which regulate the height or amplitude of an
input wave, in general.
Subclass:
179
Gain:
This subclass is indented under subclass 178. Subject matter
wherein the ratio of output to input amplitude levels is
regulated.
SEE OR SEARCH THIS CLASS, SUBCLASS:
306 for miscellaneous amplitude control circuits.
SEE OR SEARCH CLASS:
330, Amplifiers, appropriate subclasses for generic
amplifying circuits.
Subclass:
180
Limiting, clipping, or clamping:
This subclass is indented under subclass 178. Subject matter
wherein the pulse has particular amplitude level
constraints.
SEE OR SEARCH THIS CLASS, SUBCLASS:
309 for limiting, clipping, or clamping circuits, in
general.
Subclass:
181
Electromagnetic pulse forming:
This subclass is indented under subclass 100. Subject matter
wherein a pulse of energy is produced which has
simultaneously varying electric and magnetic fields which are
at right angles to each other.
(1) Note. This includes, for example, the production of
pulsed RF or microwaves.
Subclass:
182
Delay line or capacitor storage element charged or discharged
through or by a relaxation oscillator type circuit to form
pulse:
This subclass is indented under subclass 100. Subject matter
including a distributed parameter wave conveying network or
analogous structure or capacitive retention device with a
respective charge or discharge path through an oscillator
which slowly charges and rapidly discharges an inductor or
capacitor through a resistor to form a pulse.
(1) Note. This subclass will not ordinarily contain subject
matter wherein the capacitor constitutes an element of a free
running relaxation oscillator circuit (such as provided for
in Class 331, Oscillators).
SEE OR SEARCH THIS CLASS, SUBCLASS:
183 for other systems utilizing storage or delay elements.
SEE OR SEARCH CLASS:
331, Oscillators, 143 for relaxation oscillators, per se.
333, Wave Transmission Lines and Networks, appropriate
subclasses for transmission lines, per se.
Subclass:
183
Delay line or capacitor storage element charges or discharges
through a tube to form pulse:
This subclass is indented under subclass 100. Subject matter
including a distributed parameter wave conveying network or
analogous structure or capacitive retention device adapted to
be charged or discharged through the electron path of an
electron space discharge device to form a pulse.
SEE OR SEARCH CLASS:
333, Wave Transmission Lines and Networks, appropriate
subclasses for transmission lines, per se.
Subclass:
184
Rectangular (e.g., clock, etc.) or pulse waveform generating
by conversion from input AC (e.g., sine, etc.) wave:
This subclass is indented under subclass 100. Subject matter
wherein an input signal from which the rectangular or pulse
output is derived comprises a signal having both positive and
negative portions.
(1) Note. Typically, the AC signal is a sinusoidal wave.
Subclass:
185
Particular stable state circuit (e.g., tristable, etc.):
This subclass is indented under subclass 100. Subject matter
comprising a circuit which will remain in a distinct current
conductive steady-state condition unless toggled therefrom by
a trigger input.
(1) Note. The condition to which the circuit may be toggled
may itself be stable or it may be unstable.
(2) Note. Detailed flip-flops, per se, generally are
contained herein; however, multifunctional or programmable
logic having a flip-flop is classified in Class 326,
subclasses 37+, and redundant logic having a flip-flop is
classified in Class 326, subclass 12.
SEE OR SEARCH THIS CLASS, SUBCLASS:
365 for gating of an unmodified input signal to an output.
SEE OR SEARCH CLASS:
326, Electronic Digital Logic Circuitry, subclass 12 for
redundant logic and flip-flop, subclasses 40 and 46 for
programmable logic and flip-flop, and subclasses 59+ for
logic circuits having three or more active states.
331, Oscillators, appropriate subclasses for free running
oscillators (e.g., astable circuits).
Subclass:
186
Superconductive (e.g., cryogenic, etc.):
This subclass is indented under subclass 185. Subject matter
wherein the circuit incorporates elements which exhibit a
marked decrease in electrical resistance (to essentially zero
ohms) at a temperature less than or equal to 30 K.
SEE OR SEARCH THIS CLASS, SUBCLASS:
366 for superconductive gating or switching.
527 for miscellaneous cryogenic device circuits.
SEE OR SEARCH CLASS:
326, Electronic Digital Logic Circuitry, 1 for
superconductive electronic digital logic circuits.
505, Superconductor Technology: Apparatus, Material,
Process, for high temperature (i.e., greater than 30 K)
superconductive apparatus, materials, or processes.
Subclass:
187
External effect device (e.g., light, heat, magnetic, or
mechanical force sensitive devices, etc.):
This subclass is indented under subclass 185. Subject matter
wherein an ambient force or field provides a toggling
stimulus to the stable state circuit.
SEE OR SEARCH THIS CLASS, SUBCLASS:
369 for an external effect controlled superconductive gating
circuit.
509 for miscellaneous external effect device circuits.
Subclass:
188
Minority carrier storage effect:
This subclass is indented under subclass 185. Subject matter
which utilizes or varies the concentration of electrons in
p-type material or holes in n-type material which accumulate
at a pn semiconductor junction.
SEE OR SEARCH THIS CLASS, SUBCLASS:
579 for miscellaneous circuits utilizing minority carrier
storage in a three or more electrode solid-state device.
585 for miscellaneous circuits utilizing a minority carrier
storage diode.
Subclass:
189
Storage diode (e.g., step recovery, etc.):
This subclass is indented under subclass 188. Subject matter
including a two-terminal unidirectionally conductive
semiconductor device having minority carriers which
accumulate at the pn junction when the diode is forward
biased and which are suddenly swept away as back biasing
increases to a certain point.
SEE OR SEARCH THIS CLASS, SUBCLASS:
585 for miscellaneous circuits using minority carrier
storage diodes.
Subclass:
190
With transformer or saturable core device:
This subclass is indented under subclass 185. Subject matter
including a device whose ratio of input voltage to output
voltage is directly proportional to the ratio of primary
windings to secondary windings therein or a magnetic core
reactor having reactance modified by varying the core
saturation through a superimposed unidirectional flux.
SEE OR SEARCH THIS CLASS, SUBCLASS:
300 for clock or pulse waveform generators utilizing a
saturable inductance.
SEE OR SEARCH CLASS:
307, Electrical Transmission or Interconnection Systems, 401
for nonlinear reactor systems (e.g., saturable) in electrical
transmission or interconnection systems.
336, Inductor Devices, appropriate subclasses for generic
inductive devices.
Subclass:
191
Blocking oscillator:
This subclass is indented under subclass 190. Subject matter
wherein the circuit includes transformer coupled feedback in
which output current flows for only one half cycle before the
oscillation is halted due to blocking of the input and the
oscillation is resumed after the input becomes unblocked.
SEE OR SEARCH CLASS:
331, Oscillators, subclass 112 for free running solid-state
blocking oscillators.
Subclass:
192
Negative resistance transistor (e.g., unijunction, etc.):
This subclass is indented under subclass 185. Subject matter
including a transistor whose characteristic on a current-
voltage plot has a portion with a downward slope.
SEE OR SEARCH THIS CLASS, SUBCLASS:
568 for miscellaneous negative resistance circuits.
Subclass:
193
Four or more layer device (e.g., trigistor, etc.):
This subclass is indented under subclass 192. Subject matter
wherein the transistor contains more than three adjacent
regions having differing conductivities.
SEE OR SEARCH THIS CLASS, SUBCLASS:
582 for miscellaneous four or more layer device circuits.
Subclass:
194
Zener or capacitive diode:
This subclass is indented under subclass 185. Subject matter
including a diode having a threshold voltage above which the
applied voltage must rise before the diode junction breaks
down allowing the current flow across the junction to
suddenly rise or including a voltage responsive two terminal
semiconductor device whose capacitance varies as a result of
changes in the space charge at a pn junction.
SEE OR SEARCH THIS CLASS, SUBCLASS:
302 for clock or pulse waveform generating utilizing storage
diodes.
584 for miscellaneous zener diode circuits.
586 for miscellaneous capacitive diode circuits.
SEE OR SEARCH CLASS:
257, Active Solid-State Devices (e.g., Transistors,
Solid-State Diodes), 603 for avalanche diodes, per se.
Subclass:
195
Negative resistance diode having "N"-shape characteristic on
I-V plot (e.g., tunnel diode, backward diode, etc.):
This subclass is indented under subclass 185. Subject matter
including a diode whose characteristic on a current versus
voltage plot (i.e., with the current plotted on the Y axis
and the voltage on the X axis) has an "N"-shape.
SEE OR SEARCH THIS CLASS, SUBCLASS:
570 for miscellaneous circuits using such diodes.
Subclass:
196
Negative resistance diode having "S"-shape characteristic on
I-V plot (e.g., four or more layer semiconductor device,
etc.):
This subclass is indented under subclass 185. Subject matter
including a diode whose characteristic on a current versus
voltage plot (i.e., with the current plotted on the Y axis
and the voltage on the X axis) has an "S"-shape.
SEE OR SEARCH THIS CLASS, SUBCLASS:
571 for miscellaneous circuits using such diodes.
Subclass:
197
Convertible circuit (e.g., bistable to monostable, D-type to
T-type, etc.):
This subclass is indented under subclass 185. Subject matter
wherein (a) a stable state circuit with an initial number of
stable states may be readily modified to one having a
different number of stable states or (b) a stable state
circuit with a fixed number of stable states can be readily
modified between differing input configurations.
Subclass:
198
Initializing, resetting, or protecting a steady state
condition:
This subclass is indented under subclass 185. Subject matter
including the establishment of a starting condition in a
stable state circuit, the restoration of a stable circuit to
a previous stable-state condition, or the prevention of
deterioration of an already established stable-state
condition.
SEE OR SEARCH THIS CLASS, SUBCLASS:
91 for amplitude detection circuits including details of
sampling or holding (e.g., capacitive storage element).
142 for a synchronizing type reset circuit.
315 for maintaining a predetermined input/output level ratio
by limiting, clipping, or clamping.
545 for protection of nonlinear solid-state signal or
circuit conditions against power or bias supply loss or
perturbations, per se, and see search notes thereunder.
SEE OR SEARCH CLASS:
326, Electronic Digital Logic Circuitry, subclass 94 for
logic metastable state prevention.
Subclass:
199
Circuit having only two stable states (i.e., bistable):
This subclass is indented under subclass 185. Subject matter
including a circuit with exactly two distinct
current-conductive steady-state conditions.
SEE OR SEARCH THIS CLASS, SUBCLASS:
227 for monostable (single stable state) circuits, per se.
291 for miscellaneous clock or pulse waveform generating.
365 for switching of an unmodified input to an output.
Subclass:
200
Dynamic bistable:
This subclass is indented under subclass 199. Subject matter
wherein a particular stable state is maintained by charge
storing elements which must be regularly recharged.
Subclass:
201
Complementary clock inputs:
This subclass is indented under subclass 200. Subject matter
which includes two inputs for clocks which are inverses of
each other.
Subclass:
202
Master-slave bistable latch:
This subclass is indented under subclass 199. Subject matter
wherein the bistable device includes a controlling circuit
section, otherwise known as the "master" stage and a
subsequent controlled section, known as the "slave" stage.
SEE OR SEARCH THIS CLASS, SUBCLASS:
216 for cross-coupled JK input bistable circuits in
general,
217 for cross-coupled RS input bistable circuits in
general.
SEE OR SEARCH CLASS:
377, Electrical Pulse Counters, Pulse Dividers, or Shift
Registers: Circuits and Systems, 115 for counters and
dividers including master-slave circuits as transfer means.
Subclass:
203
Including field-effect transistor:
This subclass is indented under subclass 202. Subject matter
which includes a unipolar transistor in which current
carriers are injected at a source terminal and pass to a
drain terminal through a channel of semiconductor material
whose conductivity depends largely on an electrical field
applied to the semiconductor from a control electrode
(gate).
(1) Note. In a unipolar transistor, the source to drain
current involves only one type of charge carrier (i.e., holes
in a p-type channel and electrons in an n-type channel).
(2) Note. Two types of FET structures are prevalent: (a)
an all-junction device, known as a junction FET or JFET
characterized by having heavily doped impurity regions of one
type (e.g., p-type material), known as gate regions, on both
sides of a second type semiconductor bar (e.g., n+ type
material) to form a pn junction, and (b) a device such as a
MOSFET/IGFET, consisting of a lightly doped substrate (e.g.,
p-type material) into which two highly doped regions (e.g.,
n+ type material) are diffused for forming source/drain
regions with the area therebetween becoming the channel for
current carriers (i.e., holes or electrons) and with a layer
of insulating material (e.g., SiO[subscrpt]2[end subscrpt])
grown over the channel surface for separating the channel
from a control (i.e., gate) electrode.
SEE OR SEARCH THIS CLASS, SUBCLASS:
581 for field-effect device circuits, per se.
SEE OR SEARCH CLASS:
257, Active Solid State Devices (e.g., Transistors,
Solid-State Diodes), 213 for field-effect devices, per se.
Subclass:
204
Including multi-emitter or multi-collector bipolar
transistor:
This subclass is indented under subclass 202. Subject matter
which includes a semiconductive device which has current
flowing through both n and p-type material and which has two
or more emitter regions or two or more collector regions.
Subclass:
205
Using hysteresis (e.g., Schmitt trigger, etc.):
This subclass is indented under subclass 199. Subject matter
wherein the input voltage required to cause a change from a
first stable state to a second stable state is distinctly
different from that required to cause a subsequent change
from the second stable state to the first stable state as a
result of feedback.
(1) Note. Electronic digital logic circuits which may
utilize hysteresis for noise margin enhancement are
classified with the logic circuits in Class 326.
SEE OR SEARCH THIS CLASS, SUBCLASS:
72 for analogous circuitry recited as an amplitude
comparator wherein an input is compared to a reference
derived therefrom.
74 for an input signal compared to plural fixed references.
SEE OR SEARCH CLASS:
326, Electronic Digital Logic Circuits, subclass 22 for
input noise margin enhancement logic circuits which may
utilize similar circuits.
Subclass:
206
Including field-effect transistor:
This subclass is indented under subclass 205. Subject matter
which includes a unipolar transistor in which current
carriers are injected at a source terminal and pass to a
drain terminal through a channel of semiconductor material
whose conductivity depends largely on an electrical field
applied to the semiconductor from a control electrode
(gate).
(1) Note. In a unipolar transistor, the source to drain
current involves only one type of charge carrier (i.e., holes
in a p-type channel and electrons in an n-type channel).
(2) Note. Two types of FET structures are prevalent: (a)
an all-junction device, known as a junction FET or JFET
characterized by having heavily doped impurity regions of one
type (e.g., p-type material), known as gate regions, on both
sides of a second type semiconductor bar (e.g., n+ type
material) to form a pn junction, and (b) a device such as a
MOSFET/IGFET, consisting of a lightly doped substrate (e.g.,
p-type material) into which two highly doped regions (e.g.,
n+ type material) are diffused for forming source/drain
regions with the area therebetween becoming the channel for
current carriers (i.e., holes or electrons) and with a layer
of insulating material (e.g., SiO[subscrpt]2[end subscrpt])
grown over the channel surface for separating the channel
from a control (i.e., gate) electrode.
SEE OR SEARCH THIS CLASS, SUBCLASS:
581 for field-effect device circuits, per se.
SEE OR SEARCH CLASS:
257, Active Solid-State Devices (e.g., Transistors,
Solid-State Diodes), 213 for field-effect devices, per se.
Subclass:
207
Including diverse solid-state devices (e.g., FET/ bipolar,
etc.):
This subclass is indented under subclass 199. Subject matter
wherein plural distinct types of semiconducting elements are
utilized.
(1) Note. Types of semiconducting elements include bipolar,
FET, SCR, etc.
SEE OR SEARCH CLASS:
257, Active Solid-State Devices (e.g., Transistors,
Solid-State Diodes), appropriate subclasses for diverse
solid-state device structure.
Subclass:
208
Including field-effect transistor:
This subclass is indented under subclass 199. Subject matter
which includes a unipolar transistor in which current
carriers are injected at a source terminal and pass to a
drain terminal through a channel of semiconductor material
whose conductivity depends largely on an electrical field
applied to the semiconductor from a control electrode
(gate).
(1) Note. In a unipolar transistor, the source to drain
current involves only one type of charge carrier (i.e., holes
in a p-type channel and electrons in an n-type channel).
(2) Note. Two types of FET structures are prevalent: (a)
an all-junction device, known as a junction FET or JFET
characterized by having heavily doped impurity regions of one
type (e.g., p-type material), known as gate regions, on both
sides of a second type semiconductor bar (e.g., n+ type
material) to form a pn junction, and (b) a device such as a
MOSFET/IGFET, consisting of a lightly doped substrate (e.g.,
p-type material) into which two highly doped regions (e.g.,
n+ type material) are diffused for forming source/drain
regions with the area therebetween becoming the channel for
current carriers (i.e., holes or electrons) and with a layer
of insulating material (e.g., SiO[subscrpt]2[end subscrpt])
grown over the channel surface for separating the channel
from a control (i.e., gate) electrode.
SEE OR SEARCH THIS CLASS, SUBCLASS:
51 for a sensing amplifier which may utilize an FET bistable
circuit.
581 for miscellaneous field-effect device circuits.
SEE OR SEARCH CLASS:
257, Active Solid-State Devices (e.g., Transistors,
Solid-State Diodes), 213 for field-effect devices, per se.
Subclass:
209
Including enhancement and depletion devices:
This subclass is indented under subclass 208. Subject matter
including (a) an FET device which permits current conduction
by attracting majority carriers to a channel by an
appropriate applied voltage and (b) an FET device which
inhibits current conduction by repelling majority carriers
away from a channel by an appropriate applied voltage.
Subclass:
210
CMOS:
This subclass is indented under subclass 208. Subject matter
wherein the FET is of the complementary
metal-oxide-semiconductor type.
Subclass:
211
With clock input:
This subclass is indented under subclass 210. Subject matter
which provides an input for a separate triggering source.
SEE OR SEARCH THIS CLASS, SUBCLASS:
291 for miscellaneous circuits which generate a clock or
pulse waveform.
SEE OR SEARCH CLASS:
326, Electronic Digital Logic Circuitry, 93 for clocking of
logic stages or gates.
Subclass:
212
With clock input:
This subclass is indented under subclass 208. Subject matter
which provides an input for a separate triggering source.
SEE OR SEARCH THIS CLASS, SUBCLASS:
291 for miscellaneous circuits which generate a clock or
pulse waveform.
SEE OR SEARCH CLASS:
326, Electronic Digital Logic Circuitry, 93 for clocking of
logic stages or gates.
Subclass:
213
Plural independent clock inputs (i.e., non-complementary):
This subclass is indented under subclass 212. Subject matter
wherein inputs accepting multiple distinct triggering sources
are present.
(1) Note. Clocks which are merely the inverse of each other
are not considered independent.
SEE OR SEARCH THIS CLASS, SUBCLASS:
291 for miscellaneous circuits which generate a clock or
pulse waveform.
Subclass:
214
Complementary transistors:
This subclass is indented under subclass 199. Subject matter
wherein the circuit includes a transistor of the pnp type and
a transistor of the npn type.
SEE OR SEARCH THIS CLASS, SUBCLASS:
576 for miscellaneous circuits using complementary
transistors.
Subclass:
215
Having at least two cross-coupling paths:
This subclass is indented under subclass 199. Subject matter
including two active devices, each capable of assuming a
distinct current-conductive stable state, the output of each
device being coupled to the input of the other.
SEE OR SEARCH THIS CLASS, SUBCLASS:
228 for a monostable circuit having cross-coupled paths.
Subclass:
216
JK type input:
This subclass is indented under subclass 215. Subject matter
wherein the multivibrator has a clock input and two
additional inputs (the "J" and "K" inputs) which jointly
determine the output state of the multivibrator at the
application of a clock pulse using the following guidelines:
(a) if both "J" and "K" are "HIGH", the multivibrator will
change state; (b) if "J" and "K" are both "LOW", the
multivibrator will maintain its current state; (c) if "J" =
"HIGH" and "K" = "LOW", the multivibrator will go to the
"HIGH" state; and (d) if "J" = "LOW" and "K" = "HIGH", the
multivibrator will go to the "LOW" state.
(1) Note. The "HIGH" state can be considered analogous to a
logic "1" and the "LOW" state can be considered analogous to
a logic "0."
Subclass:
217
RS or RST type input:
This subclass is indented under subclass 215. Subject matter
wherein the multivibrator has two inputs (the "R" and "S") in
the RS case and also a third (the "T" input) in the RST case
and which inputs determine the output state of the
multivibrator according to the following guidelines: (a) if
the "S" is "HIGH" then the multivibrator will go to the
"HIGH" state; (b) if the "R" is "HIGH", then the
multivibrator will go to the "LOW" state; and (c) if there is
a "T" input present and it is "HIGH", the multivibrator will
change state from its previous value.
(1) Note. A "HIGH" on both the "R" and the "S" inputs
simultaneously is not permitted.
(2) Note. The "HIGH" state can be considered analogous to a
logic "1" and the "LOW" state can be considered analogous to
a logic "0."
Subclass:
218
D type input:
This subclass is indented under subclass 215. Subject matter
wherein the multivibrator has a clock input and an additional
input (the "D" input) wherein the output state of the
multivibrator represents the state of the "D" input just
prior to the most recent clock pulse.
Subclass:
219
Particular device at input, output, or in cross-coupling
path:
This subclass is indented under subclass 215. Subject matter
including a specific active element at the multivibrator
signal insertion point, the signal extraction point, or in
the connection path between these two points.
Subclass:
220
With diode:
This subclass is indented under subclass 219. Subject matter
including a conventional two-terminal unidirectionally
conductive active element in the input circuit, the output
circuit, or a cross coupling path of the multivibrator.
SEE OR SEARCH CLASS:
257, Active Solid-State Devices (e.g., Transistors,
Solid-State Diodes), appropriate subclasses for diverse types
of diodes, per se.
Subclass:
221
Parallel RC network in cross-coupling path:
This subclass is indented under subclass 219. Subject matter
wherein a shunt-connected resistor and capacitor pair is
inserted in one of the mutually interconnected paths.
Subclass:
222
Resistor in cross-coupling path:
This subclass is indented under subclass 219. Subject matter
wherein a device which directly relates voltage to current is
inserted in one of the mutually interconnecting paths.
SEE OR SEARCH CLASS:
338, Electrical Resistors, appropriate subclasses for details
of electrical resistors.
Subclass:
223
Plural transistors of same conductivity type:
This subclass is indented under subclass 199. Subject matter
including multiple solid-state devices which are all of the
npn or all of the pnp variety.
Subclass:
224
With single semiconductor device:
This subclass is indented under subclass 199. Subject matter
wherein only one solid-state device is utilized.
Subclass:
225
With logic element (e.g., NOR gate, etc.):
This subclass is indented under subclass 199. Subject matter
wherein a device performing a Boolean algebraic function is
included.
SEE OR SEARCH CLASS:
326, Electronic Digital Logic Circuitry, appropriate
subclasses for logic gates, per se.
Subclass:
226
With single electron tube:
This subclass is indented under subclass 199. Subject matter
wherein a solitary active device is included which possesses
two or more spaced electrodes and in which current flow
therebetween comprises elemental negatively charged
particles.
SEE OR SEARCH CLASS:
313, Electric Lamp and Discharge Devices, appropriate
subclasses for electron tube structure, in general.
Subclass:
227
Monostable:
This subclass is indented under subclass 185. Subject matter
wherein the circuit has a single stable state which can be
momentarily changed to an unstable state by the application
of a triggering signal, but which will revert to the stable
state after a predetermined time.
SEE OR SEARCH THIS CLASS, SUBCLASS:
172 for a monostable used in pulse waveform width control.
199 for two stable state circuits (i.e.,
bistable).
291 for miscellaneous clock or pulse waveform generating.
Subclass:
228
Having cross-coupled paths:
This subclass is indented under subclass 227. Subject matter
including two circuit stages in which the output of each
stage is fed back to the input of the other.
SEE OR SEARCH THIS CLASS, SUBCLASS:
215 for a bistable circuit having at least two cross-coupled
paths.
Subclass:
229
Having differential circuitry:
This subclass is indented under subclass 227. Subject matter
including circuitry responsive to the offset between two
voltages or currents.
Subclass:
230
With external feedback (i.e., output to input):
This subclass is indented under subclass 227. Subject matter
wherein a portion of the output signal is returned to an
input terminal.
Subclass:
231
Phase shift by less than period of input:
This subclass is indented under subclass 100. Subject matter
wherein a fraction of the period of an input periodic wave
signal (with one period represented as 360 degrees along the
time axis) is maintained or shifted.
SEE OR SEARCH THIS CLASS, SUBCLASS:
2 for phase angle sensing without subsequent control.
141 for time or phase control of one signal to cause
synchronization with another signal.
261 for specific delay in producing output waveforms.
392 for delay controlled switching.
SEE OR SEARCH CLASS:
323, Electricity: Power Supply or Regulation Systems, 212
for electric power phase shift or control circuits.
331, Oscillators, 1 for automatic frequency stabilization
using phase of frequency sensing means and for phase lock
loop circuits in oscillator circuits and systems.
363, Electric Power Conversion Systems, appropriate
subclasses for phase conversion circuits with control or
error correction.
Subclass:
232
Dependent on frequency:
This subclass is indented under subclass 231. Subject matter
wherein the phase shift is varied dependent upon the number
or recurrences of a periodic input signal in a unit of time.
SEE OR SEARCH THIS CLASS, SUBCLASS:
39 for frequency selecting, comparing, or discriminating
without subsequent control.
Subclass:
233
Correction to specific phase shift:
This subclass is indented under subclass 231. Subject matter
wherein correction is made to an input signal phase shift to
ensure that the output signal has a predetermined phase
shift.
SEE OR SEARCH THIS CLASS, SUBCLASS:
165 for pulse or rectangular wave regeneration or
restoration.
237 for variable or adjustable phase shifting, in general.
Subclass:
234
Dependent on variable controlled phase shifts:
This subclass is indented under subclass 233. Subject matter
wherein the desired output phase shift is obtained by
applying changeable phase shifts to the input signal.
SEE OR SEARCH THIS CLASS, SUBCLASS:
235 for correction to specific phase shift by applying
plural fixed phase shifts to the input signal.
237 for variable or adjustable phase shifting in general.
Subclass:
235
Dependent on multiple fixed phase shifts:
This subclass is indented under subclass 233. Subject matter
wherein the desired output phase shift is obtained by
applying a plurality of unchanging phase shifts to the input
signal.
SEE OR SEARCH THIS CLASS, SUBCLASS:
234 for variable phase shifts applied to an input signal to
produce correction to a specific phase shift.
Subclass:
236
By phase comparator or detector:
This subclass is indented under subclass 233. Subject matter
wherein the phase shift change is effected by the output of a
circuit that obtains both the magnitude and sign of the phase
angle between two input voltages or currents.
SEE OR SEARCH THIS CLASS, SUBCLASS:
2 for phase discriminating or detecting without subsequent
control.
244 for a phase comparator or detector in a variable or
adjustable feedback circuit to control phase shift.
Subclass:
237
Variable or adjustable:
This subclass is indented under subclass 231. Subject matter
wherein the phase control is (a) continuously changed or (b)
modifiable (either automatically or in response to an
operator) to various fixed delays.
SEE OR SEARCH THIS CLASS, SUBCLASS:
270 for output waveform production delay via variable or
adjustable multiple outputs to effect a plurality of delay
intervals.
276 for output waveform production delay where a single
output has variable or selectable delay.
Subclass:
238
Quadrature related (i.e., 90 degrees):
This subclass is indented under subclass 237. Subject matter
wherein the variable or adjustable phase shift control
involves the state or condition of two related periodic
functions or two related points separated by a quarter of a
cycle or 90 electrical degrees.
SEE OR SEARCH THIS CLASS, SUBCLASS:
254 for quadrature related phase shift control which is not
variable or adjustable.
SEE OR SEARCH CLASS:
324, Electricity: Measuring and Testing, subclass 76.78 for
quadrature sensing, per se.
Subclass:
239
Non-overlapping multiple outputs:
This subclass is indented under subclass 237. Subject matter
wherein a variable or adjustable phase shift circuit produces
plural output clock type waves wherein no two such waves are
permitted to be "on" simultaneously.
SEE OR SEARCH THIS CLASS, SUBCLASS:
22 for pulse noncoincidence discriminating without
subsequent control.
23 for pulse coincidence discriminating without subsequent
control.
259 for non-overlapping multiple outputs in phase shift
circuitry in general.
Subclass:
240
Maintaining invariant amplitude:
This subclass is indented under subclass 237. Subject matter
wherein a variable or adjustable phase control device
produces an output signal having an unchanging amplitude
relative to the input signal.
SEE OR SEARCH THIS CLASS, SUBCLASS:
231 for unchanging phase shifts with invariant amplitude.
Subclass:
241
With counter or shift register:
This subclass is indented under subclass 237. Subject matter
including (a) a circuit which totals input pulses to produce
an output signal each time it receives a predetermined number
of input pulses or (b) a circuit which transfers its digital
contents along plural storage elements in a chain on the
application of an input pulse.
SEE OR SEARCH THIS CLASS, SUBCLASS:
241 for variable or adjustable phase shifting using a
counter or shift register.
265 for a counter in an active element or structure wherein
output waveform production delay is effected by the rising or
falling edge of an input.
273 for a counter in an active element or structure of a
multiple output, plural delay interval environment.
279 for a counter in an active element or structure of a
single output environment having a variable or selectable
delay.
286 for a counter with an active circuit element or
structure in output waveform production delay.
SEE OR SEARCH CLASS:
377, Electrical Pulse Counters, Pulse Dividers, or Shift
Registers: Circuits and Systems, appropriate subclasses for
counters or shift registers, per se.
Subclass:
242
Having multiple outputs:
This subclass is indented under subclass 241. Subject matter
wherein more than one output is produced.
SEE OR SEARCH THIS CLASS, SUBCLASS:
245 for a variable or adjustable phase shift with feedback
and multiple outputs.
247 for a variable or adjustable phase shift with a
differential amplifier and multiple outputs.
249 for a variable or adjustable phase shift with an adder
and multiple outputs.
251 for a variable or adjustable phase shift with an active
time delay element and multiple outputs.
253 for a variable or adjustable phase shift with a passive
time delay element and multiple outputs.
257 for multiple outputs wherein there is a 180 degree phase
difference between the input and output.
258 for a phase control circuit having multiple outputs, in
general.
Subclass:
243
With feedback:
This subclass is indented under subclass 237. Subject matter
wherein a portion of the output signal is returned to an
input.
(1) Note. Positive feedback occurs when a portion of an
output signal is fed back in phase with the input to increase
amplification and possibly cause oscillation.
(2) Note. Negative feedback occurs when a portion of an
output signal is fed back 180 degrees out of phase relative
to the input. This decreases amplification, stabilizes
circuit performance, and minimizes noise and distortion.
SEE OR SEARCH THIS CLASS, SUBCLASS:
154 for feedforward synchronization.
155 for feedback synchronization.
Subclass:
244
With phase comparator or detector:
This subclass is indented under subclass 243. Subject matter
including a circuit whose output represents both the
magnitude and sign of the phase angle between two input
voltages or currents.
SEE OR SEARCH THIS CLASS, SUBCLASS:
2 for phase comparing without subsequent control.
236 for a phase comparator or detector used in correcting a
specific phase shift.
Subclass:
245
Having multiple outputs:
This subclass is indented under subclass 243. Subject matter
wherein more than one output is produced.
SEE OR SEARCH THIS CLASS, SUBCLASS:
242 for a variable or adjustable phase shift with a counter
or shift register and multiple outputs.
247 for a variable or adjustable phase shift with a
differential amplifier and multiple outputs.
249 for a variable or adjustable phase shift with an adder
and multiple outputs.
251 for a variable or adjustable phase shift with an active
time delay element and multiple outputs.
253 for a variable or adjustable phase shift with a passive
time delay element and multiple outputs.
257 for multiple outputs where there is a 180 degree phase
difference between the input and output.
258 for a phase control circuit having multiple outputs, in
general.
Subclass:
246
With differential amplifier:
This subclass is indented under subclass 237. Subject matter
wherein a circuit amplifies only the differences between two
input signal voltages or currents and suppresses voltages or
currents appearing simultaneously on both inputs.
SEE OR SEARCH THIS CLASS, SUBCLASS:
266 for a differential amplifier in an active circuit
element or structure to effect output waveform production
delay via the rising or falling edge of a pulse signal.
274 for a differential amplifier in an active circuit
element or structure to effect output waveform production
delay of multiple outputs with a plurality of delay
intervals.
280 for a differential amplifier in an active circuit
element or structure to effect output waveform production
delay of a single output with variable or selectable delay.
287 for a differential amplifier in an active circuit
element or structure to effect output waveform production
delay.
Subclass:
247
Having multiple outputs:
This subclass is indented under subclass 246. Subject matter
wherein more than one output is produced.
SEE OR SEARCH THIS CLASS, SUBCLASS:
242 for a variable or adjustable phase shift with a counter
or shift register and multiple outputs.
245 for a variable or adjustable phase shift with feedback
and multiple outputs.
249 for a variable or adjustable phase shift with an adder
and multiple outputs.
251 for a variable or adjustable phase shift with an active
time delay element and multiple outputs.
253 for a variable or adjustable phase shift with a passive
time delay element and multiple outputs.
257 for multiple outputs where there is a 180 degree phase
difference between the input and output.
258 for a phase control circuit having multiple outputs, in
general.
Subclass:
248
With adder:
This subclass is indented under subclass 237. Subject matter
wherein a variable or adjustable device includes a circuit
which produces the sum of two or more quantities impressed on
it.
SEE OR SEARCH THIS CLASS, SUBCLASS:
361 for algebraic summing circuits.
SEE OR SEARCH CLASS:
708, Electrical Computers: Arithmetic Processing and
Calculating, subclass 670 for a digital computer providing
addition or subtraction.
Subclass:
249
Having multiple outputs:
This subclass is indented under subclass 248. Subject matter
wherein more than one output is produced.
SEE OR SEARCH THIS CLASS, SUBCLASS:
242 for a variable or adjustable phase shift with a counter
or shift register and multiple outputs.
245 for a variable or adjustable phase shift with feedback
and multiple outputs.
247 for a variable or adjustable phase shift with a
differential amplifier and multiple outputs.
251 for a variable or adjustable phase shift with an active
time delay element and multiple outputs.
253 for a variable or adjustable phase shift with a passive
time delay element and multiple outputs.
257 for multiple outputs where there is a 180 degree phase
difference between the input and output.
258 for a phase control circuit having multiple outputs, in
general.
Subclass:
250
With active time delay element:
This subclass is indented under subclass 237. Subject matter
wherein the time required for a signal to travel between two
points in a circuit is controlled by an element which
requires an external power supply other than the main input
signal for its operation.
SEE OR SEARCH THIS CLASS, SUBCLASS:
252 for a variable or adjustable phase shift with a passive
time delay element.
Subclass:
251
Having multiple outputs:
This subclass is indented under subclass 250. Subject matter
wherein more than one output is produced.
SEE OR SEARCH THIS CLASS, SUBCLASS:
242 for a variable or adjustable phase shift with a counter
or shift register and multiple outputs.
245 for a variable or adjustable phase shift with feedback
and multiple outputs.
247 for a variable or adjustable phase shift with a
differential amplifier and multiple outputs.
249 for a variable or adjustable phase shift with an adder
and multiple outputs.
253 for a variable or adjustable phase shift with a passive
time delay element and multiple outputs.
257 for multiple outputs where there is a 180 degree phase
difference between the input and output.
258 for a phase control circuit having multiple outputs, in
general.
Subclass:
252
With passive time delay element:
This subclass is indented under subclass 237. Subject matter
wherein the time required for a signal to travel between two
points in a circuit is controlled by an element powered only
by an input signal, without any bias voltage.
(1) Note. A passive element (such as a capacitor, resistor,
or inductor), does not add any amplification or gain (i.e.,
it presents some loss to the system).
SEE OR SEARCH THIS CLASS, SUBCLASS:
250 for a variable or adjustable phase shift with an active
time delay element.
Subclass:
253
Having multiple outputs:
This subclass is indented under subclass 252. Subject matter
wherein more than one output is produced.
SEE OR SEARCH THIS CLASS, SUBCLASS:
242 for a variable or adjustable phase shift with a counter
or shift register and multiple outputs.
245 for a variable or adjustable phase shift with feedback
and multiple outputs.
247 for a variable or adjustable phase shift with a
differential amplifier and multiple outputs.
249 for a variable or adjustable phase shift with an adder
and multiple outputs.
251 for a variable or adjustable phase shift with an active
time delay element and multiple outputs.
257 for multiple outputs where there is a 180 degree phase
difference between the input and output.
258 for a phase control circuit having multiple outputs, in
general.
Subclass:
254
Quadrature related (i.e., 90 degrees):
This subclass is indented under subclass 231. Subject matter
wherein the phase shift control includes the state or
condition of two related periodic functions or two related
points separated by a quarter of a cycle or 90 electrical
degrees.
SEE OR SEARCH THIS CLASS, SUBCLASS:
238 for quadrature related phase shift control which is
variable or adjustable.
255 for a phase shift control circuit where the output is in
quadrature with respect to the input.
SEE OR SEARCH CLASS:
324, Electricity: Measuring and Testing, subclass 76.78 for
quadrature sensing, per se.
Subclass:
255
90 degrees between input and output:
This subclass is indented under subclass 254. Subject matter
wherein the phase relationship between an output signal and
an input signal is separated by a quarter of a cycle or 90
electrical degrees.
SEE OR SEARCH THIS CLASS, SUBCLASS:
238 for quadrature related variable or adjustable phase
shift control.
SEE OR SEARCH CLASS:
324, Electricity: Measuring and Testing, subclass 76.78 for
quadrature sensing, per se.
Subclass:
256
Phase inversion (i.e., 180 degrees between input and
output):
This subclass is indented under subclass 231. Subject matter
wherein the phase relationship between the input and output
signal is separated by a half of a cycle or 180 electrical
degrees.
SEE OR SEARCH CLASS:
326, Electronic Digital Logic Circuitry, 104 for logical
inverters.
Subclass:
257
Multiple outputs:
This subclass is indented under subclass 256. Subject matter
wherein more than one output is produced.
SEE OR SEARCH THIS CLASS, SUBCLASS:
242 for a variable or adjustable phase shift with a counter
or shift register and multiple outputs.
245 for a variable or adjustable phase shift with feedback
and multiple outputs.
247 for a variable or adjustable phase shift with a
differential amplifier and multiple outputs.
249 for a variable or adjustable phase shift with an adder
and multiple outputs.
251 for a variable or adjustable phase shift with an active
time delay element and multiple outputs.
253 for a variable or adjustable phase shift with a passive
time delay element and multiple outputs.
258 for a phase control circuit having multiple outputs, in
general.
Subclass:
258
Multiple outputs:
This subclass is indented under subclass 231. Subject matter
wherein more than one output is produced.
SEE OR SEARCH THIS CLASS, SUBCLASS:
242 for a variable or adjustable phase shift with a counter
or shift register and multiple outputs.
245 for a variable or adjustable phase shift with feedback
and multiple outputs.
247 for a variable or adjustable phase shift with a
differential amplifier and multiple outputs.
249 for a variable or adjustable phase shift with an adder
and multiple outputs.
251 for a variable or adjustable phase shift with an active
time delay element and multiple outputs.
253 for a variable or adjustable phase shift with a passive
time delay element and multiple outputs.
257 for multiple outputs where there is a 180 degree phase
difference between the input and output.
Subclass:
259
Non-overlapping:
This subclass is indented under subclass 258. Subject matter
wherein a phase shift circuit produces plural output clock
type waves where no two such waves are permitted to be "on"
simultaneously.
SEE OR SEARCH THIS CLASS, SUBCLASS:
22 for pulse noncoincidence discriminating without
subsequent control.
23 for pulse coincidence discriminating without subsequent
control.
239 for non-overlapping multiple outputs in a variable or
adjustable phase shift control circuit.
Subclass:
260
Producing AC power control:
This subclass is indented under subclass 231. Subject matter
wherein an output alternating current signal is controlled
either by a phase shift or by suppressing output dependent
upon some phase.
(1) Note. A flow of electricity which reaches a maximum in
one direction, decreases to zero, then reverses itself and
reaches a maximum in the opposite direction and this cycle is
continuously repeated is alternating current.
SEE OR SEARCH THIS CLASS, SUBCLASS:
306 for amplitude control.
365 for switching or gating of an AC signal.
530 for miscellaneous circuits with specific source of
supply or bias voltage.
SEE OR SEARCH CLASS:
323, Electricity: Power Supply or Regulation Systems,
appropriate subclasses for power supply regulation of a
single source coupled to a single load.
Subclass:
261
Having specific delay in producing output waveform:
This subclass is indented under subclass 100. Subject matter
wherein an output signal is obtained at a predetermined time
interval subsequent to the application of an input or control
or initiating signal to a system.
(1) Note. Delay controlled switching is classified below
with gating circuits.
SEE OR SEARCH THIS CLASS, SUBCLASS:
141 for time or phase control of one signal to cause
synchronization with another signal.
231 for a signal phase shift which is less than the input
signal period.
336 for the integration of an input signal.
392 for a delay controlled switch.
Subclass:
262
Including significant compensation (e.g., temperature
compensated delay, etc.):
This subclass is indented under subclass 261. Subject matter
wherein undesired changes in circuit operation due to, for
example, temperature changes, component structural
differences, or power supply fluctuations are offset.
(1) Note. Regulating systems for controlling a load as well
as compensating circuits for protecting systems and
semiconductor structures against failure are found in Class
323.
SEE OR SEARCH THIS CLASS, SUBCLASS:
509 for miscellaneous external effect circuits.
538 for miscellaneous supply or bias circuits with
significant compensation or stabilization.
SEE OR SEARCH CLASS:
323, Electricity: Power Supply or Regulation Systems, 220,
234+, 299+, 304+, and 318+ for load controlled or regulated
systems.
326, Electronic Digital Logic Circuitry, subclass 14 for
logic circuits which maintain a fail-safe condition against
circuit breakdown and subclasses 21+ for signal sensitivity
or transmission integrity in logic circuitry.
Subclass:
263
Delay interval set by rising or falling edge:
This subclass is indented under subclass 261. Subject matter
wherein the delay time is determined by either (a) the
interval between the occurrence of leading or trailing edges
of a pulse signal or (b) the amount of time for the leading
or trailing edge of a pulse waveform to rise or fall to a
particular value.
SEE OR SEARCH THIS CLASS, SUBCLASS:
2 for phase characteristic selecting and particularly
subclasses 3+ for phase angle sensing (e.g., lead/lag
discriminators).
172 for controlling the duration of pulse signals (e.g.,
pulse stretching) in pulse generators.
SEE OR SEARCH CLASS:
318, Electricity: Motive Power Systems, subclass 62 for
motor speed control with time delay; subclasses 141+ for
generator-fed motor systems controlled by time delay;
subclasses 283+ for time delay for motor-reversing; and
subclasses 445+ for time delay control, per se, (e.g.,
automatic starting/stopping).
388, Electricity: Motor Control Systems, cross-reference art
collection 921 for running-speed control systems including a
time delay.
Subclass:
264
Having specific active circuit element or structure (e.g.,
FET, complementary transistors, etc.):
This subclass is indented under subclass 263. Subject matter
including a particular circuit element or structure requiring
an external power supply other than the main input signal for
its operation and which produces some dynamic function change
(e.g., amplification) of the applied input electrical signal
basic characteristic.
(1) Note. Examples of active circuit elements are
transistors, tunnel diodes, or SCR's.
SEE OR SEARCH THIS CLASS, SUBCLASS:
268 for a passive circuit element or structure in output
waveform production delay wherein the delay interval is set
by the rising or falling of an input pulse.
272 for an active circuit element or structure in output
waveform production delay with multiple outputs with a
plurality of delay intervals.
278 for an active circuit element or structure in output
waveform production delay with a single output with a
variable or selectable delay.
283 for a passive circuit element or structure in output
waveform production delay with a single output with a
variable or selectable delay.
285 for an active circuit element or structure for output
waveform production delay.
290 for a passive circuit element or structure in output
waveform production delay.
Subclass:
265
With counter:
This subclass is indented under subclass 264. Subject matter
wherein a circuit is included which totals input pulses to
produce an output signal each time it receives a
predetermined number of input pulses.
SEE OR SEARCH THIS CLASS, SUBCLASS:
241 for a variable or adjustable phase shift using a counter
or shift register.
273 for a counter in an active element or structure of a
multiple output, plural delay environment.
279 for a counter in an active element or structure of a
single output environment having a variable or selectable
delay.
286 for a counter with an active circuit element or
structure in output waveform production delay.
SEE OR SEARCH CLASS:
377, Electrical Pulse Counters, Pulse Dividers, or Shift
Registers: Circuits and Systems, appropriate subclasses for
counters, per se.
Subclass:
266
Differential amplifier:
This subclass is indented under subclass 264. Subject matter
wherein a circuit amplifies only the differences between two
input signal voltages or currents and suppresses voltages or
currents appearing simultaneously on both inputs.
SEE OR SEARCH THIS CLASS, SUBCLASS:
246 for variable or adjustable phase shift control using a
differential amplifier.
274 for a differential amplifier in an active circuit
element or structure to effect output waveform production
delay of multiple outputs with a plurality of delay
intervals.
280 for a differential amplifier in an active circuit
element or structure to effect output waveform production
delay of a single output with variable or selectable delay.
287 for a differential amplifier in an active circuit
element or structure to effect output waveform production
delay.
Subclass:
267
Electron tube:
This subclass is indented under subclass 264. Subject matter
including a gas filled or partially or fully evacuated
(vacuum) device which regulates current flow between spaced
electrodes.
SEE OR SEARCH THIS CLASS, SUBCLASS:
275 for circuits using an electron tube within an active
circuit element or structure having multiple outputs with a
plurality of delay intervals.
282 for time interval control using an electron tube within
an active circuit element or structure having a single output
with variable or selectable delay.
289 for circuits using an electron tube in a specific active
circuit element or structure providing output waveform
production delay.
Subclass:
268
Having passive circuit element or structure (e.g., RLC
circuit, etc.):
This subclass is indented under subclass 263. Subject matter
wherein a circuit element or structure is powered only by an
input signal without any bias voltage and produces a desired
modification of the input signal without adding any
amplification or gain (i.e., it presents some loss to a
system).
(1) Note. Examples of passive devices are capacitors,
resistors, and inductors.
SEE OR SEARCH THIS CLASS, SUBCLASS:
264 for an active circuit element or structure in output
waveform production delay wherein the delay interval is set
by the rising or falling of an input pulse.
272 for an active circuit element or structure in output
waveform production delay with multiple outputs with a
plurality of delay intervals.
278 for an active circuit element or structure in output
waveform production delay with a single output with a
variable or selectable delay.
283 for a passive circuit element or structure in output
waveform production delay with a single output with a
variable or selectable delay.
285 for an active circuit element or structure for output
waveform production delay.
290 for a passive circuit element or structure in output
waveform production delay.
Subclass:
269
Multiple outputs with plurality of delay intervals:
This subclass is indented under subclass 261. Subject matter
including plural outputs each having its own amount of
delay.
SEE OR SEARCH THIS CLASS, SUBCLASS:
401 for time-delay circuits for controlling a switching or
powering operation having plural switching elements.
403 for gating of plural parallel controlled signal paths.
Subclass:
270
Variable or adjustable:
This subclass is indented under subclass 269. Subject matter
wherein the multiple delay intervals are either (a)
continuously changing or (b) changeable, automatically or in
response to an operator.
SEE OR SEARCH THIS CLASS, SUBCLASS:
237 for variable or adjustable phase shift control.
276 for output waveform production delay where a single
output has variable or adjustable delay.
Subclass:
271
Including delay line or charge transfer device:
This subclass is indented under subclass 269. Subject matter
wherein at least one time interval is derived from the time
of propagation of a signal through a transmission line type
means (e.g., shift register, cascade-connected nonlinear
amplifier stages, charge transfer element, etc.).
SEE OR SEARCH THIS CLASS, SUBCLASS:
277 for a delay line type structure within a single output
circuit having variable or selectable delay intervals.
284 for a delay line structure or charge transfer device
which is utilized in output waveform production delay.
SEE OR SEARCH CLASS:
326, Electronic Digital Logic Circuitry, subclass 61 for
logic circuits using an insulated gate charge transfer
device.
Subclass:
272
Having specific active circuit element or structure (e.g.,
FET, complementary transistors, etc.):
This subclass is indented under subclass 269. Subject matter
including a particular circuit element or structure requiring
an external power supply other than the main input signal for
its operation and which produces some dynamic function change
(e.g., amplification) of the applied input electrical signal
basic characteristic.
(1) Note. Examples of active circuit elements are
transistors, tunnel diodes, SCRs, or ICs.
SEE OR SEARCH THIS CLASS, SUBCLASS:
264 for an active circuit element or structure in output
waveform production delay wherein the delay interval is set
by the rising or falling of an input pulse.
268 for a passive circuit element or structure in output
waveform production delay wherein the delay interval is set
by the rising or falling of an input pulse.
278 for an active circuit element or structure in output
waveform production delay with a single output with a
variable or selectable delay.
283 for a passive circuit element or structure in output
waveform production delay with a single output with a
variable or selectable delay.
285 for an active circuit element or structure for output
waveform production delay.
290 for a passive circuit element or structure in output
waveform production delay.
Subclass:
273
With counter:
This subclass is indented under subclass 272. Subject matter
wherein a circuit is included which totals input pulses to
produce an output signal each time it receives a
predetermined number of input pulses.
SEE OR SEARCH THIS CLASS, SUBCLASS:
241 for a variable or adjustable phase shift using a counter
or shift register.
265 for a counter in an active element or structure wherein
output waveform production delay is effected by the rising or
falling edge of an input.
279 for a counter in an active element or structure of a
single output environment having a variable or selectable
delay.
286 for a counter with an active circuit element or
structure in output waveform production delay.
SEE OR SEARCH CLASS:
377, Electrical Pulse Counters, Pulse Dividers, or Shift
Registers: Circuits and Systems, appropriate subclasses for
counters, per se.
Subclass:
274
Differential amplifier:
This subclass is indented under subclass 272. Subject matter
including a circuit which amplifies only the differences
between two input signal voltages or currents and suppresses
voltages or currents appearing simultaneously on both
inputs.
SEE OR SEARCH THIS CLASS, SUBCLASS:
246 for variable or adjustable phase shift control using a
differential amplifier.
266 for a differential amplifier in an active circuit
element or structure to effect output waveform production
delay via the rising or falling edge of a pulse signal.
280 for a differential amplifier in an active circuit
element or structure to effect output waveform production
delay of a single output with variable or selectable delay.
287 for a differential amplifier in an active circuit
element or structure to effect output waveform production
delay.
Subclass:
275
Electron tube:
This subclass is indented under subclass 272. Subject matter
including a gas filled or partially or fully evacuated
(vacuum) device which regulates current flow between spaced
electrodes.
SEE OR SEARCH THIS CLASS, SUBCLASS:
267 for the use of an electron tube within an active circuit
element or structure to control the output waveform
production delay via the rising or falling edge of an input
pulse.
282 for output waveform production delay using an electron
tube within an active circuit element or structure having a
single output with variable or selectable delay.
Subclass:
276
Single output with variable or selectable delay:
This subclass is indented under subclass 261. Subject matter
including one output where the delay time is adjustable or
may be chosen from multiple possibilities.
SEE OR SEARCH THIS CLASS, SUBCLASS:
237 for variable or adjustable phase shift control.
270 for multiple outputs which have a plurality of variable
or adjustable delay intervals.
Subclass:
277
Including delay line or charge transfer device:
This subclass is indented under subclass 276. Subject matter
wherein the delay interval is derived from the time of
propagation of a signal through a transmission line type
means (e.g., shift register, cascade-connected nonlinear
amplifier stages, charge transfer element, etc.).
SEE OR SEARCH THIS CLASS, SUBCLASS:
271 for a delay line type structure within an output
waveform production delay circuit having multiple outputs and
a plurality of delay intervals.
SEE OR SEARCH CLASS:
326, Electronic Digital Logic Circuitry, subclass 61 for
logic circuits using an insulated gate charge transfer
device.
Subclass:
278
Having specific active circuit element or structure (e.g.,
complementary transistors, etc.):
This subclass is indented under subclass 276. Subject matter
including a particular circuit element or structure requiring
an external power supply other than the main input signal for
its operation and which produces some dynamic function change
(e.g., amplification) of the applied input electrical signal
basic characteristic.
(1) Note. Examples of active circuit elements are
transistors, tunnel diodes, SCRs, or ICs.
SEE OR SEARCH THIS CLASS, SUBCLASS:
264 for an active circuit element or structure in output
waveform production delay wherein the delay interval is set
by the rising or falling of an input pulse.
268 for a passive circuit element or structure in output
waveform production delay wherein the delay interval is set
by the rising or falling of an input pulse.
272 for an active circuit element or structure in output
waveform production delay with multiple outputs with a
plurality of delay intervals.
283 for a passive circuit element or structure in output
waveform production delay with a single output with a
variable or selectable delay.
285 for an active circuit element or structure for output
waveform production delay.
290 for a passive circuit element or structure in output
waveform production delay.
Subclass:
279
With counter:
This subclass is indented under subclass 278. Subject matter
wherein a circuit is included which totals input pulses to
produce an output signal each time it receives a
predetermined number of input pulses.
SEE OR SEARCH THIS CLASS, SUBCLASS:
241 for a variable or adjustable phase shift using a counter
or shift register.
265 for a counter in an active element or structure wherein
output waveform production delay is effected by the rising or
falling edge of an input.
273 for a counter in an active element or structure of a
multiple output, plural delay interval environment.
286 for a counter with an active circuit element or
structure in output waveform production delay.
SEE OR SEARCH CLASS:
377, Electrical Pulse Counters, Pulse Dividers, or Shift
Registers: Circuits and Systems, appropriate subclasses for
counters, per se.
Subclass:
280
Differential amplifier:
This subclass is indented under subclass 278. Subject matter
including a circuit which amplifies only the differences
between two input signal voltages or currents and suppresses
voltages or currents appearing simultaneously on both
inputs.
SEE OR SEARCH THIS CLASS, SUBCLASS:
246 for variable or adjustable phase shift control using
differential amplifier.
266 for a differential amplifier in an active circuit
element or structure to effect output waveform production
delay via the rising or falling edge of a pulse signal.
274 for a differential amplifier in an active circuit
element or structure to effect output waveform production
delay of multiple outputs with a plurality of delay
intervals.
287 for a differential amplifier in an active circuit
element or structure to effect output waveform production
delay.
SEE OR SEARCH CLASS:
330, Amplifiers, for electrical amplifiers, in general.
Subclass:
281
Field-effect transistor:
This subclass is indented under subclass 278. Subject matter
including a unipolar transistor in which current carriers are
injected at a source terminal and pass to a drain terminal
through a channel of semiconductor material whose
conductivity depends largely on an electrical field applied
to the semiconductor from a control electrode (gate).
(1) Note. In a unipolar transistor, the source to drain
current involves only one type of charge carrier (i.e., holes
in a p-type material channel and electrons in an n-type
material channel.
(2) Note. Two types of FET structures are prevalent: (a)
an all-junction device, known as a junction FET or JFET
characterized by having heavily doped impurity regions of one
type (e.g., p-type material), known as gate regions, on both
sides of a second type semiconductor bar (e.g., n+ type
material) to form a pn junction, and (b) a device such as a
MOSFET/IGFET, consisting of a lightly doped substrate (e.g.,
p-type material) into which two highly doped regions (e.g.,
n+ type material) are diffused for forming source/drain
regions with the area therebetween becoming the channel for
current carriers (i.e., holes or electrons) and with a layer
of insulating material (e.g., SiO[subscrpt]2[end subscrpt])
grown over the channel surface for separating the channel
from a control (i.e., gate) electrode.
Subclass:
282
Electron tube:
This subclass is indented under subclass 278. Subject matter
including a gas filled, or partially or fully evacuated
(vacuum) device which regulates current flow between spaced
electrodes.
SEE OR SEARCH THIS CLASS, SUBCLASS:
267 for the use of an electron tube within an active circuit
element or structure to control the output waveform
production delay via the rising or falling edge of the input
pulse.
275 for output waveform production delay using an electron
tube within an active circuit element or structure having
multiple outputs with a plurality of delay intervals.
Subclass:
283
Having specific passive circuit element or structure (e.g.,
RLC circuit, etc.):
This subclass is indented under subclass 276. Subject matter
wherein a circuit element or structure is powered only by an
input signal, without any bias voltage and produces a desired
modification on the input signal without adding any
amplification or gain (i.e., it presents some loss to a
system).
(1) Note. Examples of passive devices are capacitors,
resistors, and inductors.
SEE OR SEARCH THIS CLASS, SUBCLASS:
264 for an active circuit element or structure in output
waveform production delay wherein the delay interval is set
by the rising or falling of an input pulse.
268 for a passive circuit element or structure in output
waveform production delay wherein the delay interval is set
by the rising or falling of an input pulse.
272 for an active circuit element or structure in output
waveform production delay with multiple outputs with a
plurality of delay intervals.
278 for an active circuit element or structure in output
waveform production delay with a single output with a
variable or selectable delay.
285 for an active circuit element or structure for output
waveform production delay.
290 for a passive circuit element or structure in output
waveform production delay.
Subclass:
284
Including delay line or charge transfer device:
This subclass is indented under subclass 261. Subject matter
wherein the time interval is derived from the time of
propagation of a signal through a transmission line type
means (e.g., shift register, cascade-connected nonlinear
amplifier stages, charge transfer element, etc.).
(1) Note. Passive delay lines are included in this
subclass.
SEE OR SEARCH THIS CLASS, SUBCLASS:
182 and 183, for pulse generators utilizing passive delay
lines.
SEE OR SEARCH CLASS:
326, Electronic Digital Logic Circuitry, subclass 61 for
logic circuits using an insulated gate charge transfer device
and subclasses 93+ for logic function circuits including one
or more stages clocked synchronously for transmitting
signals.
333, Wave Transmission Lines and Networks, 138 for passive
delay networks, per se.
365, Static Information Storage and Retrieval, subclass 76
for recirculating storage systems including delay lines.
377, Electrical Pulse Counters, Pulse Dividers, or Shift
Registers: Circuits and Systems, 64 for shift registers, in
general.
Subclass:
285
Having specific active circuit element or structure (e.g.,
complementary transistors, etc.):
This subclass is indented under subclass 261. Subject matter
including a particular circuit element or structure requiring
an external power supply other than the main input signal for
its operation and which produces some dynamic function change
(e.g., amplification) of the applied input electrical signal
basic characteristic.
(1) Note. Examples of active circuit elements are
transistors, tunnel diodes, or SCR's.
SEE OR SEARCH THIS CLASS, SUBCLASS:
264 for an active circuit element or structure in output
waveform production delay wherein the delay interval is set
by the rising or falling of an input pulse.
272 for an active circuit element or structure in output
waveform production delay with multiple outputs with a
plurality of delay intervals.
268 for a passive circuit element or structure in output
waveform production delay wherein the delay interval is set
by the rising or falling of an input pulse.
278 for an active circuit element or structure in output
waveform production delay with a single output with a
variable or selectable delay.
283 for a passive circuit element or structure in output
waveform production delay with a single output with a
variable or selectable delay.
290 for a passive circuit element or structure in output
waveform production delay.
Subclass:
286
With counter:
This subclass is indented under subclass 285. Subject matter
wherein a circuit is included which totals input pulses to
produce an output signal each time it receives a
predetermined number of input pulses.
SEE OR SEARCH THIS CLASS, SUBCLASS:
241 for a variable or adjustable phase shift using a counter
or shift register.
265 for a counter in an active element or structure wherein
output waveform production delay is effected by the rising or
falling edge of an input signal.
273 for a counter in an active element or structure of a
multiple output, plural delay environment.
279 for a counter in an active element or structure of a
single output environment having a variable or selectable
delay.
SEE OR SEARCH CLASS:
377, Electrical Pulse Counters, Pulse Dividers, or Shift
Registers: Circuits and Systems, appropriate subclasses for
counters, per se.
Subclass:
287
Differential amplifier:
This subclass is indented under subclass 285. Subject matter
including a circuit which amplifies only the differences
between two input voltages or currents and suppresses
voltages or currents appearing simultaneously on both
inputs.
SEE OR SEARCH THIS CLASS, SUBCLASS:
246 for variable or adjustable phase shift control using a
differential amplifier.
266 for a differential amplifier in an active circuit
element or structure to effect output waveform production
delay via the rising or falling edge of a pulse signal.
274 for a differential amplifier in an active circuit
element or structure to effect output waveform production
delay of multiple outputs with a plurality of delay
intervals.
280 for a differential amplifier in an active circuit
element or structure to effect output waveform production
delay of a single output with variable or selectable delay.
Subclass:
288
Field-effect transistor:
This subclass is indented under subclass 285. Subject matter
including a unipolar transistor in which current carriers are
injected at a source terminal and pass to a drain terminal
through a channel of semiconductor material whose
conductivity depends largely on an electrical field applied
to the semiconductor from a control electrode (gate).
(1) Note. In a unipolar transistor, the source to drain
current involves only one type of charge carrier (i.e., holes
in a p-type material channel and electrons in an n-type
material channel.
(2) Note. Two types of FET structures are prevalent: (a)
an all-junction device, known as a junction FET or JFET
characterized by having heavily doped impurity regions of one
type (e.g., p-type material), known as gate regions, on both
sides of a second type semiconductor bar (e.g., n+ type
material) to form a pn junction, and (b) a device such as a
MOSFET/IGFET, consisting of a lightly doped substrate (e.g.,
p-type material) into which two highly doped regions (e.g.,
n+ type material) are diffused for forming source/drain
regions with the area therebetween becoming the channel for
current carriers (i.e., holes or electrons) and with a layer
of insulating material (e.g., SiO[subscrpt]2[end subscrpt])
grown over the channel surface for separating the channel
from a control (i.e., gate) electrode.
Subclass:
289
Electron tube:
This subclass is indented under subclass 285. Subject matter
including a gas filled or partially or fully evacuated
(vacuum) device which regulates current flow between spaced
electrodes.
SEE OR SEARCH CLASS:
333, Wave Transmission Lines and Networks, 138 for passive
delay networks.
Subclass:
290
Having specific passive circuit element or structure (e.g.,
RLC circuit, etc.):
This subclass is indented under subclass 261. Subject matter
wherein a circuit element or structure is powered only by an
input signal, without any bias voltage, and produces a
desired modification on the input signal without adding any
amplification or gain (i.e., it presents some loss to a
system).
(1) Note. Examples of passive devices are capacitors,
resistors, and inductors.
SEE OR SEARCH THIS CLASS, SUBCLASS:
264 for an active circuit element or structure in output
waveform production delay wherein the delay interval is set
by the rising or falling of an input pulse.
268 for a passive circuit element or structure in output
waveform production delay wherein the delay interval is set
by the rising or falling of an input pulse.
272 for an active circuit element or structure in output
waveform production delay with multiple outputs with a
plurality of delay intervals.
278 for an active circuit element or structure in output
waveform production delay with a single output with a
variable or selectable delay.
283 for a passive circuit element or structure in output
waveform production delay with a single output with a
variable or selectable delay.
285 for an active circuit element or structure for output
waveform production delay.
Subclass:
291
Clock or pulse waveform generating:
This subclass is indented under subclass 100. Subject matter
wherein an output waveshape is produced which exhibits two
distinct amplitude levels and where the transition
therebetween is rapid.
(1) Note. The systems contained in this subclass and the
indented subclasses are very similar to those found in Class
331, Oscillators; the distinction being that the systems in
Class 331 are self sustaining or free running while those in
this class are not capable of self-sustained continuous
operation.
(2) Note. Bias circuits of the pulsing type which establish
device operating points are classified with the bias
circuits.
SEE OR SEARCH THIS CLASS, SUBCLASS:
104 for systems which convert AC to corresponding DC at an
unloaded output.
185 for stable state circuits (e.g., mono stable or
bistable) which may provide a pulse.
309 for systems wherein the output represents the input
waveform with the peaks thereof clipped or limited between
certain levels.
336 for integrating networks.
544 for circuits with power conservation or pulse type
source of supply or bias.
554 for a switched capacitor filter having an input which
accepts a clock signal.
SEE OR SEARCH CLASS:
128, Surgery, 419 for systems wherein an alternating current
is converted to pulses of energy for application to the human
body.
178, Telegraphy, appropriate subclasses for pulse producing
systems wherein the pulses are representative of a telegraph
code, particularly 17 for such systems where a perforated
tape or other automatic device controls the production of the
pulses, subclasses 2+ for systems where a keyboard is used to
produce the pulses.
307, Electrical Transmission or Interconnection Systems, 106
for class appropriate waveform or wave shape determinative or
pulse producing systems and subclasses 401+ for nonlinear
reactor systems.
315, Electric Lamp and Discharge Devices: Systems, 137 for
polyphase AC supply and subclasses 246+ for gaseous tube
systems with pulsating or AC supply.
324, Electricity: Measuring and Testing, subclass 119 for
measuring systems involving rectification.
331, Oscillators, appropriate subclasses, for self-sustained
generators, particularly 20 for TV oscillators with
automatic frequency stabilization, subclass 61 for
oscillators with plural outputs of diverse waveforms,
subclass 75 for oscillators combined with wave shaping
networks in the output circuit, subclass 87 for magnetron
type oscillators with pulse forming means in the control
circuit thereof, subclasses 143+ for pulse forming networks
of the relaxation oscillators type, subclasses 165+ for shock
excited resonant circuit with pulse type keying, and
subclasses 172+ for synchronizing, triggering, or pulsing
circuits for oscillators.
332, Modulators, 106 for pulse modulators where the nature
of the pulses is varied in an arbitrary manner.
333, Wave Transmission Lines and Networks, subclass 20 for
wave shaping systems utilizing a passive element.
340, Communications: Electrical, appropriate subclasses,
particularly 825.57, for pulse responsive selective systems;
subclasses 870.19+ for pulse modulation telemetering systems;
and subclasses 287+ for electric signaling system with
transmission of a train of pulse signals.
341, Code Data Generation or Conversion, 20 and 173+ for a
pulse code transmitter, and subclasses 50+ for digital to
digital code converters.
342, Communications, Directive Radio Wave Systems and Devices
(e.g., Radar, Radio Navigation), appropriate subclasses for
pulse reflected wave systems, particularly 118 and 147+ for
radar type systems involving pulse generating for determining
distance or direction.
361, Electricity: Electrical Systems and Devices, 182 for
single and plural relays which are frequency responsive,
subclass 185 for phase responsive relays, and subclass 186
for pulse responsive relays.
363, Electric Power Conversion Systems, 13 for current
conversion (i.e., rectification or derectification) systems.
370, Multiplex Communications, subclass 205, 212, and 213 for
transmitting different messages involving pulse modulation.
375, Pulse or Digital Communications, subclass 37 for
miscellaneous telegraph systems using pulsating currents and
subclasses 59+ for transmitters with pulse production.
378, X-Ray or Gamma Ray Systems or Devices subclass 104 for
X-ray electrical systms utilizing rectifying means with AC or
pulsating supply.
379, Telephonic Communication, appropriate subclasses for
telephone pulse producing systems.
Subclass:
292
Clock fault compensation or redundant clocks:
This subclass is indented under subclass 291. Subject matter
wherein clock accuracy is ensured by correcting for
anticipated or actual clock errors.
(1) Note. This may be achieved by providing multiple clocks
which can, if necessary, be substituted for a defective
clock.
SEE OR SEARCH THIS CLASS, SUBCLASS:
526 for miscellaneous redundant circuits.
SEE OR SEARCH CLASS:
326, Electronic Digital Logic Circuitry, 10 for redundant
logic circuitry.
Subclass:
293
With plural paths in network:
This subclass is indented under subclass 291. Subject matter
including multiple channels between a signal input terminal
and one or more output terminals.
SEE OR SEARCH THIS CLASS, SUBCLASS:
38 69+, 293, 407+, and 415+, for other systems with plural
paths or channels therein.
Subclass:
294
With common output:
This subclass is indented under subclass 293. Subject matter
wherein the output of each of the plural paths or channels is
fed to a common final output point.
SEE OR SEARCH CLASS:
370, Multiplex Communications, appropriate subclasses for
similar subject matter used with multiplexing.
Subclass:
295
Plural outputs:
This subclass is indented under subclass 291. Subject matter
wherein multiple separate output waveforms are produced and
appear at respective output terminals.
(1) Note. The separate outputs may be of similar or diverse
wave shape or sign.
Subclass:
296
Plural clock outputs with multiple inputs:
This subclass is indented under subclass 295. Subject matter
wherein multiple clock waveforms are derived at circuit
outputs from plural clock inputs.
Subclass:
297
Clock bus:
This subclass is indented under subclass 295. Subject matter
wherein the clock is applied to a distribution network which
distributes a plural series of precisely timed, repetitive
voltage pulses to plural devices.
SEE OR SEARCH THIS CLASS, SUBCLASS:
293 for clock generators having plural paths.
SEE OR SEARCH CLASS:
326, Electronic Digital Logic Circuitry, subclass 86 for bus
current driving in a logic circuit.
Subclass:
298
Single clock output with multiple inputs:
This subclass is indented under subclass 291. Subject matter
wherein plural inputs are utilized to produce the single
clock output.
Subclass:
299
Single clock output with single clock or data input:
This subclass is indented under subclass 291. Subject matter
wherein one series of precisely timed, repetitive voltage
pulses of fixed frequency and amplitude or a signal
containing information is the sole input for creating a
single clock output.
SEE OR SEARCH THIS CLASS, SUBCLASS:
295 for plural output clock generating.
Subclass:
300
With saturable inductance:
This subclass is indented under subclass 291. Subject matter
including a magnetic core reactor having reactance modified
by varying the core saturation through a superimposed
unidirectional flux.
SEE OR SEARCH THIS CLASS, SUBCLASS:
181 for pulse generating systems comprising electromagnetic
pulse forming.
SEE OR SEARCH CLASS:
307, Electrical Transmission or Interconnection Systems, 401
for nonlinear reactor, (e.g., inductor) systems, in general.
330, Amplifiers, subclass 8 for magnetic amplifiers
involving saturable core devices.
336, Inductor Devices, appropriate subclasses for structural
details of induction devices and particularly 155 for
saturable type inductors.
Subclass:
301
With electron beam type tube:
This subclass is indented under subclass 291. Subject matter
including at least one electron space discharge device whose
performance depends upon the formation and control of one or
more rays of elemental negatively charged particles.
Subclass:
302
With storage diode:
This subclass is indented under subclass 291. Subject matter
which incorporates a two-terminal semiconductive device
having minority carriers which accumulate at a pn junction
when the diode is forward biased and which are suddenly swept
away after back biasing increases to a certain point.
SEE OR SEARCH THIS CLASS, SUBCLASS:
194 for stable state circuits utilizing capacitive diodes.
586 for capacitive diode circuits, in general.
SEE OR SEARCH CLASS:
257, Active Solid-State Devices (e.g., Transistors,
Solid-State Diodes), 595 for voltage variable capacitance
diodes, per se.
Subclass:
303
With rectifier:
This subclass is indented under subclass 291. Subject matter
including a device transforming an AC signal to a
corresponding DC signal by a device permitting only
unidirectional current flow.
SEE OR SEARCH THIS CLASS, SUBCLASS:
28 for systems for determining or selecting desired pulses
from a group of pulses by polarity and in which a rectifier
may be utilized.
104 for systems for converting from an AC input to a
corresponding DC voltage at an unloaded output and see the
search notes thereunder.
336 for integrating networks in which a rectifier may be
utilized.
SEE OR SEARCH CLASS:
307, Electrical Transmission or Interconnection Systems,
subclass 107 for pulse producing systems of the passive type
and utilizing rectification or derectification.
315, Electric Lamp and Discharge Devices: Systems, 200 for
discharge devices or rectifiers in the supply circuit for
gaseous tubes and subclass 272 for pulsating or AC supply
systems for gaseous tubes and including a rectifier in the
control circuit.
Subclass:
304
With inductive device (e.g., transformer, etc.):
This subclass is indented under subclass 291. Subject matter
which includes an element which has the property of opposing
current flow therethrough due to a resultant magnetic field.
SEE OR SEARCH CLASS:
336, Inductor Devices, appropriate subclasses for generic
inductive devices.
Subclass:
305
With gas tube:
This subclass is indented under subclass 291. Subject matter
which incorporates an electron discharge device where a small
amount of gas is ionized to permit current flow.
Subclass:
306
Amplitude control:
This subclass is indented under subclass 100. Subject matter
wherein the amplitude of an input signal waveform is
modified, maintained, or regulated to produce the desired
output signal.
SEE OR SEARCH THIS CLASS, SUBCLASS:
50 for voltage signal amplitude comparison (e.g., amplitude
responsive pulse selecting systems).
90 for systems wherein the output is a function of the
amplitude difference of two points on a wave.
178 for amplitude control systems of a pulse or rectangular
wave output.
335 for differentiating networks.
336 for integrating networks.
356 for the recited algebraic product of two input signals
which may be analogous to gain control circuits.
551 for unwanted signal suppression and particularly
subclasses 552+ for such signal suppression provided by an
active filter.
SEE OR SEARCH CLASS:
323, Electricity: Power Supply or Regulation Systems, 234
for a power supply which is output level responsive.
330, Amplifiers, subclass 96, 123, 127+, and 278+ for
automatic signal level control or for amplitude limiting of
amplifier power supplies.
331, Oscillators, 182 for amplitude control of oscillator
output.
332, Modulators, 149 for amplitude modulation systems.
333, Wave Transmission Lines and Networks, subclass 14 for
amplitude compression and expansion systems (i.e.,
companders) and subclasses 15, 16, 17.1+, and 81+ for passive
element attenuator systems for controlling signal amplitude.
348, Television, 571 for amplitude control used in
television receivers.
455, Telecommunications, 234 for automatic volume control
systems used in radio receivers.
Subclass:
307
Baseline or DC offset correction:
This subclass is indented under subclass 306. Subject matter
wherein the drift of a reference direct current component of
a signal is compensated.
SEE OR SEARCH THIS CLASS, SUBCLASS:
165 for rectangular or pulse waveform regeneration.
178 for rectangular or pulse waveform amplitude control.
Subclass:
308
Variable attenuator:
This subclass is indented under subclass 306. Subject matter
wherein an input signal amplitude is diminished by an
adjustable but typically unchanging factor.
SEE OR SEARCH CLASS:
330, Amplifiers, appropriate subclasses for amplifying
circuits, in general.
Subclass:
309
By limiting, clipping, or clamping:
This subclass is indented under subclass 306. Subject matter
wherein (a) the output signal amplitude is constrained by a
maximum allowed level, a minimum allowed level or both or (b)
the upper or lower amplitude extreme of the output signal is
maintained at a particular level.
SEE OR SEARCH CLASS:
323, Electricity: Power Supply or Regulation Systems, 234
for a power supply which is output level responsive.
330, Amplifiers, subclass 96, 123, 127+, and 278+ for
automatic signal level and gain control or amplitude limiting
of amplifier power supplies.
331, Oscillators, 182 for amplitude control of oscillator
output.
333, Wave Transmission Lines and Networks, subclass 14 for
amplitude compression and expansion systems (i.e.,
companders); and subclasses 15, 16, 17.1+, and 81+ for
passive element attenuator systems which control signal
amplitude.
348, Television, 571 for amplitude control such as limiting
or clamping in a television receiver.
375, Pulse or Digital Communications, subclass 34, 60, and
99+ for noise reduction in pulse code modulation,
transmitters, and receivers and subclass 98 for automatic
gain control in receivers.
455, Telecommunications, 218, 278+, 296+, and 501+ for noise
or interference elimination in analog communication and
subclasses 234+ for attenuators and automatic gain control
circuits in receiver or analog modulated frequency
converters.
Subclass:
310
Transient or signal noise reduction:
This subclass is indented under subclass 309. Subject matter
wherein the limiting, clipping, or clamping lessens or
eliminates an intermittent spuriously generated component
from a signal.
(1) Note. Recited noise override of the type associated
with gating or switching is classified with the gating or
switching area below.
SEE OR SEARCH THIS CLASS, SUBCLASS:
379 for gating circuits having improvement of signal
transmission integrity or spurious noise override.
551 for miscellaneous unwanted signal suppression.
SEE OR SEARCH CLASS:
326, Electronic Digital Logic Circuitry, 21 for signal
sensitivity enhancement or signal transmission integrity in
digital logic.
361, Electricity: Electrical Systems and Devices, subclass
110 and 111 for transient protection in systems or devices.
375, Pulse or Digital Communications, subclass 34, 51, 57,
58, 60, and 99+ for noise reduction in pulse code modulated
systems, systems using pulsating current, pulse transmitters,
AC or pulse systems or receivers.
381, Electrical Audio Signal Processing Systems and Devices,
subclass 13, 83, 93, and 94.1+ for noise or feedback
suppression in audio systems.
455, Telecommunications, 63, 114, 218+, 278+, 283+, 296+, and
501+ for noise or interference elimination in analog
communication systems (e.g., transmitter and receiver at
separate stations or transceivers, etc.).
704, Data Processing: Speech Signal Processing, Linguistics,
Language Translation, and Audio Compression/Decompression,
subclass 233 for detection of speech in noise.
714, Error Detection/Correction and Fault Detection/Recovery,
subclasses 761-763 +, 781 and 788 for correcting digital
data errors caused by random or burst noise signals.
Subclass:
311
By filtering:
This subclass is indented under subclass 310. Subject matter
wherein the limiting, clipping or clamping of a signal
transient is provided by a circuit which offers little
opposition to some frequencies or DC while blocking or
attenuating other frequencies.
SEE OR SEARCH THIS CLASS, SUBCLASS:
329 for tuned circuit limiters.
552 for miscellaneous active filters which suppress an
unwanted signal.
SEE OR SEARCH CLASS:
307, Electrical Transmission or Interconnection Systems,
subclass 105 for harmonic filters and neutralizers other
than nonlinear active device types.
333, Wave Transmission Lines and Networks, 17.1 through 20
for filters (usually passive) for controlling amplitude,
impedance matching, and wave shaping; subclasses 24+ for
passive wave filters; and subclasses 213+ for active devices
determining passive filter characteristics.
375, Pulse or Digital Communications, subclass 103 for
filtering in receivers.
455, Telecommunications, 296 and 339 for noise or
interference elimination and for filter coupling or
decoupling of stages in receiver or analog modulated signal
frequency converter systems.
708, Electrical Computers: Arithmetic Processing and
Calculating, 300 for digital filters and subclass 819 for
filtering by an analog computer.
Subclass:
312
By feedback limiting-clamping:
This subclass is indented under subclass 310. Subject matter
wherein transient or signal noise reduction is performed in a
return path between an output terminal and an input
terminal.
SEE OR SEARCH THIS CLASS, SUBCLASS:
316 for feedback circuits to maintain a constant
input-output ratio relationship.
323 for feedback limiting-clamping circuits, in general.
332 for amplitude output level control with feedback.
SEE OR SEARCH CLASS:
330, Amplifiers, 75, 156, 258, 260, 265, 270, 271, 282, 290,
and 291+ for amplifiers with linear feedback.
Subclass:
313
Using 3 or more terminal type nonlinear devices only:
This subclass is indented under subclass 310. Subject matter
wherein the circuit includes one or more elements having an
output which is not in direct proportion to its input and
having more than two electrodes as the only type of active
element.
Subclass:
314
Using diode type nonlinear devices only:
This subclass is indented under subclass 310. Subject matter
wherein the circuit includes one or more two-terminal
unidirectionally conductive devices as the only type of
active element.
SEE OR SEARCH THIS CLASS, SUBCLASS:
312 for feedback controlled limiting-clamping.
318 for diode limiting, clipping, or clamping in the input
or output circuits.
323 for Schottky barrier feedback limiting-clamping
circuits.
325 for limiting, clipping, or clamping in general which
utilizes only diode devices.
583 for miscellaneous solid-state diode circuits.
SEE OR SEARCH CLASS:
326, Electronic Digital Logic Circuitry, 130 and 133+ for
diode logic circuits.
Subclass:
315
Providing constant input/output amplitude level ratio:
This subclass is indented under subclass 309. Subject matter
including maintenance of the ratio of the input to output
signal magnitudes to a fixed value.
SEE OR SEARCH THIS CLASS, SUBCLASS:
331 for amplitude control circuits which maintain a constant
level output.
SEE OR SEARCH CLASS:
330, Amplifiers, 278 for linear amplifier automatic signal
level and gain control and subclasses 96 and 123 for
amplitude limiting of amplifier power supplies in linear
systems.
Subclass:
316
By feedback control:
This subclass is indented under subclass 315. Subject matter
wherein a circuit is controlled by a signal returned along a
path between an output terminal and an input terminal.
SEE OR SEARCH THIS CLASS, SUBCLASS:
312 for feedback limiting-clamping circuit for reducing
unwanted noise signals.
323 for feedback limiting-clamping circuits, per se.
Subclass:
317
Distortion compensation:
This subclass is indented under subclass 309. Subject matter
wherein an undesired waveform modification is corrected or
reduced by imposing amplitude constraints on the waveform.
SEE OR SEARCH THIS CLASS, SUBCLASS:
133 for distortion control in a sawtooth or triangular
waveform.
165 for regenerating or restoring a rectangular waveform.
551 for miscellaneous unwanted signal suppression.
Subclass:
318
In input or output circuit:
This subclass is indented under subclass 309. Subject matter
wherein the limiting, clipping, or clamping device is a
component of either a signal insertion or extraction point of
a circuit.
SEE OR SEARCH THIS CLASS, SUBCLASS:
309 for limiting, clipping, or clamping to control output
wave shape characteristics, generally.
310 for limiting, clipping, or clamping to remove unwanted
noise signals.
Subclass:
319
For interstage coupling:
This subclass is indented under subclass 318. Subject matter
wherein the limiting, clipping, or clamping permits the
joining of two or more circuit sections together.
SEE OR SEARCH THIS CLASS, SUBCLASS:
333 for miscellaneous interstage coupling.
SEE OR SEARCH CLASS:
326, Electronic Digital Logic Circuitry, subclass 62 for
interface circuits for logic functions, per se.
Subclass:
320
Using diode:
This subclass is indented under subclass 319. Subject matter
including one or more two-terminal unidirectionally
conductive devices.
SEE OR SEARCH THIS CLASS, SUBCLASS:
314 for diodes used in shunt-type limiting, clipping, or
clamping for reducing unwanted noise signals.
325 for limiting, clipping, or clamping circuits, per se,
which utilize only diodes.
SEE OR SEARCH CLASS:
257, Active Solid-State Devices (e.g., Transistors,
Solid-State Diodes), appropriate subclasses for diverse types
of diodes.
Subclass:
321
Clamping of output to voltage level:
This subclass is indented under subclass 318. Subject matter
wherein the maximum or minimum value of an output signal is
held to a particular voltage level.
Subclass:
322
Of output current:
This subclass is indented under subclass 318. Subject matter
including apparatus which regulates the value of the current
in the output.
SEE OR SEARCH THIS CLASS, SUBCLASS:
540 for current regulating in a miscellaneous circuit having
a specific source of power supply or bias voltage.
Subclass:
323
Feedback:
This subclass is indented under subclass 309. Subject matter
wherein a limiting, clipping, or clamping structure is in a
return path between an output terminal and an input
terminal.
SEE OR SEARCH THIS CLASS, SUBCLASS:
312 for feedback limiting, clipping, or clamping in reducing
unwanted noise signals.
316 for feedback circuits to maintain a constant
input-output ratio relationship.
332 for constant output amplitude control with feedback.
SEE OR SEARCH CLASS:
330, Amplifiers, 75, 156, and 282+ for linear feedback
amplifiers.
Subclass:
324
By using diverse-type nonlinear devices:
This subclass is indented under subclass 309. Subject matter
wherein plural, unlike-in-kind, nonlinear devices are
utilized.
SEE OR SEARCH THIS CLASS, SUBCLASS:
310 for diverse-type limiting, clipping, or clamping to
reduce unwanted noise signals.
318 for diverse-type limiting, clipping, or clamping in
either the input or output circuit.
SEE OR SEARCH CLASS:
330, Amplifiers, subclass 299 for combined diverse-type
linear gain semiconductor devices.
Subclass:
325
Using only diode active elements:
This subclass is indented under subclass 309. Subject matter
wherein the limiting, clipping, or clamping utilizes a
two-terminal unidirectionally conductive device as the sole
active circuit device.
SEE OR SEARCH THIS CLASS, SUBCLASS:
314 for diode shunt-type limiting, clipping, or clamping to
reduce unwanted noise signals.
318 for diode limiting, clipping, or clamping in the input
or output circuits.
SEE OR SEARCH CLASS:
257, Active Solid-State Devices (e.g., Transistor,
Solid-State Diodes), appropriate subclasses for diverse types
of diodes.
Subclass:
326
Avalanche or negative resistance device (e.g., zener diode,
tunnel diode, etc.):
This subclass is indented under subclass 325. Subject matter
wherein at least one of the diode elements exhibits a sharp
increase of current flow with increasing reverse bias applied
thereto or has an IV characteristic with a portion where an
increase in applied voltage results in a decrease of current
therethrough.
SEE OR SEARCH THIS CLASS, SUBCLASS:
310 for negative resistance device limiting, clipping, or
clamping which reduce transient noise signals.
SEE OR SEARCH CLASS:
257, Active Solid-State Devices (e.g., Transistor,
Solid-State Diodes), appropriate subclasses for solid-state
devices, per se, and particularly 603 for avalanche diodes,
per se.
Subclass:
327
Using only transistor active elements:
This subclass is indented under subclass 309. Subject matter
wherein the limiting, clipping, or clamping utilizes a three
or more terminal solid-state device as the sole active
circuit device type.
SEE OR SEARCH THIS CLASS, SUBCLASS:
310 for limiting, clipping, or clamping to reduce unwanted
noise signals.
315 for circuits providing constant input-output ratio
level.
574 for special three or more electrode solid-state devices
and circuits, per se.
SEE OR SEARCH CLASS:
257, Active Solid-State Devices (e.g., Transistors,
Solid-State Diodes), appropriate subclasses for solid-state
devices, per se.
326, Electronic Digital Logic Circuitry, appropriate
subclasses for transistor logic circuit arrangements.
Subclass:
328
Field-effect type device:
This subclass is indented under subclass 327. Subject matter
which includes a unipolar transistor in which current
carriers are injected at a source terminal and pass to a
drain terminal through a channel of semiconductor material
whose conductivity depends largely on an electrical field
applied to the semiconductor from a control electrode
(gate).
(1) Note. In a unipolar transistor, the source to drain
current involves only one type of charge carrier (i.e., holes
in a p-type channel and electrons in an n-type channel).
(2) Note. Two types of FET structures are prevalent: (a)
an all-junction device, known as a junction FET or JFET
characterized by having heavily doped impurity regions of one
type (e.g., p-type material), known as gate regions, on both
sides of a second type semiconductor bar (e.g., n+ type
material) to form a pn junction, and (b) a device such as a
MOSFET/IGFET, consisting of a lightly doped substrate (e.g.,
p-type material) into which two highly doped regions (e.g.,
n+ type material) are diffused for forming source/drain
regions with the area therebetween becoming the channel for
current carriers (i.e., holes or electrons) and with a layer
of insulating material (e.g., SiO[subscrpt]2[end subscrpt])
grown over the channel surface for separating the channel
from a control (i.e., gate) electrode.
SEE OR SEARCH THIS CLASS, SUBCLASS:
51 for a sensing amplifier which may utilize an FET bistable
circuit.
310 for controlled shunt-type limiting, clipping, or
clamping with one or more field-effect transistor devices to
reduce unwanted noise signals.
581 for field-effect device circuits, per se.
SEE OR SEARCH CLASS:
257, Active Solid-State Devices (e.g., Transistors,
Solid-State Diodes), 213 for field-effect devices, per se.
Subclass:
329
With tuned circuit:
This subclass is indented under subclass 309. Subject matter
including an inductive/capacitive network having a particular
resonant frequency.
SEE OR SEARCH THIS CLASS, SUBCLASS:
532 for power or bias supply systems with a wave filter.
SEE OR SEARCH CLASS:
334, Tuners, appropriate subclasses for radio wave tuning
circuitry and devices.
Subclass:
330
With rectifier or nonlinear impedance:
This subclass is indented under subclass 309. Subject matter
including a device converting alternating current to direct
current or an impedance where the voltage to current ratio is
not directly related.
SEE OR SEARCH THIS CLASS, SUBCLASS:
104 and 531, for systems with detector or rectifier.
SEE OR SEARCH CLASS:
363, Electric Power Conversion Systems, 13 for electrical
power conversion rectifiers or inverters.
Subclass:
331
Maintaining constant level output:
This subclass is indented under subclass 306. Subject matter
wherein the amplitude of an output waveform is kept at a
fixed level independently of the amplitude of the input
waveform.
SEE OR SEARCH THIS CLASS, SUBCLASS:
315 for a circuit providing constant input/output amplitude
level ratio.
Subclass:
332
With feedback:
This subclass is indented under subclass 331. Subject matter
wherein a correction voltage is returned from an output
circuit to a control electrode in the input.
SEE OR SEARCH THIS CLASS, SUBCLASS:
131 for systems utilizing cathode feedback.
185 and 590+, for tube systems with feedback.
SEE OR SEARCH CLASS:
330, Amplifiers, appropriate subclasses, particularly 75,
156, 258, 260, 265, 270, 271, 282, 290, and 291+ for
amplifiers with linear feedback.
Subclass:
333
Interstage coupling (e.g., level shift, etc.):
This subclass is indented under subclass 306. Subject matter
wherein interconnection of two diverse circuits having
different ranges of acceptable signal values is made
possible.
SEE OR SEARCH CLASS:
326, Electronic Digital Logic Circuitry 62 for logic
interface circuits.
Subclass:
334
SPECIFIC INPUT TO OUTPUT FUNCTION:
This subclass is indented under the class definition.
Subject matter wherein an output is proportional to a
nonlinear mathematical expression of an input signal.
(1) Note. Characteristically the input signal is continuous
and slowly varying with the output signal usually bearing a
mathematical relationship to it.
(2) Note. Boolean algebra functions and linear amplifiers
are excluded from this subclass.
(3) Note. The input signals in this subclass do not contain
information (data) of any kind. For data processing, see
Search Class below.
SEE OR SEARCH THIS CLASS, SUBCLASS:
1 for discriminating systems.
560 for nonlinear amplifying circuits.
SEE OR SEARCH CLASS:
326, Electronic Digital Logic Circuitry, appropriate
subclasses for Boolean algebra functions.
330, Amplifiers, 250 for semiconductor linear amplifiers,
per se.
341, Coded Data Generation or Conversion, 138 for nonlinear
analog to digital conversion.
708, Electrical Computers: Arithmetic Processing and
Calculating, 200 for digital computation and subclasses 801+
for analog computation.
Subclass:
335
By differentiating:
This subclass is indented under subclass 334. Subject matter
wherein the output signal is proportional to the
instantaneous rate of change of the input signal.
SEE OR SEARCH THIS CLASS, SUBCLASS:
1 for signal discriminating (e.g., comparing or selecting)
without subsequent control and particularly subclasses 14+
for signal slope comparing or selecting.
336 for signal integrating.
SEE OR SEARCH CLASS:
364, Electrical Computers and Data Processing Systems,
subclass 828 for an analog computer adapted to perform a
differentiation on an input.
Subclass:
336
By integrating:
Subject matter under 334 wherein the output signal is
proportional to a time integral function of the input
signal.
SEE OR SEARCH THIS CLASS, SUBCLASS:
14 for systems wherein the rate of change of an input signal
is detected.
100 for wave conversion or shaping systems which may include
differentiating or integrating means.
131 for systems producing a sawtooth output utilizing
integration or differentiation.
335 for input signal differentiation.
SEE OR SEARCH CLASS:
318, Electricity: Motive Power Systems, subclass 141, 456+,
609+, 621+, and 702 for a motor control network involving
differentiation or integration.
323, Electricity: Power Supply or Regulation Systems,
subclasses 212-219 for miscellaneous phase control networks
which involve differentiating or integrating networks.
331, Oscillators, subclass 17 for systems with means for the
automatic frequency control of an oscillator and involving
integrating networks.
333, Wave Transmission Lines and Networks, subclass 19 for a
passive network performing differentiation or integration and
being of general utility.
388, Electricity: Motor Control Systems, cross-reference art
collections 900+ for motor control systems including
integration circuits.
708, Electrical Computers: Arithmetic Processing and
Calculating, 823 for an analog computer adapted to perform
an integration function.
Subclass:
337
Having switched capacitance:
This subclass is indented under subclass 336. Subject matter
wherein the time integral function is determined by a
particular capacitor arrangement which is variable dependent
upon a connect/disconnect path.
SEE OR SEARCH THIS CLASS, SUBCLASS:
365 for gating of an input signal between input and output.
554 for an adjustable filter utilizing a switched capacitive
arrangement.
Subclass:
338
With thermionic tube:
This subclass is indented under subclass 336. Subject matter
including an electron tube which ejects electrons by
elevating the temperature of the tube cathode.
Subclass:
339
With summing or counting:
This subclass is indented under subclass 336. Subject matter
wherein (a) a signal is produced that represents a weighted
sum of the input signal or (b) a device is incremented or
decremented at discrete intervals upon receipt of the input
signal.
SEE OR SEARCH THIS CLASS, SUBCLASS:
361 for miscellaneous summing circuits.
Subclass:
340
Single vacuum tube:
This subclass is indented under subclass 336. Subject matter
including only one device with sealed envelope which controls
the flow of electrons between spaced electrodes through a
fully or partially evacuated space.
Subclass:
341
With compensation:
This subclass is indented under subclass 336. Subject matter
wherein an integration circuit is maintained in its normal
operating state or offsets any undesirable changes in its
circuitry.
Subclass:
342
With transducer:
This subclass is indented under subclass 336. Subject matter
including a device that converts energy forms (other than
electrical) into an electrical energy signal.
(1) Note. The other energy forms may be mechanical,
thermal, hydraulic, chemical, etc.
Subclass:
343
With rectifier circuit:
This subclass is indented under subclass 336. Subject matter
including a device that converts alternating current to
direct current.
(1) Note. A rectifier circuit may be used prior to
integrating the input signal.
Subclass:
344
Including RC circuit:
This subclass is indented under subclass 336. Subject matter
including a particular arrangement of capacitance and
resistance.
Subclass:
345
Having feedback:
This subclass is indented under subclass 336. Subject matter
wherein a portion of the output signal is returned to an
input.
(1) Note. The feedback may be used to adjust the time
constant of the time integral function.
Subclass:
346
Exponential:
This subclass is indented under subclass 334. Subject matter
wherein the output signal is proportional to an input signal
that is raised to a particular algebraic power.
SEE OR SEARCH THIS CLASS, SUBCLASS:
350 for logarithmic functions.
Subclass:
347
Square root:
This subclass is indented under subclass 346. Subject matter
wherein the output signal is proportional to the input signal
raised to the power of one half.
Subclass:
348
RMS:
This subclass is indented under subclass 347. Subject matter
wherein the output signal is proportional to the square root
of the average of the squares of the input signal taken
throughout one period.
(1) Note. For example, in a sine wave, this value is 0.707
times the peak value of the input waveform.
SEE OR SEARCH THIS CLASS, SUBCLASS:
104 for conversion of an AC signal to a corresponding DC
signal at an unloaded output.
Subclass:
349
Square function:
This subclass is indented under subclass 346. Subject matter
wherein the output signal is proportional to the input signal
raised to the power of two or a multiple of two.
SEE OR SEARCH THIS CLASS, SUBCLASS:
356 for the determination of the product of two inputs, in
general.
SEE OR SEARCH CLASS:
708, Electrical Computers: Arithmetic Processing and
Calculating, subclass 606 and 808 for the evaluation of
powers by a digital or analog electrical calculating
computer, respectively.
Subclass:
350
Logarithmic:
This subclass is indented under subclass 334. Subject matter
wherein the output signal is proportional to an inverse
exponential function of the input signal.
(1) Note. Function generators for producing internal
logarithmic functions in analog computers are found in Class
364.
SEE OR SEARCH THIS CLASS, SUBCLASS:
346 for producing exponential functions.
SEE OR SEARCH CLASS:
340, Communications: Electrical, subclass 805 for selective
visual display systems having specified waveform generators
coupled to a display.
364, Electrical Computers and Data Processing Systems,
subclass 748.5 for digital computer manipulation of operands
having a logarithmic format and subclass 857 for analog
computer generated logarithmic function signals.
Subclass:
351
With cascade network:
This subclass is indented under subclass 350. Subject matter
including an arrangement of two or more similar circuits or
stages in which an output of one circuit provides an input to
the next circuit.
(1) Note. This is also called a tandem arrangement.
Subclass:
352
With summing:
This subclass is indented under subclass 350. Subject matter
wherein an output signal is produced that represents the
algebraic sum of applied input signals.
Subclass:
353
With vacuum tube:
This subclass is indented under subclass 350. Subject matter
including a device with sealed envelope which controls the
flow of electrons between spaced electrodes through a fully
or partially evacuated space.
Subclass:
354
Absolute value:
This subclass is indented under subclass 334. Subject matter
wherein an output signal is proportional to the negative of
an input signal, if the input signal is negative, and is
proportional to an input signal, if the input signal is
positive.
(1) Note. Usually, the output to input magnitude ratio is
unity.
Subclass:
355
Combining of plural signals:
This subclass is indented under subclass 334. Subject matter
wherein the output is a resultant function of mathematically
operating on two or more input signals.
SEE OR SEARCH THIS CLASS, SUBCLASS:
3 for systems wherein the output is a function of phase
difference of plural input waves.
40 for systems wherein the output is a function of frequency
difference of plural input waves.
105 for conversion systems for synthesizing a complex wave
from a plurality of waves.
SEE OR SEARCH CLASS:
324, Electricity: Measuring and Testing, 140 for
electricity measuring and testing systems which contain
plural inputs (e.g., summation, ratio).
348, Television, 659 for television matrixing systems.
708, Electrical Computers: Arithmetic Processing and
Calculating, 670 for apparatus which performs a complete
addition.
Subclass:
356
Product:
This subclass is indented under subclass 355. Subject matter
wherein the output signal represents an analog multiplication
of plural input signals.
SEE OR SEARCH THIS CLASS, SUBCLASS:
113 for frequency control including frequency
multiplication.
178 for pulse waveform amplitude (e.g., gain) control.
306 for miscellaneous waveform amplitude (e.g., gain)
control.
SEE OR SEARCH CLASS:
708, Electrical Computers: Arithmetic Processing and
Calculating, 620 for digital computer multipliers and
subclasses 835+ for analog computer multipliers.
Subclass:
357
Quadrant:
This subclass is indented under subclass 356. Subject matter
wherein the output signal represents an analog multiplication
performed on input signals having positive or negative
polarities.
Subclass:
358
Having feedback:
This subclass is indented under subclass 356. Subject matter
wherein a portion of the output signal is returned to an
input.
Subclass:
359
Differential amplifier:
This subclass is indented under subclass 356. Subject matter
wherein a circuit amplifies only the differences between the
two input signals and suppresses the input signals when they
have identical signals.
Subclass:
360
Quotient:
This subclass is indented under subclass 355. Subject matter
wherein the output signal represents a ratio of plural input
signals.
SEE OR SEARCH CLASS:
708, Electrical Computers: Arithmetic Processing and
Calculating, 650 for digital computer dividers and subclass
844 for analog computer dividers.
Subclass:
361
Summing:
This subclass is indented under subclass 355. Subject matter
wherein an output signal is produced that represents an
algebraic sum of input signals.
Subclass:
362
With compensation:
This subclass is indented under subclass 334. Subject matter
wherein a functional circuit is maintained in its normal
operating state or offsets any undesirable changes therein.
(1) Note. Undesired changes in the circuit signals may be
due to temperature fluctuations, component structural
differences, power supply fluctuations, etc.
SEE OR SEARCH THIS CLASS, SUBCLASS:
513 for miscellaneous circuits providing temperature
compensation.
SEE OR SEARCH CLASS:
323, Electricity: Power Supply or Regulation Systems, 220,
234+, 299+, 304+, and 318+ for load controlled or regulated
systems.
Subclass:
363
Having feedback:
This subclass is indented under subclass 334. Subject matter
wherein a portion of the output signal is returned to an
input.
Subclass:
364
With vacuum tube:
This subclass is indented under subclass 334. Subject matter
including a device with a sealed envelope which controls the
flow of electrons between spaced electrodes through a fully
or partially evacuated space.
Subclass:
365
GATING (I.E., SWITCHING INPUT TO OUTPUT):
This subclass is indented under the class definition.
Subject matter wherein one signal (a controlling signal)
determines whether an input signal is transmitted without
modification to an output or is blocked therefrom.
(1) Note. The input signal may be a DC, AC, or a complex
wave in the switching operation.
(2) Note. Excluded herein are switching systems including
those which are solely mechanical or electromechanical
(either static or dynamic) and those handling high current or
voltage.
(3) Note. Switching circuits or systems peculiar to an art
device are classified with the art device. For example, a
centralized telephone switching system is classified in Class
379, subclasses 242+.
SEE OR SEARCH THIS CLASS, SUBCLASS:
124 for signal waveform generating by periodic switching
(e.g., chopping).
337 for an integrator which utilizes the switching of a
capacitive arrangement.
554 for an adjustable filter which utilizes the switching of
a capacitance into or out of the circuit.
SEE OR SEARCH CLASS:
200, Electricity: Circuit Makers and Breakers, for closing
or opening an electrical circuit.
307, Electrical Transmission or Interconnection Systems,
subclass 29 for plural loads or sources selectively
connected and subclasses 112+ for electrical transmission or
interconnection type switching systems.
335, Electricity: Magnetically Operated Switches, Magnets,
and Electromagnets, 2 for electromagnetically actuated
switches.
337, Electricity: Electrothermally or Thermally Actuated
Switches, for electric current switching devices which
operate by heating effect.
340, Communications: Electrical, appropriate subclasses for
an alarm or indicating device or system which includes a
switching operation.
361, Electricity: Electrical Systems and Devices, 139 for
an interruptor or connector which is used for the purpose of
safety and protection of a system or a device and subclasses
160+ for a solenoid or relay control circuit.
362, Illumination, subclass 802 for a position or condition
responsive switch.
363, Electric Power Conversion Systems, for a single electric
power signal being modified when transmitted from an input to
a single output load.
370, Multiplex Communications, 351 for multiplex switching.
379, Telephonic Communications, 156, 177+, 219+, 242+, 422+,
etc., for particular switching systems used in telephonic
communication.
Subclass:
366
Superconductive (e.g., cryogenic, etc.) device:
This subclass is indented under subclass 365. Subject matter
including a switching circuit which operates at a very low
temperature (e.g., 30 K) where the electrical resistance
becomes essentially zero.
(1) Note. This subclass comprises superconductive devices
which operate at a temperature less than or equal to 30 K;
Class 505 comprises superconductive devices which operate at
a temperature higher than 30 K.
SEE OR SEARCH THIS CLASS, SUBCLASS:
186 for superconductive stable state circuits,
527 for miscellaneous superconductive circuits.
SEE OR SEARCH CLASS:
326, Electronic Digital Logic Circuitry, 1 for
superconductive electronic digital logic circuits.
505, Superconductor Technology: Apparatus, Material,
Process, appropriate subclasses for superconductive devices
operated at a temperature higher than 30 K.
Subclass:
367
Josephson junction:
This subclass is indented under subclass 366. Subject matter
including an electronic fast-switching device consisting of
two superconductors separated by a thin layer of insulator
which allows a low current flow therethrough by quantum
mechanical tunneling.
SEE OR SEARCH CLASS:
326, Electronic Digital Logic Circuitry, 3 for electronic
logic using a Josephson tunneling device.
Subclass:
368
Critical current control:
This subclass is indented under subclass 366. Subject matter
wherein the switching operation depends on a value of current
that, if exceeded, may destroy the superconductivity of the
gate conductor.
Subclass:
369
External control (e.g., piezoelectric, light, etc.):
This subclass is indented under subclass 366. Subject matter
wherein the switching operation is responsive to a physical
condition, such as, mechanical stress from a piezoelectric
element or light from an optical device, etc.
SEE OR SEARCH THIS CLASS, SUBCLASS:
187 for external effect stable state circuits.
509 for miscellaneous external effect circuits.
Subclass:
370
Magnetic field control:
This subclass is indented under subclass 369. Subject matter
wherein the switching operation depends on a variation of a
controlled magnetic field.
SEE OR SEARCH THIS CLASS, SUBCLASS:
187 for an external effect stable state circuit.
510 for miscellaneous magnetic effect circuits.
Subclass:
371
Temperature control:
This subclass is indented under subclass 369. Subject matter
wherein the switching operation is responsive to a variation
of temperature.
SEE OR SEARCH THIS CLASS, SUBCLASS:
187 for an external effect stable state circuit.
512 for miscellaneous thermal effect circuits.
Subclass:
372
Inductive effect:
This subclass is indented under subclass 366. Subject matter
wherein the switching operation depends on a property of a
circuit that tends to oppose any change of current because of
a magnetic field associated with the current itself.
SEE OR SEARCH CLASS:
336, Inductor Devices, appropriate subclasses for inductive
elements, per se.
Subclass:
373
Layout:
This subclass is indented under subclass 366. Subject matter
wherein the switching circuit is represented by its physical
structure on a substrate with a detailed description of the
topological arrangement and connection of conductors and
components.
SEE OR SEARCH THIS CLASS, SUBCLASS:
564 for miscellaneous circuits reciting integrated structure
which may include layout or layout interconnections.
SEE OR SEARCH CLASS:
257, Active Solid-State Devices (e.g., Transistors,
Solid-State Diodes), appropriate subclasses for integrated
structure, per se.
326, Electronic Digital Logic Circuitry, 101 for logic
circuits utilizing significant integrated structure, layout,
or layout interconnections.
338, Resistors, subclass 32 for superconducting resistors.
505, Superconductor Technology: Apparatus, Material,
Process, appropriate subclasses for superconducting devices
or circuits operating at a temperature greater than 30 K.
Subclass:
374
Accelerating switching:
This subclass is indented under subclass 365. Subject matter
including a circuit to minimize the time delay at the turn-on
or turn-off period, therefore increasing the switching
speed.
(1) Note. Excluded from this subclass is electronic digital
logic switching acceleration (see search notes below).
SEE OR SEARCH CLASS:
326, Electronic Digital Logic Circuitry, 17 for switching
acceleration in electronic digital logic circuitry.
Subclass:
375
Saturation prevention:
This subclass is indented under subclass 374. Subject matter
including a circuit intended to avoid the concentration of
charges stored in a bipolar transistor base region, such
concentration of charges prevents the bipolar transistor from
turning on or off quickly.
Subclass:
376
Turn-on:
This subclass is indented under subclass 374. Subject matter
including a circuit intended to reduce the time interval from
the occurrence of a control input for turning on the gate to
the occurrence of a current or a signal being gated to the
output.
Subclass:
377
Turn-off:
This subclass is indented under subclass 374. Subject matter
including a circuit intended to reduce the time interval from
the occurrence of a control input for turning off the gate to
the occurrence of a current or signal being blocked at the
gate.
Subclass:
378
Compensation for variations in external physical values
(e.g., temperature, etc.):
This subclass is indented under subclass 365. Subject matter
including a circuit to offset an undesired change in the
switched signal caused by the variation of a physical
condition outside of the switching circuit, for example,
variation in temperature, etc.
SEE OR SEARCH THIS CLASS, SUBCLASS:
513 for miscellaneous temperature compensation.
Subclass:
379
Signal transmission integrity or spurious noise override:
This subclass is indented under subclass 365. Subject matter
including a circuit to maintain signal transmission without
impairment from unwanted or unintentionally generated
electrical signals.
(1) Note. Excluded herein are circuits which relate to
signal sensitivity or transmission integrity in an electronic
digital logic circuit. These are classified in Class 326.
SEE OR SEARCH THIS CLASS, SUBCLASS:
310 for transient or signal noise reduction by limiting,
clipping, or clamping.
551 for miscellaneous unwanted signal suppression.
SEE OR SEARCH CLASS:
326, Electronic Digital Logic Circuitry, 21 for signal
sensitivity or transmission integrity in electronic digital
logic circuitry.
Subclass:
380
Preventing quick rise gating current (i.e., di/dt):
This subclass is indented under subclass 379. Subject matter
including a circuit for preventing, at the beginning of the
turn-on period, an excessive current flow change at the
control terminal which could cause damage to the switching
device.
Subclass:
381
Preventing quick rise gating voltage (i.e., dv/dt):
This subclass is indented under subclass 379. Subject matter
including a circuit for preventing, at the beginning of the
turn-on period, an excessive potential change at the control
terminal which could cause damage to the switching device.
Subclass:
382
Parasitic prevention or compensation (e.g., parasitic
capacitance, etc.):
This subclass is indented under subclass 379. Subject matter
including a circuit to alleviate detrimental changes in the
switched signal caused by the presence of inherent non-ideal
circuit elements.
(1) Note. Such undesired elements can be modeled by well
known electrical elements, such as a capacitor or inductor
and are responsible for parasitic capacitance or parasitic
inductance, respectively.
(2) Note. Parasitic capacitance or parasitic inductance may
be compensated by using impedance matching.
Subclass:
383
Ensuring fully conducting state:
This subclass is indented under subclass 379. Subject matter
including a circuit for developing an essentially equal
potential at all nodes along the transmission path of the
switched signal.
(1) Note. Irregular potentials at different nodes along a
transmission path are caused by non-ideal transistors which
tend to remain in a partially conducting state.
Subclass:
384
Switch noise signal:
This subclass is indented under subclass 379. Subject matter
including a circuit which offsets an unwanted oscillation
(ringing) or a spurious spike due to a switch being turned on
or off.
Subclass:
385
Contact bounce from mechanical switch:
This subclass is indented under subclass 384. Subject matter
wherein an electromechanically induced switching noise (i.e.,
chatter) is offset.
SEE OR SEARCH CLASS:
178, Telegraphy, subclass 17, 81, and 101+ for systems
including error prevention against contact bounce signals
resulting from a key or keyboard operation.
341, Coded Data Generation or Conversion, 24 for keyboard or
keypad with contact debounce or antichatter feature.
361, Electricity: Electrical Systems and Devices,
appropriate subclasses for protection from power or voltage
surges.
Subclass:
386
With clock input:
This subclass is indented under subclass 385. Subject matter
wherein the switching circuit accepts and is responsive to a
predetermined time-related signal or a periodic signal in
addition to the control signal.
SEE OR SEARCH THIS CLASS, SUBCLASS:
291 for the generation of a clock signal.
Subclass:
387
Control signal derived from or responsive to input signal:
This subclass is indented under subclass 379. Subject matter
wherein the control signal is dependent on or generated from
a characteristic of the input signal.
(1) Note. For example, in FET switching devices, a control
signal which is responsive to the constancy or fluctuations
of an input signal would be fed to the gate electrode to
control the FET channel impedance.
Subclass:
388
Additional external control signal:
This subclass is indented under subclass 387. Subject matter
including another control signal which controls the switching
operation and which is independent of the characteristic of
the input signal and the first control signal.
Subclass:
389
Insulated gate FET (e.g., MOSFET, etc.):
This subclass is indented under subclass 379. Subject matter
wherein the circuit includes one or more unipolar transistors
characterized by having a lightly doped substrate (e.g.,
p-type material) into which two highly doped regions (e.g.,
n+ type material) are diffused for forming source/drain
regions with the area therebetween becoming the channel for
current carriers (i.e., holes or electrons) when an
electrical field is applied; a layer of insulating material
(e.g., SiO[subscrpt]2[end subscrpt]) is grown over the
channel surface for separating the channel from a control
(i.e., gate) electrode.
(1) Note. In a unipolar transistor, the source to drain
current involves only one type of charge carrier.
(2) Note. A MOSFET or Metal-oxide field-effect transistor
has a metallic gate insulated by an oxide layer from the
semiconductor channel.
Subclass:
390
With capacitive bootstrapping:
This subclass is indented under subclass 389. Subject matter
wherein the IGFET switching circuit includes discrete,
capacitive elements, or uses its inherent capacitance to
enhance its operating condition, to achieve full switching
capabilities in response to control signals.
(1) Note. Enhancement of the performance of the switching
circuit includes boosting the DC level of the control signals
for one or more semiconductor devices, as well as boosting
the attained DC levels of individual circuit nodal locations,
usually by, for example, either a feedforward/feedback
connection or a separate time-related, pulse signal coupled
via the boosting capacitor to a particular circuit location.
SEE OR SEARCH THIS CLASS, SUBCLASS:
589 for miscellaneous bootstrap circuits.
SEE OR SEARCH CLASS:
326, Electronic Digital Logic Circuitry, subclass 88 and 92
for logic bootstrap circuits.
Subclass:
391
Complementary metal-oxide semiconductor (CMOS):
This subclass is indented under subclass 389. Subject matter
including a unit of two enhancement mode metal-oxide
field-effect transistors, each having a channel of
conductivity type opposite that of the other (e.g., p-channel
vs. n-channel) and they are connected in series across the
power supply with gates linked together.
(1) Note. In the enhancement mode, a MOSFET is normally off
with zero gate voltage applied.
(2) Note. Opposite channel conductivity type, as used
above, characterizes the induced channel majority carrier
conduction (i.e., holes for p-channel and electrons for
n-channel).
Subclass:
392
Delay controlled switch (e.g., fixed, single time of delay
control, etc.):
This subclass is indented under subclass 365. Subject matter
wherein there is a recited significant time offset between
the occurrence of a gating control signal and the actual
initiation of the gating operation.
(1) Note. Time delay network systems which control the
operation of a recited specific load circuit such as a motor,
a relay, a display system, etc., are classified elsewhere.
SEE OR SEARCH THIS CLASS, SUBCLASS:
141 for signal synchronization.
231 for phase shift of an input signal which is less than
the period thereof.
261 for time delay in producing an output waveform.
SEE OR SEARCH CLASS:
318, Electricity: Motive Power Systems, 141 for automatic
generator control with time delay and subclasses 445+ for
motive power systems with time delay, per se.
323, Electricity: Power Supply or Regulation Systems, 220,
234+, 304+, and 318+ for load controlled or regulated
systems.
361, Electricity: Electrical Systems and Devices, subclass
91.3 for overvoltage protection including time delay, and
subclasses 195+ for time delay networks which control a relay
load switching operation.
388, Electricity: Motor Control Systems, cross reference art
collection 921 for running-speed control systems including a
time delay.
Subclass:
393
With variable or multiple adjustable time of delay control
(e.g., variable charge-discharge, on-delay/off-delay control,
etc.):
This subclass is indented under subclass 392. Subject matter
wherein the time offset is varied, for example, by (1)
controlling a charge/discharge device to create different
varying times, (2) changing a setting/resetting cycle, or (3)
changing the on/off time of a control element.
SEE OR SEARCH THIS CLASS, SUBCLASS:
172 for pulse width or duration control.
Subclass:
394
With field-effect device:
This subclass is indented under subclass 393. Subject matter
including a circuit having one or more devices each having a
high input impedance and low leakage, thus providing
excellent isolation between the drive signal, which is used
to switch the input signal from one part of the circuit to
another.
SEE OR SEARCH THIS CLASS, SUBCLASS:
399 for a field-effect device used in a delay controlled
switch.
581 for miscellaneous field-effect transistor circuits.
Subclass:
395
Propagation through plural delay devices or paths:
This subclass is indented under subclass 393. Subject matter
wherein the variable or adjustable delay is achieved by
connecting the input signal to multiple delaying elements or
circuit branches.
SEE OR SEARCH THIS CLASS, SUBCLASS:
400 for a delay controlled switch having propagation through
plural delay devices or paths, in general.
Subclass:
396
With plural switching elements (e.g., sequential, etc.):
This subclass is indented under subclass 393. Subject matter
wherein multiple gating devices are utilized.
SEE OR SEARCH THIS CLASS, SUBCLASS:
269 for a plurality of time delay intervals in multiple
outputs.
401 for time delay switching using plural switching elements
in a non-variable or non-multiple adjustable time of delay.
403 for switching parallel controlled paths without any
delay of the input.
415 for applying a single input to plural outputs without
any delay of the input.
SEE OR SEARCH CLASS:
361, Electricity: Electrical Systems and Devices, 166 for
timely operated plural relays.
Subclass:
397
Including negative resistance device in delay circuit(e.g.,
unijunction transistor, etc.):
This subclass is indented under subclass 393. Subject matter
wherein the plot of the current-voltage operating
characteristics of an incorporated device has a portion with
a negative slope.
SEE OR SEARCH THIS CLASS, SUBCLASS:
498 for two electrode solid-state negative resistance gating
circuits.
568 for miscellaneous solid-state negative resistance device
circuits.
Subclass:
398
For predetermined time period:
This subclass is indented under subclass 392. Subject matter
wherein the activation duration of the switch is fixed prior
to such activation.
SEE OR SEARCH THIS CLASS, SUBCLASS:
172 for pulse waveform duration control.
Subclass:
399
With field-effect device:
This subclass is indented under subclass 392. Subject matter
including a circuit having one or more devices each having a
high input impedance and low leakage, thus providing
excellent isolation between the drive signal which is used to
switch the input signal from one part of the circuit to
another.
SEE OR SEARCH THIS CLASS, SUBCLASS:
394 for a variable or multiple adjustable time of delay
control.
581 for miscellaneous field-effect transistor circuits.
Subclass:
400
Propagation through plural delay devices or paths:
This subclass is indented under subclass 392. Subject matter
wherein the delay is controlled by connecting the input
signal to multiple delaying elements or circuit branches.
SEE OR SEARCH THIS CLASS, SUBCLASS:
395 for a delay controlled switch having a variable or
multiple adjustable delay including propagation through
plural delay devices or paths.
Subclass:
401
With plural switching elements (e.g., sequential, etc.):
This subclass is indented under subclass 392. Subject matter
wherein multiple gating devices are utilized.
SEE OR SEARCH THIS CLASS, SUBCLASS:
269 for a plurality of time delay intervals in multiple
outputs.
396 for variable or multiple adjustable time delay using
plural switching elements.
403 for switching parallel controlled paths without any
delay of the input.
415 for applying a single input to plural outputs without
any delay of the input.
SEE OR SEARCH CLASS:
361, Electricity: Electrical Systems and Devices, 166 for
timely operated plural relays.
Subclass:
402
Including negative resistance device in delay circuit (e.g.,
unijunction transistor, etc.):
This subclass is indented under subclass 392. Subject matter
wherein a plot of the current-voltage operating
characteristics of an incorporated device has a portion with
a negative slope.
SEE OR SEARCH THIS CLASS, SUBCLASS:
498 for two electrode solid-state negative resistance gating
circuits.
568 for miscellaneous negative resistance device circuits.
Subclass:
403
Parallel controlled paths:
This subclass is indented under subclass 365. Subject matter
comprising at least two signal paths having a common input
and a common output, each signal path having at least one
switch.
SEE OR SEARCH THIS CLASS, SUBCLASS:
407 for converging plural inputs with single output.
415 for diverging paths with a single input and plural
outputs.
Subclass:
404
Field-effect transistor:
This subclass is indented under subclass 403. Subject matter
wherein at least one path includes a unipolar transistor in
which current carriers are injected at a source terminal and
passed to a drain terminal through a channel of semiconductor
material whose conductivity depends largely on an electrical
field applied to the semiconductor from a control electrode
(i.e., gate).
(1) Note. In a unipolar transistor, the source to drain
current involves only one type of charge carrier (i.e., holes
in a p-type material channel and electrons in an n-type
material channel).
(2) Note. Two types of FET structures are prevalent: (a)
an all-junction device, known as a junction FET or JFET
characterized by having heavily doped impurity regions of one
type (e.g., p-type material), known as gate regions, on both
sides of a second type semiconductor bar (e.g., n+ type
material) to form a pn junction, and (b) a device such as a
MOSFET/IGFET, consisting of a lightly doped substrate (e.g.,
p-type material) into which two highly doped regions (e.g.,
n+ type material) are diffused for forming source/drain
regions with the area therebetween becoming the channel for
current carriers (i.e., holes or electrons) and with a layer
of insulating material (e.g., SiO[subscrpt]2[end subscrpt])
grown over the channel surface for separating the channel
from a control (i.e., gate) electrode.
Subclass:
405
Bipolar transistor:
This subclass is indented under subclass 403. Subject matter
wherein at least one path includes a three or more electrode
semiconductor device of the type having at least two
potential barriers and having a controlled current flow of
both majority and minority carriers (i.e., holes and
electrons).
(1) Note. Npn and pnp type transistors are conventional
bipolar transistors; each has three regions, three electrodes
and two junctions. Each of the three regions is connected
externally by a terminal labeled emitter, base, or
collector.
Subclass:
406
Electron tube:
This subclass is indented under subclass 403. Subject matter
wherein at least one path includes a vacuum tube or a gas
filled tube, in which electrical currents flow between spaced
electrodes, and in which the conduction of charged particles
(e.g., electrons or ions), takes place between these
electrodes.
Subclass:
407
Converging with plural inputs and single output:
This subclass is indented under subclass 365. Subject matter
comprising at least two signal paths having separate inputs
and a common output, each signal path having at least one
switch.
SEE OR SEARCH THIS CLASS, SUBCLASS:
403 for controlled parallel paths.
415 for diverging paths with a single input and plural
outputs.
SEE OR SEARCH CLASS:
370, Multiplex Communications, appropriate subclasses for
information multiplexing.
Subclass:
408
Field-effect transistor:
This subclass is indented under subclass 407. Subject matter
wherein at least one path includes a unipolar transistor in
which current carriers are injected at a source terminal and
pass to a drain terminal through a channel of semiconductor
material whose conductivity depends largely on an electrical
field applied to the semiconductor from a control electrode
(gate).
(1) Note. In a unipolar transistor, the source to drain
current involves only one type of charge carrier (i.e., holes
in a p-type material channel and electrons in an n-type
material channel).
(2) Note. Two types of FET structures are prevalent: (a)
an all-junction device, known as a junction FET or JFET
characterized by having heavily doped impurity regions of one
type (e.g., p-type material), known as gate regions, on both
sides of a second type semiconductor bar (e.g., n+ type
material) to form a pn junction, and (b) a device such as a
MOSFET/IGFET, consisting of a lightly doped substrate (e.g.,
p-type material) into which two highly doped regions (e.g.,
n+ type material) are diffused for forming source/drain
regions with the area therebetween becoming the channel for
current carriers (i.e., holes or electrons) and with a layer
of insulating material (e.g., SiO[subscrpt]2[end subscrpt])
grown over the channel surface for separating the channel
from a control (i.e., gate) electrode.
Subclass:
409
Push-pull circuit:
This subclass is indented under subclass 408. Subject matter
wherein the switching circuit includes two similar
field-effect transistors connected in series, having two
input terminals and a common output terminal, and
alternatively transmitting input signals to the output.
Subclass:
410
With complementary transistor devices:
This subclass is indented under subclass 409. Subject matter
wherein the push-pull circuit includes two field-effect
transistors of n-type channel and p-type channel connected in
series.
Subclass:
411
Bipolar transistor:
This subclass is indented under subclass 407. Subject matter
wherein at least one path includes a three or more electrode
semiconductor device of the type having at least two
potential barriers and having a controlled current flow of
both majority and minority carriers (i.e., holes and
electrons).
(1) Note. Npn and pnp type transistors are conventional
bipolar transistors, each has three regions, three
electrodes, and two junctions. Each of the three regions is
connected externally by a terminal labeled emitter, base, or
collector.
Subclass:
412
Push-pull circuit:
This subclass is indented under subclass 411. Subject matter
including a circuit containing two similar bipolar
transistors connected in series, having two input terminals
and a common output terminal, and alternatively transmitting
input signals to the output.
Subclass:
413
With complementary transistor devices:
This subclass is indented under subclass 412. Subject matter
including two bipolar transistors of opposite conductivity
type connected in series (e.g., npn and pnp transistors).
Subclass:
414
Electron tube:
This subclass is indented under subclass 407. Subject matter
wherein at least one path includes a vacuum tube or a gas
filled device, in which electrical currents flow between
spaced electrodes and in which the conduction of charged
particles (e.g., electrons) takes place between electrodes.
Subclass:
415
Diverging with single input and plural outputs:
This subclass is indented under subclass 365. Subject matter
comprising at least two signal paths having a single input
and separate outputs, each signal path containing at least
one switch.
SEE OR SEARCH THIS CLASS, SUBCLASS:
403 for controlled parallel paths.
407 for converging paths with plural inputs and single
output.
SEE OR SEARCH CLASS:
370, Multiplex Communications, appropriate subclasses for
information multiplexing.
Subclass:
416
Field-effect transistor:
This subclass is indented under subclass 415. Subject matter
wherein at least one path includes a unipolar transistor in
which current carriers are injected at a source terminal and
passed to a drain terminal through a channel of semiconductor
material whose conductivity depends largely on an electrical
field applied to the semiconductor from a control electrode
(i.e., gate).
(1) Note. In a unipolar transistor, the source to drain
current involves only one type of charge carrier (i.e., holes
in a p-type material channel and electrons in an n-type
material channel).
(2) Note. Two types of FET structures are prevalent: (a)
an all-junction device, known as a junction FET or JFET
characterized by having heavily doped impurity regions of one
type (e.g., p-type material), known as gate regions, on both
sides of a second type semiconductor bar (e.g., n+ type
material) to form a pn junction, and (b) a device such as a
MOSFET/IGFET, consisting of a lightly doped substrate (e.g.,
p-type material) into which two highly doped regions (e.g.,
n+ type material) are diffused for forming source/drain
regions with the area therebetween becoming the channel for
current carriers (i.e., holes or electrons) and with a layer
of insulating material (e.g., SiO[subscrpt]2[end subscrpt])
grown over the channel surface for separating the channel
from a control (i.e., gate) electrode.
Subclass:
417
Bipolar transistor:
This subclass is indented under subclass 415. Subject matter
wherein at least one path includes a three or more electrode
semiconductor device of the type having at least two
potential barriers and having a controlled current flow of
both majority and minority carriers (i.e., holes and
electrons).
(1) Note. Npn and pnp type transistors are conventional
bipolar transistors which have three regions, three
electrodes and two junctions. Each of the three regions is
connected externally by a terminal labeled emitter, base, or
collector.
Subclass:
418
Electron tube:
This subclass is indented under subclass 415. Subject matter
wherein at least one path includes a vacuum tube or gas
filled device, in which electrical currents flow between
spaced electrodes and in which the conduction of charged
particles (e.g., electrons) takes place between electrodes.
Subclass:
419
Utilizing three or more electrode solid-state device:
This subclass is indented under subclass 365. Subject matter
including a semiconductor device containing three or more
elements that perform one or more of the following: (a) emit
or collect electrons or holes, or (b) control the electron or
hole movements by an applied electrical field.
Subclass:
420
Breakdown characteristic (e.g., punch-through, tunneling,
etc.):
This subclass is indented under subclass 419. Subject matter
wherein the operation of the solid-state device is
characterized by a sudden change from high dynamic electrical
resistance to a very low dynamic resistance in a reverse
biased semiconductor devices (e.g., a reverse biased junction
between p-type and n-type semiconductor materials), wherein
reverse current increases rapidly for a small increase in
reverse applied voltage, and the device behaves as if it had
negative electrical resistance.
(1) Note. Examples of breakdown characteristic are
punch-through or tunneling. In punch-through, two adjacent
diffused transistor regions become shorted together, causing
a sharp rise in current. In tunneling, particles under
certain conditions have the ability to pass through a barrier
that normally it cannot pass over because of a required
energy level.
SEE OR SEARCH THIS CLASS, SUBCLASS:
580 for miscellaneous circuits with breakdown transistor
devices.
584 for miscellaneous circuits with breakdown diodes.
Subclass:
421
Zener:
This subclass is indented under subclass 420. Subject matter
wherein a breakdown is caused in a semiconductor device by
the field emission of charge carriers in a depletion layer.
SEE OR SEARCH THIS CLASS, SUBCLASS:
584 for miscellaneous circuits with breakdown diodes.
Subclass:
422
Avalanche:
This subclass is indented under subclass 420. Subject matter
wherein a breakdown is caused by the action of a strong
electric field which causes some free carriers to gain
enough energy to liberate new hole-electron pairs by
ionization.
SEE OR SEARCH THIS CLASS, SUBCLASS:
584 for miscellaneous circuits with breakdown diodes.
Subclass:
423
Bridge circuit:
This subclass is indented under subclass 419. Subject matter
including four or more solid-state devices with their input
and output terminals connected in a closed loop to form a
four arm network, and at least one solid-state device is a
transistor.
SEE OR SEARCH THIS CLASS, SUBCLASS:
588 for miscellaneous bridge circuits.
Subclass:
424
Field-effect transistor:
This subclass is indented under subclass 423. Subject matter
wherein at least one arm of the bridge circuit includes a
unipolar transistor in which current carriers are injected at
a source terminal and pass to a drain terminal through a
channel of semiconductor material whose conductivity depends
largely on an electrical field applied to the semiconductor
from a control electrode (i.e., gate).
(1) Note. In a unipolar transistor, the source to drain
current involves only one type of charge carrier (i.e., holes
in a p-type material channel and electrons in an n-type
material channel).
(2) Note. Two types of FET structures are prevalent: (a)
an all-junction device, known as a junction FET or JFET
characterized by having heavily doped impurity regions of one
type (e.g., p-type material), known as gate regions, on both
sides of a second type semiconductor bar (e.g., n+ type
material) to form a pn junction, and (b) a device such as a
MOSFET/IGFET, consisting of a lightly doped substrate (e.g.,
p-type material) into which two highly doped regions (e.g.,
n+ type material) are diffused for forming source/drain
regions with the area therebetween becoming the channel for
current carriers (i.e., holes or electrons) and with a layer
of insulating material (e.g., SiO[subscrpt]2[end subscrpt])
grown over the channel surface for separating the channel
from a control (i.e., gate) electrode.
Subclass:
425
Bilateral transistor:
This subclass is indented under subclass 419. Subject matter
wherein the solid-state device is a transistor which conducts
equally in either direction.
Subclass:
426
Plural:
This subclass is indented under subclass 425. Subject matter
wherein the switch comprises more than one bilateral
transistor.
Subclass:
427
Field-effect transistor:
This subclass is indented under subclass 419. Subject matter
including a unipolar transistor in which current carriers are
injected at a source terminal and pass to a drain terminal
through a channel of semiconductor material whose
conductivity depends largely on an electrical field applied
to the semiconductor from a control electrode (gate).
(1) Note. In a unipolar transistor, the source to drain
current involves only one type of charge carrier (i.e., holes
in a p-type material channel and electrons in an n-type
material channel).
(2) Note. Two types of FET structures are prevalent: (a)
an all-junction device, known as a junction FET or JFET
characterized by having heavily doped impurity regions of one
type (e.g., p-type material), known as gate regions, on both
sides of a second type semiconductor bar (e.g., n+ type
material) to form a pn junction, and (b) a device such as a
MOSFET/IGFET, consisting of a lightly doped substrate (e.g.,
p-type material) into which two highly doped regions (e.g.,
n+ type material) are diffused for forming source/drain
regions with the area therebetween becoming the channel for
current carriers (i.e., holes or electrons) and with a layer
of insulating material (e.g., SiO[subscrpt]2[end subscrpt])
grown over the channel surface for separating the channel
from a control (i.e., gate) electrode.
Subclass:
428
With silicon controlled rectifier (SCR):
This subclass is indented under subclass 427. Subject matter
wherein the switching circuit includes a field-effect
transistor and a four layer (pnpn), three junction, three
electrode (anode, cathode, and gate) device which can be
triggered into conduction in only one direction.
Subclass:
429
Four or more electrode solid-state device:
This subclass is indented under subclass 427. Subject matter
including a semiconductor device containing four or more
elements that emit or collect electrons or holes, or that
control their movements by an applied electrical field.
Subclass:
430
JFET (i.e., junction field-effect transistor):
This subclass is indented under subclass 427. Subject matter
including a field-effect transistor characterized by having
heavily doped impurity regions of one type material (e.g.,
p-type), known as gate regions on both sides of a second type
material semiconductor bar (e.g., n+ type) to form a pn
junction.
Subclass:
431
MESFET (i.e., metal semiconductor field-effect transistor):
This subclass is indented under subclass 430. Subject matter
wherein the junction field-effect transistor operates on the
principle of the injection of very highly concentrated
majority carriers across a potential difference barrier which
is formed by the junction of a lightly doped semiconductor
substrate and a metal layer deposited thereon (i.e., Schottky
gate junction).
(1) Note. A MESFET can utilize a semiconductor device type
silicon or gallium arsenide material; however, GaAs is most
frequently used.
Subclass:
432
With bipolar transistor:
This subclass is indented under subclass 427. Subject matter
including a field-effect transistor and a semiconductor
device of the type having at least two potential barriers and
having a controlled current flow of both majority and
minority carriers (i.e., holes and electrons).
Subclass:
433
Bi-CMOS:
This subclass is indented under subclass 432. Subject matter
including a bipolar transistor and a unit of two enhancement
mode metal-oxide field-effect transistors connected in series
with their gates linked together, each field-effect
transistor has a channel of conductivity type opposite that
of the other (e.g., p-channel vs. n-channel).
Subclass:
434
Insulated gate FET (e.g., MOSFET, etc.):
This subclass is indented under subclass 427. Subject matter
including a unipolar transistor characterized by having a
lightly doped substrate (e.g., p-type material) into which
two highly doped regions (e.g., n+ type material) are
diffused for forming source/drain regions with the area
therebetween becoming the channel for current carriers (i.e.,
holes or electrons) when an electrical field is applied and a
layer of insulating material (e.g., SiO[subscrpt]2[end
subscrpt]) is grown over the channel surface for separating
the channel from a control (i.e., gate) electrode.
(1) Note. In a unipolar transistor, the source to drain
current involves only one type of charge carrier.
(2) Note. A MOSFET or Metal-oxide field-effect transistor
has a metallic gate insulated by an oxide layer from the
semiconductor channel.
Subclass:
435
GaAs:
This subclass is indented under subclass 434. Subject matter
wherein the semiconductor material is gallium arsenide.
Subclass:
436
Plural devices in series:
This subclass is indented under subclass 434. Subject matter
having more than one insulated gate FET successively
connected together.
Subclass:
437
Complementary metal-oxide semiconductor (CMOS):
This subclass is indented under subclass 434. Subject matter
wherein the switching device includes a unit of two
enhancement mode metal-oxide field-effect transistors, each
having a channel of conductivity type opposite that of the
other (e.g., p-channel vs. n-channel) and they are connected
in series across the power supply with gates linked
together.
(1) Note. In the enhancement mode, a MOSFET is normally off
with zero gate voltage applied.
(2) Note. Opposite channel conductivity type, as used
above, characterizes the induced channel majority carrier
conduction (i.e., holes for p-channel and electrons for
n-channel).
Subclass:
438
Four or more layer device (e.g., thyristor, etc.):
This subclass is indented under subclass 419. Subject matter
including a semiconductor device with four or more
alternating layers of p-type and n-type material, (e.g.,
pnpn, etc.)
(1) Note. A typical four layer device is a thyristor which
is a device comprising three or more junctions, at least one
of the junctions can switch between reverse- and
forward-voltage polarity within a single quadrant of the
anode-to-cathode voltage-current characteristics.
Subclass:
439
Bipolar transistor circuit configuring SCR device:
This subclass is indented under subclass 438. Subject matter
wherein a circuit built with bipolar transistors performs the
same function as a silicon controlled rectifier.
Subclass:
440
GTO (i.e., gate turnoff):
This subclass is indented under subclass 438. Subject matter
including a four layer pnpn device similar in construction to
an SCR, but which is switched into a nonconduction state by a
polarity reverse signal applied to the gate or control
electrode.
Subclass:
441
Plural or combined with other four or more layer device:
This subclass is indented under subclass 440. Subject matter
having more than one gate turnoff device or having at least
one GTO and another four or more layer device.
Subclass:
442
Separate ON and OFF control circuit:
This subclass is indented under subclass 440. Subject matter
wherein distinct circuits are used to control the turn-on and
turn-off of the switching circuit.
Subclass:
443
Transformer or inductor in control circuit:
This subclass is indented under subclass 440. Subject matter
wherein the control circuit includes a device which opposes
any change of current therethrough because of a resultant
magnetic field.
SEE OR SEARCH THIS CLASS, SUBCLASS:
190 for a stable state circuit utilizing a transformer.
SEE OR SEARCH CLASS:
336, Inductor Devices, appropriate devices for inductive
elements, per se.
Subclass:
444
Complex wave supply:
This subclass is indented under subclass 438. Subject matter
wherein the switching device's power supply has a waveform
which is a periodic wave either made up of a combination of
several frequencies or several sine waves superimposed on one
another.
Subclass:
445
Silicon controlled rectifier (SCR):
This subclass is indented under subclass 444. Subject matter
including a four layer, three junction device, which can be
triggered into conduction in only one direction.
(1) Note. The formal name of an SCR is a "reverse-blocking
triode thyristor".
(2) Note. The three SCR terminals are called anode,
cathode, and gate.
Subclass:
446
Triac:
This subclass is indented under subclass 445. Subject matter
including a bidirectional rectifier (essentially two SCRs in
parallel) that functions as an electronically controlled
switch for AC loads and having an npnpn structure that can be
triggered into either forward or reverse conduction (i.e.,
transmits AC power across its anode-cathode) by a pulse
applied to its gate electrode.
Subclass:
447
AC supply:
This subclass is indented under subclass 438. Subject matter
wherein the switching circuit is power supplied by a voltage
source whose polarity changes, or alternates, with time.
Subclass:
448
Device in bridge:
This subclass is indented under subclass 447. Subject matter
including four or more solid-state devices with their input
and output terminals connected in a closed loop to form a
four arm network, which may include another arm, called a
diagonal arm, connected across two adjacent arms of the
network between an input terminal and an output terminal and
at least one solid-state device has four or more
semiconducting layers.
SEE OR SEARCH THIS CLASS, SUBCLASS:
588 for miscellaneous bridge circuits.
Subclass:
449
PUT (i.e., programmable unijunction transistor):
This subclass is indented under subclass 447. Subject matter
including a thyristor with an anode gate in which the
anode-gate voltage differential determines the conduction or
nonconduction state of the device.
SEE OR SEARCH THIS CLASS, SUBCLASS:
569 for miscellaneous unijunction transistor circuits.
Subclass:
450
Four electrodes:
This subclass is indented under subclass 447. Subject matter
including a four or more layer device which has four
terminals permitting connection to external circuits.
Subclass:
451
Zero point switching:
This subclass is indented under subclass 447. Subject matter
wherein the switching device is switched or forward-biased to
allow conduction of the AC power through the device's
anode-cathode region at the point in time of the AC operating
cycle when the AC waveform crosses the zero voltage level
(i.e., moving from the negative part of the phase to the
positive part of the operating phase or vice-versa).
SEE OR SEARCH THIS CLASS, SUBCLASS:
78 for amplitude reference crossover detecting and
particularly subclasses 79 for amplitude detecting of zero
crossover without subsequent control.
Subclass:
452
With triac:
This subclass is indented under subclass 451. Subject matter
including a bidirectional rectifier (essentially two SCRs in
parallel) that functions as an electronically controlled
switch for AC loads and having an npnpn structure that can be
triggered into either forward or reverse conduction (i.e.,
transmits AC power across its anode-cathode) by a pulse
applied to its gate electrode.
Subclass:
453
Silicon controlled rectifier (SCR):
This subclass is indented under subclass 447. Subject matter
including a four layer, three junction device, which can be
triggered into conduction in only one direction.
(1) Note. The formal name of an SCR is a "reverse-blocking
triode thyristor".
(2) Note. The three SCR terminals are called anode,
cathode, and gate.
Subclass:
454
With unijunction transistor:
This subclass is indented under subclass 453. Subject matter
wherein the switching circuit includes a silicon controlled
rectifier combined with a three-terminal semiconductor having
only one pn junction and exhibiting a stable open-circuit
negative resistance property.
SEE OR SEARCH THIS CLASS, SUBCLASS:
569 for miscellaneous unijunction transistor circuits.
Subclass:
455
Triac:
This subclass is indented under subclass 453. Subject matter
including a bidirectional rectifier (essentially two SCRs in
parallel) that functions as an electronically controlled
switch for AC loads and having an npnpn structure that can be
triggered into either forward or reverse conduction (i.e.,
transmits AC power across its anode-cathode) by a pulse
applied to its gate electrode.
Subclass:
456
Plural:
This subclass is indented under subclass 455. Subject matter
including more than one triac.
Subclass:
457
Combined with diac:
This subclass is indented under subclass 455. Subject matter
including a triac and a three layer (npn), two terminal
switching semiconductor device.
(1) Note. A diac is also called a three layer diode, a
two-lead alternating current switching semiconductor, or a
two-terminal voltage controlled device which exhibits a
bilateral negative resistance characteristic.
Subclass:
458
Combined with diverse four or more layer device:
This subclass is indented under subclass 455. Subject matter
including a triac and at least one different four or more
layer device.
Subclass:
459
With bipolar transistor:
This subclass is indented under subclass 455. Subject matter
including a triac and a transistor of the type having at
least two potential barriers and having a controlled current
flow of both majority and minority carriers (i.e., holes and
electrons).
Subclass:
460
Plural SCRs:
This subclass is indented under subclass 453. Subject matter
wherein more than one silicon controlled rectifier device is
connected along the AC power supply path.
Subclass:
461
Inverse parallel connection:
This subclass is indented under subclass 460. Subject matter
wherein two four or more layer devices are connected across
each other, but in opposite directions (i.e., the cathode of
one device is joined to the anode of the other device at one
common node and vice versa at the other common node).
Subclass:
462
With bipolar transistor:
This subclass is indented under subclass 461. Subject matter
wherein the switching circuit includes plural silicon
controlled rectifiers and a transistor of the type having at
least two potential barriers and having a controlled current
flow of both majority and minority carriers (i.e., holes and
electrons).
Subclass:
463
With bipolar transistor:
This subclass is indented under subclass 453. Subject matter
wherein the switching circuit includes a silicon controlled
rectifier and a transistor of the type having at least two
potential barriers and having a controlled current flow of
both majority and minority carriers (i.e., holes and
electrons).
Subclass:
464
Having plural four or more layer devices:
This subclass is indented under subclass 447. Subject matter
wherein more than one four or more layer device is connected
along the AC power supply path.
Subclass:
465
DC supply:
This subclass is indented under subclass 438. Subject matter
wherein the switching circuit is power supplied by a steady
voltage source (i.e., its positive and negative terminals do
not change their potentials over time).
Subclass:
466
PUT (i.e., programmable unijunction transistor):
This subclass is indented under subclass 465. Subject matter
including a thyristor with an anode gate in which the
anode-gate voltage differential determines the conduction or
nonconduction state of the device.
Subclass:
467
Four electrodes:
This subclass is indented under subclass 465. Subject matter
including a four or more layer device which has four
terminals for connection to external circuits.
Subclass:
468
SCR and unijunction transistor:
This subclass is indented under subclass 465. Subject matter
wherein the switching circuit includes a silicon controlled
rectifier combined with a three-terminal semiconductor having
only one pn junction and exhibiting a stable open circuit
negative resistance property.
Subclass:
469
Triac:
This subclass is indented under subclass 465. Subject matter
including a bidirectional rectifier (essentially two SCRs in
parallel) that functions as an electronically controlled
switch and having an npnpn structure that can be triggered
into either forward or reverse conduction by a pulse applied
to its gate electrode.
Subclass:
470
Plural devices:
This subclass is indented under subclass 465. Subject matter
wherein more than one four or more layer device is connected
along the DC power supply path.
Subclass:
471
Series anode-cathode connection:
This subclass is indented under subclass 470. Subject matter
wherein a plurality of four or more layer devices are
successively connected, the positive terminal (anode) of one
device is joined to the negative terminal (cathode) of the
immediate adjacent device (i.e., cascade connected).
Subclass:
472
Plural paths:
This subclass is indented under subclass 471. Subject matter
having more than one string of series connections.
Subclass:
473
Parallel connection:
This subclass is indented under subclass 470. Subject matter
wherein a plurality of four or more layer devices are
connected such that all positive terminals (anodes) are
joined to a common node and all negative terminals (cathodes)
are joined to another common node.
Subclass:
474
With bipolar transistor:
This subclass is indented under subclass 470. Subject matter
having more than one four or more layer device combined with
a transistor of the type having at least two potential
barriers and having a controlled current flow of both
majority and minority carriers (i.e., holes and electrons).
Subclass:
475
SCR and bipolar transistor:
This subclass is indented under subclass 465. Subject matter
wherein the switching circuit includes a silicon controlled
rectifier and a transistor of the type having at least two
potential barriers and having a controlled current flow of
both majority and minority carriers (i.e., holes and
electrons).
Subclass:
476
Triac:
This subclass is indented under subclass 438. Subject matter
including a bidirectional rectifier (essentially two SCRs in
parallel) that functions as an electronically controlled
switch and having an npnpn structure that can be triggered
into either forward or reverse conduction by a pulse applied
to its gate electrode.
Subclass:
477
Unijunction transistor (UJT):
This subclass is indented under subclass 419. Subject matter
including a three terminal semiconductor having only one pn
junction and exhibiting a stable open-circuit negative
resistance property.
SEE OR SEARCH THIS CLASS, SUBCLASS:
569 for miscellaneous unijunction transistor circuits.
Subclass:
478
Bipolar transistor:
This subclass is indented under subclass 419. Subject matter
including a semiconductor device of the type having at least
two potential barriers and having a controlled current flow
of both majority and minority carriers (i.e., holes and
electrons).
(1) Note. Npn and pnp type transistors are conventional
bipolar transistors which have three regions, three
electrodes, and two junctions. Each of the three regions is
connected externally by a terminal labeled emitter, base, or
collector.
Subclass:
479
Special four or more electrode device (e.g., multiple bases,
three electrode bipolar with FET gate, etc.):
This subclass is indented under subclass 478. Subject matter
wherein the bipolar transistor has more than three electrodes
or has particular features, such as an additional FET gate.
Subclass:
480
Multiple emitter transistor:
This subclass is indented under subclass 479. Subject matter
wherein the bipolar transistor has at least two emitter
regions in addition to the base and collector regions.
Subclass:
481
Multiple collector transistor:
This subclass is indented under subclass 479. Subject matter
wherein the bipolar transistor has at least two collector
regions in addition to the base and emitter regions.
Subclass:
482
Plural:
This subclass is indented under subclass 478. Subject matter
having more than one bipolar transistor.
Subclass:
483
Darlington connection:
This subclass is indented under subclass 482. Subject matter
which includes a circuit of two similar transistors where
their collectors are tied together and the emitter of the
first transistor is directly coupled to the base of the
second transistor such that the emitter current of the first
transistor equals the base current of the second transistor.
(1) Note. A Darlington connection is also called a
Darlington pair, double emitter follower, or
beta-multiplier.
Subclass:
484
Opposite conductivity (i.e., complementary):
This subclass is indented under subclass 482. Subject matter
wherein transistors of the npn and pnp type are present in
the same circuit.
SEE OR SEARCH THIS CLASS, SUBCLASS:
576 for miscellaneous complementary transistor circuits.
Subclass:
485
Control circuit in cascade:
This subclass is indented under subclass 484. Subject matter
wherein the switching control circuit includes two similar
transistors arranged in tandem, with the output of one
connected to the input of the next.
SEE OR SEARCH THIS CLASS, SUBCLASS:
483 for a bipolar Darlington connected gating circuit.
Subclass:
486
Control circuit in totem pole:
This subclass is indented under subclass 484. Subject matter
wherein the switching control circuit includes two similar
transistors arranged in a push-pull circuit which
alternatively operate to provide a single ended control
output signal.
Subclass:
487
Control circuit in cascade:
This subclass is indented under subclass 482. Subject matter
wherein the switching control circuit includes two similar
transistors arranged in tandem, with the output of one
connected to the input of the next.
SEE OR SEARCH THIS CLASS, SUBCLASS:
483 for a bipolar Darlington connected gating circuit.
Subclass:
488
Control circuit in totem pole:
This subclass is indented under subclass 482. Subject matter
wherein the switching control circuit includes two similar
transistors arranged in a push-pull circuit which
alternatively operate to provide a single ended control
output signal.
Subclass:
489
Control circuit with common emitter:
This subclass is indented under subclass 482. Subject matter
wherein the switching control circuit includes a bipolar
transistor with the emitter terminal connected to a common
ground of the circuit, and the outputs at the collector
terminal provide control voltages to the switch.
Subclass:
490
With current mirror:
This subclass is indented under subclass 489. Subject matter
wherein the control circuit relies on the collector current
matching of two transistors when connected together base to
base and emitter to emitter with one transistor having its
collector connected to its base.
(1) Note. The collector currents are matched by having a
predetermined ratio relationship to each other. When one of
the collector current changes, the other also changes to keep
the ratio relationship constant.
SEE OR SEARCH CLASS:
323, Electricity: Power Supply or Regulation Systems,
subclass 315 for a current regulator using a current
mirror.
Subclass:
491
With emitter follower:
This subclass is indented under subclass 489. Subject matter
wherein the control circuit has a transistor amplifier
circuit configuration which is characterized by relatively
high input impedance, low output impedance, and a voltage
gain of less than unity.
Subclass:
492
Control circuit with common collector:
This subclass is indented under subclass 482. Subject matter
wherein the switching control circuit includes a bipolar
transistor with the collector terminal connected to a common
ground of the circuit, and the outputs at the emitter
terminal provide control voltages to the switch.
Subclass:
493
Utilizing two electrode solid-state device:
This subclass is indented under subclass 365. Subject matter
including a semiconductor device containing two elements that
emit or collect electrons or holes, or that control their
movements by an applied electrical field.
SEE OR SEARCH THIS CLASS, SUBCLASS:
583 for miscellaneous two electrode solid-state device
circuits.
Subclass:
494
Bridge circuit:
This subclass is indented under subclass 493. Subject matter
including four two-electrode solid-state devices with their
input and output terminals connected in a closed loop to form
a four arm network.
(1) Note. A bridge circuit may have another arm, called the
diagonal arm, which is connected across two adjacent arms of
the network between an input terminal and an output
terminal.
SEE OR SEARCH THIS CLASS, SUBCLASS:
588 for miscellaneous bridge circuits.
Subclass:
495
Combined with diverse device in at least one arm:
This subclass is indented under subclass 494. Subject matter
wherein a two-electrode solid-state device is combined with
another device of a different type in at least one of the
bridge arms.
Subclass:
496
Plural:
This subclass is indented under subclass 494. Subject matter
including more than one bridge circuit.
Subclass:
497
Active element in diagonal arm:
This subclass is indented under subclass 494. Subject matter
wherein the bridge circuit has in its diagonal arm a specific
device that requires power for functioning.
Subclass:
498
Negative resistance:
This subclass is indented under subclass 493. Subject matter
wherein the switch comprises a solid-state two electrode
device whose characteristic on a current-voltage plot has a
portion with a negative slope.
SEE OR SEARCH THIS CLASS, SUBCLASS:
568 for miscellaneous negative resistance device circuits.
Subclass:
499
"N"-shape curve on I-V plot (e.g., tunnel diode type, etc.):
This subclass is indented under subclass 498. Subject matter
including a solid-state device whose characteristic on a
current versus voltage plot (i.e., with the current plotted
on the Y axis and voltage on the X axis) has an "N"-shape.
SEE OR SEARCH THIS CLASS, SUBCLASS:
195 for a stable state circuit utilizing an "N"-shape
negative resistance diode.
Subclass:
500
"S"-shape curve on I-V plot (e.g., pnpn diode type, etc.):
This subclass is indented under subclass 498. Subject matter
including a solid-state device whose characteristic on a
current versus voltage plot (i.e., with the current plotted
on the Y axis and voltage on the X axis) has an "S"-shape.
SEE OR SEARCH THIS CLASS, SUBCLASS:
196 for a stable state circuit utilizing an "S"-shape
negative resistance diode.
Subclass:
501
Hyperconductive diode:
This subclass is indented under subclass 500. Subject matter
wherein the solid-state device is a four layer threshold
diode, one of whose outer layers is metal and wherein at a
predetermined reverse voltage point, junction breakdown
occurs to provide high current at very low voltages.
Subclass:
502
Breakdown characteristic (e.g., zener diode, etc.):
This subclass is indented under subclass 493. Subject matter
wherein the operation of the solid-state device is
characterized by a sudden change from high dynamic electrical
resistance to a very low dynamic resistance in a reverse
biased semiconductor device (e.g., a reverse biased junction
between p-type and n-type semiconductor materials, wherein
reverse current increases rapidly for a small increase in
reverse applied voltage, and the device behaves as if it had
negative electrical resistance).
(1) Note. An example of the breakdown characteristic is
zener breakdown which is caused by the field emission of
charge carriers in the depletion layer of the semiconductor
device. When breakdown occurs, the electric field intensity
in the material has become so great that electrons are
effectively "ripped" from the valency bonding system.
SEE OR SEARCH THIS CLASS, SUBCLASS:
580 for miscellaneous circuits utilizing a breakdown
transistor device.
584 for miscellaneous circuits utilizing a breakdown diode.
Subclass:
503
PIN diode:
This subclass is indented under subclass 493. Subject matter
including a two layer region (p and n), two electrode, single
junction semiconductor device which has an intrinsic
semiconductor (i.e., one with no dopants) sandwiched between
a p-type layer, and an n-type layer.
Subclass:
504
PN junction diode
This subclass is indented under subclass 493. Subject matter
wherein the solid-state device has two regions, two terminals
(anode and cathode), a single junction and conducts
electricity much more easily in one direction than in the
other.
Subclass:
505
Inverse parallel connection:
This subclass is indented under subclass 504. Subject matter
wherein two diodes are connected across each other, but in
opposite directions (i.e., the cathode of one device is
joined to the anode of the other device at one common node
and vice versa at the other common node).
Subclass:
506
Three or more electrode electron tube:
This subclass is indented under subclass 365. Subject matter
including a vacuum or gas filled tube having three or more
electrodes in which electrical currents flow between spaced
electrodes and in which the conduction of charged particles
(e.g., electrons), takes place between the electrodes.
Subclass:
507
Two electrode electron tube:
This subclass is indented under subclass 365. Subject matter
including a vacuum or gas filled tube having two electrodes
in which electrical currents flow between spaced electrodes,
and in which the conduction of charged particles (e.g.,
electrons), takes place between electrodes.
Subclass:
508
Bridge circuit:
This subclass is indented under subclass 507. Subject matter
including four two-electrode electron tubes with their input
and output terminals connected in a closed loop to form a
four arm network.
SEE OR SEARCH THIS CLASS, SUBCLASS:
588 for miscellaneous bridge circuits.
Subclass:
509
EXTERNAL EFFECT:
This subclass is indented under the class definition.
Subject matter wherein the operation of the circuit or system
depends upon some externally applied force or field such as
radiation, light, heat, sound, mechanical pressure, etc., or
where compensation for the effects of such externally applied
force or field is provided.
SEE OR SEARCH THIS CLASS, SUBCLASS:
187 for two or more stable state circuits using external
effect devices.
SEE OR SEARCH CLASS:
73, Measuring and Testing, appropriate subclasses for sensing
various types of external influence such as, fluid pressure,
vibration, etc.
257, Active Solid-State Devices (e.g., Transistors,
Solid-State Diodes), 414 for active solid-state devices, per
se, responsive to a non-electrical signal.
307, Electrical Transmission or Interconnection Systems,
appropriate subclasses (e.g., 116, 401+, 650+, etc.) for
transmission or interconnection systems which are condition
responsive.
438, Semiconductor Device Manufacturing: Process, 48 for
methods of making semiconductor devices which respond to
nonelectrical stimuli.
Subclass:
510
Magnetic:
This subclass is indented under subclass 509. Subject matter
wherein the external effect involves a magnetic field.
SEE OR SEARCH CLASS:
257, Active Solid-State Devices (e.g., Transistors,
Solid-State Diodes), 421 for a magnetic responsive
semiconductor element, per se.
307, Electrical Transmission or Interconnection Systems, 401
for nonlinear reactor systems including magnetic reactors.
324, Electricity: Measuring and Testing, 244 and
particularly subclasses 250 and 252 for magnetometers with
indicators.
330, Amplifiers, subclass 4.8 for gyromagnetic parametric
amplifiers, subclass 6 for amplifiers with Hall effect type
means, subclass 8 for saturable reactor type amplifiers,
subclasses 47+ for magnetically influenced discharge device
amplifiers, subclass 60 for magnetrostrictive type amplifiers
and subclass 63 for amplifiers with magnetic means
generally.
331, Oscillators, subclass 5 and 86+ for magnetron
oscillators, subclasses 6, 83, and 84 for Klystron
oscillators and subclass 67 for oscillators with
electromagnetic or electrostatic shielding.
338, Electrical Resistors, subclass 32 for resistance means
whose value depends upon an applied magnetic field and see
also the search notes thereunder.
341, Coded Data Generation or Conversion, subclass 15 for a
magnetic digital pattern reading converter.
Subclass:
511
Utilizing Hall effect:
This subclass is indented under subclass 510. Subject matter
wherein a magnetic field is applied to a current carrying
conductor and use is made of the voltage which is produced
between opposing edges of the conductor and which is
perpendicular to both the current and the magnetic field.
SEE OR SEARCH THIS CLASS, SUBCLASS:
187 for a stable state circuit which is externally
controlled.
SEE OR SEARCH CLASS:
257, Active Solid-State Devices (e.g., Transistors,
Solid-State Diodes), 421 for a magnetic responsive
semiconductor element, per se.
324, Electricity: Measuring and Testing, subclass 251 for a
Hall plate magnetometer with indicator.
Subclass:
512
Temperature:
This subclass is indented under subclass 509. Subject matter
wherein the external effect involves heat or thermal energy.
SEE OR SEARCH CLASS:
257, Active Solid-State Devices (e.g., Transistors,
Solid-State Diodes), 467 for a heat responsive
semiconducting element, per se.
331, Oscillators, subclass 66 for a temperature controlled
oscillator and subclass 70 for oscillators with temperature
modifiers and see the search notes thereunder.
338, Electrical Resistors, 25 for resistors whose value is
responsive to ambient temperature and see the search notes
thereunder.
340, Communications: Electrical, 584 for thermal condition
responsive indicating systems.
374, Thermal Measuring and Testing, subclass 163 for a
thermal sensor with quantitative indicator and subclass 178
for an electrical thermometer having a barrier layer sensing
element.
Subclass:
513
With compensation for temperature fluctuations:
This subclass is indented under subclass 512. Subject matter
wherein circuit anomalies resulting from variations in
ambient thermal conditions are counterbalanced.
SEE OR SEARCH THIS CLASS, SUBCLASS:
83 138, 262, and 378, for diverse types of temperature
compensation.
SEE OR SEARCH CLASS:
323, Electricity: Power Supply or Regulation Systems,
subclass 907 for a voltage control circuit having
temperature compensation of a semiconductor.
326, Electronic Digital Logic Circuits, subclass 32 for
temperature compensation in signal level or switching
threshold stabilization.
330, Amplifiers, subclass 289 for a temperature compensated
semiconductor amplifier.
Subclass:
514
Light:
This subclass is indented under subclass 509. Subject matter
wherein the external effect involves energy of optical
wavelengths.
(1) Note. Secondary emissive circuits which may utilize a
light sensitive cathode are classified below.
SEE OR SEARCH THIS CLASS, SUBCLASS:
573 for a secondary emissive circuit which utilizes a light
sensitive cathode.
SEE OR SEARCH CLASS:
250, Radiant Energy, 200 for circuits using photocells and
see also the search notes thereunder.
257, Active Solid-State Devices (e.g., Transistors,
Solid-State Diodes), 431 for a light responsive
semiconducting element, per se.
359, Optics: Systems (Including Communication) and Elements,
appropriate subclasses for miscellaneous optical systems and
elements.
Subclass:
515
Elements forming an array:
This subclass is indented under subclass 514. Subject matter
wherein plural light effect elements are arranged into a
matrix having defined rows and columns.
SEE OR SEARCH CLASS:
348, Television, 294 for a solid-state television image
sensor having elements in an array.
Subclass:
516
Utilizing conversion of mechanical variations into electrical
variations (e.g., vibration sensitive, etc.):
This subclass is indented under subclass 509. Subject matter
wherein an element of a circuit or system is responsive to
the application of physical energy.
SEE OR SEARCH THIS CLASS, SUBCLASS:
517 for miscellaneous touch or proximity sensitive
circuits.
SEE OR SEARCH CLASS:
257, Active Solid-State Devices (e.g., Transistors,
Solid-State Diodes), 415 for a pressure responsive
semiconducting element, per se.
Subclass:
517
Responsive to proximity or touch:
This subclass is indented under subclass 509. Subject matter
wherein the operation of a circuit or system is modified by
the approach of or slight contact with a physical object.
SEE OR SEARCH THIS CLASS, SUBCLASS:
516 for circuitry which utilizes the conversion of
mechanical variations into electrical variations.
SEE OR SEARCH CLASS:
340, Communications: Electrical, subclass 407 for tactual
communication circuits.
361, Electricity: Electrical Systems and Devices, 179 for
relays or solenoids responsive to proximity or contact.
Subclass:
518
WITH PARTICULAR CONTROL:
This subclass is indented under the class definition.
Subject matter wherein a controlling means is a nonlinear
device, circuit, or system which specifically controls the
delivery of current or power to a load device connected to
its output terminal in response to a control signal applied
to its input terminal.
(1) Note. A load device as included in this subclass may
include any load which is so broadly claimed as not to
restrict the system to any specific class or subclass. Where
a specific load device is claimed, classification will be in
the particular class wherein the art device comprising the
specific load device is to be found.
(2) Note. Systems not especially concerned with the
delivery of current or power to the load device, but
concerned instead with the control of a circuit parameter
such as phase, frequency, or amplitude are excluded from this
subclass.
SEE OR SEARCH THIS CLASS, SUBCLASS:
407 for a plurality of inputs appearing over a plurality of
input channels selectively switched to a single output
channel.
415 for means whereby a single input appearing over a single
channel is selectively switched to a plurality of output
channels.
Subclass:
519
Plurality of load devices:
This subclass is indented under subclass 518. Subject matter
wherein the output of the nonlinear device, circuit, or
system is connected to a multiple of controlled load
devices.
(1) Note. Systems where current or voltage is applied to
plural output loads selectively or successively as a result
of a scanning operation are excluded from this subclass and
will be found elsewhere in the class.
SEE OR SEARCH CLASS:
307, Electrical Transmission or Interconnection Systems, 11
for electrical interconnections feeding plural loads.
315, Electric Lamp and Discharge Devices: Systems,
appropriate subclasses for circuits containing plural
discharge device loads.
318, Electricity: Motive Power Systems, appropriate
subclasses, especially 34 for plural diverse or diversely
controlled electric motors, with systems of electrical supply
or control for one or more electric motors where the electric
motor is claimed in combination with such systems or control
and the electric motor as claimed constitutes the ultimate
load.
330, Amplifiers, subclass 73, 84, 124+, 148, and 295 for
amplifier systems having plural loads.
331, Oscillators, subclass 2 and 46+ for plural oscillator
systems which may have plural loads and subclass 60 for a
single oscillator system with plural output circuits.
361, Electricity: Electrical Systems and Devices, 191 for
miscellaneous electric circuits controlling a plurality of
relay or electromagnetic load devices.
370, Multiplex Communications, appropriate subclasses for
similar subject matter used with multiplexing.
Subclass:
520
Plural active components included in a controlling circuit:
This subclass is indented under subclass 518. Subject matter
wherein the controlling means is constituted by a plurality
of active components such as transistors, amplifiers, or
space discharge devices.
(1) Note. Active components are components in a circuit
which have gain or direct current flow, such as transistors,
amplifiers, thyristors, electron tubes, or tunnels diodes.
SEE OR SEARCH THIS CLASS, SUBCLASS:
185 for stable state circuits with series connected tubes.
Subclass:
521
Connected in inverse parallel:
This subclass is indented under subclass 520. Subject matter
wherein a pair of active components in the controlling means
circuit are connected side-by-side in differing directions
between two circuit nodes.
(1) Note. For example, for a pair of electron tubes to be
connected in inverse parallel, the anode of one device is
connected to the cathode of another device and vice versa.
SEE OR SEARCH CLASS:
315, Electric Lamp and Discharge Devices: Systems, 196 and
251 for inverse parallel connected space discharge load
devices.
323, Electricity: Power Supply or Regulation Systems,
subclass 227 and 291 for voltage magnitude control systems
with plural electric discharge devices reversely connected in
parallel.
Subclass:
522
Gaseous tube:
This subclass is indented under subclass 520. Subject matter
wherein the active components include an electronic tube into
which a small amount of gas or vapor is introduced after the
tube has been evacuated.
SEE OR SEARCH THIS CLASS, SUBCLASS:
601 for miscellaneous circuits having gas tubes of
particular structure.
SEE OR SEARCH CLASS:
315, Electric Lamp and Discharge Devices: Systems,
appropriate subclasses for system wherein a gaseous space
discharge tube is the ultimate load or controls a space
discharge load.
Subclass:
523
Gaseous tube:
This subclass is indented under subclass 518. Subject matter
wherein the controlling means includes an electronic tube
into which a small amount of gas or vapor is introduced after
the tube has been evacuated.
SEE OR SEARCH THIS CLASS, SUBCLASS:
601 for miscellaneous circuits having gas tubes of
particular structure.
SEE OR SEARCH CLASS:
315, Electric Lamp and Discharge Devices: Systems,
appropriate subclasses for system wherein a gaseous space
discharge tube is the ultimate load or controls a space
discharge load.
Subclass:
524
SPECIFIC IDENTIFIABLE DEVICE, CIRCUIT, OR SYSTEM:
This subclass is indented under the class definition.
Subject matter wherein a nonlinear device, circuit, or system
has a particular structure, arrangement, or construction that
is not classifiable elsewhere.
(1) Note. This subclass and the indented subclasses contain
subject matter which is neither sufficiently comprehensive
nor possessive of sufficiently significant structure so as to
be classified with a specific external area.
SEE OR SEARCH CLASS:
313, Electric Lamp and Discharge Devices, appropriate
subclasses for the structure of space discharge devices.
315, Electric Lamp and Discharge Devices: Systems, 3 and
32+ for combined tube and circuit element structure,
subclasses 5.18+ and 5.24+ for reflex type beam tube
circuits, and subclasses 88+ for automatic space discharge
device substitution systems.
330, Amplifiers, subclass 3 for amplifiers with plural
diverse amplifying devices, subclasses 4, 5, 43, 45, 47, and
49 wherein the internal tube structure forms part of the
amplifier control circuit, subclasses 41, 42, 44+, and 64 for
amplifier systems utilizing tubes of particular construction,
subclasses 51, 52, 65+, and 127+ for systems that may include
tube substitution; subclasses 87+, and the search notes
thereto, for cathode follower amplifier systems; and
subclasses 127+ for amplifier bias voltage control systems.
331, Oscillators, subclass 5, 6+, 103, 126+, and 184 for
oscillator systems utilizing tubes of particular
construction; subclass 49 for oscillator substitution
systems; subclass 84 for beam tube oscillators of the reflex
type; subclasses 79+, 86+, 92+, and 103 wherein the internal
tube structure may form part of the oscillator control
circuit; and subclass 186 for oscillator bias voltage
regulation.
376, Induced Nuclear Reactions: Processes, Systems, and
Elements, 100 for subject matter of this subclass (524) when
utilized in connection with plasma in the generation of
thermonuclear reactions.
Subclass:
525
Fusible link or intentional destruct circuit:
This subclass is indented under subclass 524. Subject matter
wherein an element burns out or is destroyed (i.e., is open
circuited) in an interconnection or integrated circuit
structure component when applied current or voltage exceeds a
predetermined limit.
SEE OR SEARCH CLASS:
102, Ammunition and Explosives, appropriate subclasses for
fuses relating to munitions.
326, Electronic Digital Logic Circuitry, 37 for programmable
logic.
365, Static Information Storage and Retrieval, subclass 96
for fusible links relating to programmable read-only memory
and subclass 200 for eliminating "bad bit" information
associated with read/write circuits.
438, Semiconductor Device Manufacturing: Process, subclass
467, 600, and 601 for methods of altering the conductivity of
a fuse or antifuse element associated with a semiconductor
integrated circuit.
Subclass:
526
Redundant:
This subclass is indented under subclass 524. Subject matter
wherein there is a duplication of components, devices,
circuits, elements, etc., such that a duplicate will assume
operation upon failure of the original.
SEE OR SEARCH CLASS:
326, Electronic Digital Logic Circuitry, 10 for redundant
logic circuits.
714, Error Detection/Correction and Fault Detection/Recovery,
3 for fault recovery by replacement with a spare device.
Subclass:
527
Superconductive (e.g., cryogenic, etc.) device:
This subclass is indented under subclass 524. Subject matter
including a particular circuit which operates at temperatures
which are approximately absolute zero (i.e., less than or
equal to 30 K) where electrical resistance becomes
essentially zero.
(1) Note. Class 505 comprises superconductive devices which
operate at a temperature higher than 30 K.
SEE OR SEARCH THIS CLASS, SUBCLASS:
186 for one or more stable state cryogenic circuits.
366 for cryogenic gating or switching.
SEE OR SEARCH CLASS:
326, Electronic Digital Logic Circuitry, 1 for
superconductor logic circuits.
338, Electrical Resistors, subclass 32 for a resistive
element whose resistance depends on the value of an applied
magnetic field.
340, Communications: Electrical, subclass 825.79 for matrix
systems using superconductive elements.
365, Static Information Storage and Retrieval, 160 for
information storage means using superconductive elements.
505, Superconductor Technology: Apparatus, Material,
Process, appropriate subclasses for superconductive devices
operating above 30 K.
Subclass:
528
Josephson junction:
This subclass is indented under subclass 527. Subject matter
wherein a current flows across a gap between two
superconductors separated by a thin layer of insulator.
(1) Note. Under certain conditions, a voltage appears
across the gap, and high-frequency radiation emanates from
it.
Subclass:
529
Impact ionization:
This subclass is indented under subclass 527. Subject matter
wherein a breakdown can occur within a semiconductor device
as a result of operation at temperatures approaching absolute
zero (temperatures equal to or lower than 30 K).
SEE OR SEARCH THIS CLASS, SUBCLASS:
186 for one or more stable state circuits including an
impact ionization device.
Subclass:
530
With specific source of supply or bias voltage:
This subclass is indented under subclass 524. Subject matter
wherein either (a) a DC bias potential other than signal
voltage is applied or maintained between two or more
electrodes in order to determine the operating point on the
characteristic curve of a device or (b) electrical power or
bias voltage is applied to a region of a nonlinear
solid-state device or circuit.
(1) Note. The claimed subject matter does not comprise
significant structure so as to limit the power supply to
those provided for in a particular art area.
(2) Note. The systems found in this class may include means
to supply current to the anode or filament, a potential to
the grid of an electron tube (which is usually negative with
respect to the cathode), or establishing or maintaining a
direct current voltage between two elements of an electron
tube.
(3) Note. Claimed subject matter having biasing on and off
wherein a switched input is identical to the output will be
classified in subclasses 365+.
SEE OR SEARCH THIS CLASS, SUBCLASS:
365 for switching input supply or bias to the output wherein
the input signal is the same as the output signal.
531 for biasing systems in identifiable circuits, in
general.
535 for biasing or power supply circuitry with significant
stabilizing circuitry for regulating the bias or power supply
level.
597 for particular grid control systems.
SEE OR SEARCH CLASS:
307, Electrical Transmission or Interconnection Systems, 18,
31+, and 43+ for plural power supplies, and subclass 150 for
miscellaneous power packs, per se.
315, Electric Lamp and Discharge Devices, Systems, 1 for
cathode-ray tube power supply circuits, subclasses 86+ for
power supply systems for space discharge devices, in general,
with automatic substitution in the power supply, subclasses
137+ for polyphase AC supply circuits, subclasses 160+ for
plural power supplies, subclasses 200+ for circuits having a
discharge device and/or rectifier in the supply circuit,
subclass 209 for circuits having a periodic switch in the
supply circuit, subclasses 227+ for circuits with a condenser
in the supply circuit, and subclasses 248+ for a pulsating or
AC supply circuit.
323, Electricity: Power Supply or Regulation Systems, 311
for circuits that supply a regulated voltage, current or
power to a nonspecific or general load device.
330, Amplifiers, subclass 113 for polyphase power supply
systems, subclasses 114+ for unrectified AC power supply
systems, subclasses 127+ for amplifier tube biasing systems
subclasses 199+ for power or bias supplies, in general, and
subclasses 296 and 297 having particular power supply or
biasing for linear amplifier circuits or systems.
331, Oscillators, 185 for particular sources of power or
bias for oscillators.
363, Electric Power Conversion Systems, subclasses,
particularly 13 for rectifying or derectifying systems which
may include electron tubes and their control.
378, X-Ray or Gamma Ray Systems or Devices, 91 for X-ray
device circuits.
Subclass:
531
Fluctuating or AC source with rectifier or filter:
This subclass is indented under subclass 530. Subject matter
wherein the power supply is converted from an alternating or
fluctuating input voltage or current to a direct current or
voltage via a rectifier circuit or is smoothed or integrated
by a filter circuit.
(1) Note. The power supply may contain both AC and DC
components, and the DC component is received from the output
by coupling to a rectifier or a filter circuit.
SEE OR SEARCH THIS CLASS, SUBCLASS:
104 for AC waveform to DC waveform output conversion at an
unloaded output.
330 for amplitude limiting systems with a rectifier.
552 for unwanted component eliminating systems with a
filter.
SEE OR SEARCH CLASS:
363, Electric Power Conversion Systems, 44 for rectifier
systems with smoothing filters.
Subclass:
532
With particular filter circuit:
This subclass is indented under subclass 531. Subject matter
including a filter circuit with specific structure.
SEE OR SEARCH THIS CLASS, SUBCLASS:
552 for unwanted component eliminating utilizing a filter.
SEE OR SEARCH CLASS:
333, Wave Transmission Lines and Networks, 167 for passive
wave filters, especially subclasses 181+ for smoothing type
filters.
Subclass:
533
With battery connected across rectifier:
This subclass is indented under subclass 531. Subject matter
wherein the conversion is accomplished via a battery
connected across or in shunt with a rectifier.
SEE OR SEARCH CLASS:
307, Electrical Transmission or Interconnection Systems, 44
for systems wherein one source floats across another, see
particularly subclasses 46 and 48+ for floating sources of
the storage battery type.
Subclass:
534
Having particular substrate biasing:
This subclass is indented under subclass 530. Subject matter
wherein a potential is applied to a substrate region of a
nonlinear element or solid-state device.
SEE OR SEARCH CLASS:
365, Static Information Storage and Retrieval, appropriate
subclass for electromagnetic storage systems, 185.01 for
floating gate memory storage (e.g., flash memory).
Subclass:
535
Having stabilized bias or power supply level:
This subclass is indented under subclass 534. Subject matter
wherein the bias or power supply level provided to the
substrate of a nonlinear element or solid-state device is
maintained constant.
(1) Note. The stabilization may be for either voltage or
current level to compensate for adverse conditions (e.g.,
nonuniformity of integrated chip structure, supply level
perturbations, etc.).
SEE OR SEARCH THIS CLASS, SUBCLASS:
540 for stabilized electron tube circuits with voltage
regulation.
SEE OR SEARCH CLASS:
318, Electricity: Motive Power Systems, appropriate
subclasses for motor power supply or speed control or
regulation.
323, Electricity: Power Supply or Regulation Systems, 311
for circuits that supply a regulated voltage, current, or
power to a nonspecific or general load device.
Subclass:
536
Charge pump details:
This subclass is indented under subclass 535. Subject matter
wherein the particular substrate biasing circuit is regulated
by a significantly recited electrical circuit arrangement for
pumping electric charges (electrons (negative charges) or
protons (positive charges)) into or out of the substrate to
polarize the substrate at a negative or positive potential
which is the generated bias voltage.
Subclass:
537
With field-effect transistor:
This subclass is indented under subclass 535. Subject matter
including a unipolar transistor in which current carriers are
injected at a source terminal and pass to a drain terminal
through a channel of semiconductor material whose
conductivity depends largely on an electric field applied to
the semiconductor from a control terminal (gate).
(1) Note. In a unipolar transistor, the source to drain
current involves only one type of charge carrier (i.e., holes
in a p-type material channel and electrons in an n-type
material channel).
(2) Note. Two types of FET structures are prevalent: (a)
an all-junction device, known as a junction FET or JFET
characterized by having heavily doped impurity regions of one
type (e.g., p-type material), known as gate regions, on both
sides of a second type semiconductor bar (e.g., n+ type
material) to form a pn junction, and (b) a device such as a
MOSFET/IGFET, consisting of a lightly doped substrate (e.g.,
p-type material) into which two highly doped regions (e.g.,
n+ type material) are diffused for forming source/drain
regions with the area therebetween becoming the channel for
current carriers (i.e., holes or electrons) and with a layer
of insulating material (e.g., SiO[subscrpt]2[end subscrpt])
grown over the channel surface for separating the channel
from a control (i.e., gate) electrode.
Subclass:
538
Stabilized (e.g., compensated, regulated, maintained, etc.):
This subclass is indented under subclass 530. Subject matter
wherein the bias circuit or a particular arrangement of the
power supply offsets undesired changes in the circuit signals
or maintains the circuit in its normal operating state.
SEE OR SEARCH THIS CLASS, SUBCLASS:
535 for particular substrate biasing with stabilized bias or
power supply level.
Subclass:
539
Using bandgap:
This subclass is indented under subclass 538. Subject matter
wherein a bandgap voltage of a semiconductor material is
provided as a reference to compensate for variations of the
voltage supply.
(1) Note. Bandgap voltage is the difference in energy
between the conduction band and the valence band in a
semiconductor material (e.g., the bandgap voltage of
silicon).
Subclass:
540
With voltage source regulating:
This subclass is indented under subclass 538. Subject matter
wherein a voltage supplied to the electrodes of a space
discharge device or to a solid-state device is maintained
constant at a predetermined value.
SEE OR SEARCH THIS CLASS, SUBCLASS:
306 for amplitude control systems of a converted or shaped
signal.
SEE OR SEARCH CLASS:
315, Electric Lamp and Discharge Devices: Systems, subclass
287 for periodic types of current or voltage regulator used
with pulsating or AC supplies and subclasses 291+ for current
or voltage regulation systems where the discharge device is
the ultimate load claimed.
323, Electricity: Power Supply or Regulation Systems,
subclass 227 and 291 for voltage magnitude control systems
with electron discharge devices where there is no interposed
signal controlled transducer between the original and
controlled energy.
330, Amplifiers, 127 for control of amplifier power supplies
or bias voltages.
331, Oscillators, subclass 186 for oscillators with
regulated power supplies.
363, Electric Power Conversion Systems, 74 for voltage or
magnitude control for current conversion systems (e.g.,
rectification, derectification, etc.).
Subclass:
541
With field-effect transistor:
This subclass is indented under subclass 540. Subject matter
including a unipolar transistor in which current carriers are
injected at a source terminal and pass to a drain terminal
through a channel of semiconductor material whose
conductivity depends largely on an electric field applied to
the semiconductor from a control terminal (gate).
(1) Note. In a unipolar transistor, the source to drain
current involves only one type of charge carriers (i.e.,
holes in a p-type material channel and electrons in an n-type
material channel).
(2) Note. Two types of FET structures are prevalent: (a)
an all-junction device, known as a junction FET or JFET
characterized by having heavily doped impurity regions of one
type (e.g., p-type material), known as gate regions, on both
sides of a second type semiconductor bar (e.g., n+ type
material) to form a pn junction, and (b) a device such as a
MOSFET/IGFET, consisting of a lightly doped substrate (e.g.,
p-type material) into which two highly doped regions (e.g.,
n+ type material) are diffused for forming source/drain
regions with the area therebetween becoming the channel for
current carriers (i.e., holes or electrons) and with a layer
of insulating material (e.g., SiO[subscrpt]2[end subscrpt])
grown over the channel surface for separating the channel
from a control (i.e., gate) electrode.
SEE OR SEARCH THIS CLASS, SUBCLASS:
537 for particular substrate biasing circuit with a
field-effect transistor.
Subclass:
542
With diverse type transistor devices:
This subclass is indented under subclass 538. Subject matter
including different types of transistors in the same
circuit.
Subclass:
543
Using field-effect transistor:
This subclass is indented under subclass 538. Subject matter
wherein the circuit includes only one type of transistor
which is a unipolar transistor in which current carriers are
injected at a source terminal and pass to a drain terminal
through a channel of semiconductor material whose
conductivity depends largely on an electric field applied to
the semiconductor from a control terminal (gate).
(1) Note. In a unipolar transistor, the source to drain
current involves only one type of charge carriers (i.e.,
holes in a p-type material channel and electrons in an n-type
material channel).
(2) Note. Two types of FET structures are prevalent: (a)
an all-junction device, known as a junction FET or JFET
characterized by having heavily doped impurity regions of one
type (e.g., p-type material), known as gate regions, on both
sides of a second type semiconductor bar (e.g., n+ type
material) to form a pn junction, and (b) a device such as a
MOSFET/IGFET, consisting of a lightly doped substrate (e.g.,
p-type material) into which two highly doped regions (e.g.,
n+ type material) are diffused for forming source/drain
regions with the area therebetween becoming the channel for
current carriers (i.e., holes or electrons) and with a layer
of insulating material (e.g., SiO[subscrpt]2[end subscrpt])
grown over the channel surface for separating the channel
from a control (i.e., gate) electrode.
SEE OR SEARCH THIS CLASS, SUBCLASS:
537 for a particular substrate biasing circuit with a
field-effect transistor.
541 for a stabilized circuit with current or voltage
regulating using a field-effect transistor.
Subclass:
544
Power conservation or pulse type:
This subclass is indented under subclass 530. Subject matter
wherein the power supply or bias level is reduced to conserve
power or a power supply is provided for biasing having a
periodic or nonperiodic pulsing type characteristic.
SEE OR SEARCH THIS CLASS, SUBCLASS:
100 for signal converting, shaping, or generating and,
particularly, subclasses 291+ for clock type signal
generation.
545 for monitoring for supply or bias preservation.
SEE OR SEARCH CLASS:
365, Static Information Storage and Retrieval, subclass 227
for power conservation in memory systems.
368, Horology: Time Measuring Systems or Devices, subclass
66 for power source control for timekeeping devices.
Subclass:
545
Including signal protection or bias preservation:
This subclass is indented under subclass 530. Subject matter
wherein a circuit is provided which guards against signal
information loss or bias loss.
SEE OR SEARCH THIS CLASS, SUBCLASS:
379 for gating circuitry with means to maintain signal
transmission.
392 for time delay circuits to control switching
operations.
SEE OR SEARCH CLASS:
324, Electricity: Measuring and Testing, 51 for circuit
fault detection and testing, per se.
326, Electronic Digital Logic Circuitry, 21 for digital
logic circuits or systems for improving reception sensitivity
and maintaining transmission integrity.
340, Communications: Electrical, subclass 636 for battery
level condition responsive systems.
365, Static Information Storage and Retrieval, subclass 228
for memory systems with provision for prevention of data loss
(e.g., backup storage or power).
368, Horology: Time Measuring Systems or Devices, subclass
66 for power source monitoring of chronological timepieces.
714, Error Detection/Correction and Fault Detection/Recovery,
appropriate subclasses for subject matter limited to
particular loss of data by transmission apparatus or to the
recovery of information from error or Fault operating
conditions (e.g., pulse coded data).
Subclass:
546
With field-effect transistor:
This subclass is indented under subclass 545. Subject matter
including a unipolar transistor in which current carriers are
injected at a source terminal and pass to a drain terminal
through a channel of semiconductor material whose
conductivity depends largely on an electric field applied to
the semiconductor from a control terminal (gate).
(1) Note. In a unipolar transistor, the source to drain
current involves only one type of charge carrier (i.e., holes
in a p-type material channel and electrons in an n-type
material channel).
(2) Note. Two types of FET structures are prevalent: (a)
an all-junction device, known as a junction FET or JFET
characterized by having heavily doped impurity regions of one
type (e.g., p-type material), known as gate regions, on both
sides of a second type semiconductor bar (e.g., n+ type
material) to form a pn junction, and (b) a device such as a
MOSFET/IGFET, consisting of a lightly doped substrate (e.g.,
p-type material) into which two highly doped regions (e.g.,
n+ type material) are diffused for forming source/drain
regions with the area therebetween becoming the channel for
current carriers (i.e., holes or electrons) and with a layer
of insulating material (e.g., SiO[subscrpt]2[end subscrpt])
grown over the channel surface for separating the channel
from a control (i.e., gate) electrode.
SEE OR SEARCH THIS CLASS, SUBCLASS:
537 for particular substrate biasing circuit with
field-effect transistor.
541 for a stabilized circuit with current or voltage
regulating using a field-effect transistor.
543 for a stabilized circuit with a field-effect
transistor.
Subclass:
547
With selectively or alternately DC or AC input:
This subclass is indented under subclass 530. Subject matter
wherein a DC or AC power is selectively or alternately
supplied to the input of the circuit device.
SEE OR SEARCH CLASS:
307, Electrical Transmission or Interconnection Systems, 18
and 43+ for plural power supplies, particularly subclasses
23, 29, 64+, or 80+ for selective, substitute, or alternate
sources.
Subclass:
548
With oscillator or interrupter:
This subclass is indented under subclass 530. Subject matter
wherein the power supply employs an oscillatory circuit as a
source of varying current.
(1) Note. The oscillatory circuit may comprise an
interrupting type network.
SEE OR SEARCH THIS CLASS, SUBCLASS:
100 for non-free running signal generation, and particularly
124 for chopper type generation.
596 for miscellaneous oscillatory or shock excited
circuits.
SEE OR SEARCH CLASS:
310, Electrical Generator or Motor Structure, 10 for
dynamoelectric generating apparatus, particularly subclass 25
for reed type, subclass 26 for magneto structure type, and
subclasses 31+ for self actuated interrupter type current
generating devices.
330, Amplifiers, subclass 9 for amplifier circuits in which
the input signal is periodically interrupted or derectified,
applied to the amplifier, and then rectified and subclass 137
where an oscillator supplies or controls bias voltage.
331, Oscillators, appropriate subclasses for self-sustaining
wave generators, per se.
363, Electric Power Conversion Systems, 15 for
inverter-rectifiers (DC to AC to DC systems), subclasses 102+
for dynamoelectric machine current converters, and subclasses
106+ for circuit interrupter type current converters.
Subclass:
549
With hum or interaction prevention:
This subclass is indented under subclass 530. Subject matter
wherein alternating or hum components in an output of a power
supply are prevented from appearing in the output system
circuit.
SEE OR SEARCH THIS CLASS, SUBCLASS:
551 for miscellaneous unwanted signal elimination.
SEE OR SEARCH CLASS:
330, Amplifiers, subclass 149 for bucking hum, noise or
distortion introduced into the amplifier signal channel.
363, Electric Power Conversion Systems, 39 for current
conversion systems that introduce or eliminate frequency
components.
381, Electrical Audio Signal Processing Systems and Devices,
appropriate subclasses for audio signal noise suppression.
Subclass:
550
With particular filament heating circuit:
This subclass is indented under subclass 530. Subject matter
wherein a filament heating circuit with specific structure
provides a current to heat the filament of an electron space
discharge tube.
SEE OR SEARCH CLASS:
315, Electric Lamp and Discharge Devices: Systems, 94 for
cathode or cathode heater supply circuits.
330, Amplifiers, 199 especially subclass 206 for filamentary
heating of the filaments of an amplifier.
Subclass:
551
Unwanted signal suppression:
This subclass is indented under subclass 524. Subject matter
wherein an undesired signal or group of signals is diminished
and wherein such subject matter is not elsewhere
classifiable.
SEE OR SEARCH THIS CLASS, SUBCLASS:
98 for separating composite signals.
310 for transient or signal noise reduction by limiting,
clipping, or clamping.
SEE OR SEARCH CLASS:
326, Electronic Digital Logic Circuitry, 21 for signal
sensitivity or transmission integrity which includes input
noise margin enhancement.
Subclass:
552
Active filter:
This subclass is indented under subclass 551. Subject matter
wherein a specified frequency or a range of frequencies of an
input signal is passed or blocked by the use of an active
device.
(1) Note. Filter circuits that do not include any active
element, such as a transistor, an amplifier, etc., and are
constituted by distributed parameters, lumped parameters,
long line elements, or passive elements (resistors,
capacitors, or inductors) are excluded from this subclass and
are classified primarily in Class 333, Wave Transmission
Lines and Networks.
(2) Note. Filter circuits involving a systematic operation
on data which results in a significant change in data are
classified elsewhere.
SEE OR SEARCH THIS CLASS, SUBCLASS:
311 for transient or signal noise reduction in a filtered
limiting, clipping, or clamping circuit.
379 for a gating circuit with spurious noise override.
SEE OR SEARCH CLASS:
181, Acoustics, 175 for sound filters.
307, Electrical Transmission or Interconnection Systems,
subclass 105 for a class appropriate harmonic filter or
neutralizer.
333, Wave Transmission Lines and Networks, subclass 28 for
equalizers, subclasses 165, 166, and 167+ for frequency or
time domain filters, subclass 202+ for wave filters including
long line elements.
340, Communications: Electrical, 825.71 for selective
communication systems which are frequency responsive.
363, Electric Power Conversion Systems, 39 for conversion
systems in combination with a filter.
375, Pulse or Digital Communications, subclass 103 for noise
filtering in a digital receiver.
708, Electrical Computers: Arithmetic Processing and
Calculating, 300 for filtering of data by a digital
calculating computer and subclass 819 for analog computer
filtering.
Subclass:
553
Adjustable:
This subclass is indented under subclass 552. Subject matter
wherein some component or parameter of a filter circuit (such
as filter resistor, filter capacitor, filter time constant,
filter amplifier gain, filter input signal, etc.) is
changeable in value by a control circuit signal.
Subclass:
554
Switched capacitor filter:
This subclass is indented under subclass 553. Subject matter
wherein a filter transfer function is determined by a
particular capacitor arrangement which is variable dependent
upon the switched connections controlled by an input clock
signal.
(1) Note. The frequency or timing of the input clock signal
dictates the characteristics and features of the signal
filtering function.
SEE OR SEARCH THIS CLASS, SUBCLASS:
291 for clock signal generating.
337 for an integrator having a switched capacitive
arrangement.
365 for the gating of an electrical signal between an input
and an output.
Subclass:
555
Selective type signal filtering (e.g., from low pass to high
pass, etc.):
This subclass is indented under subclass 553. Subject matter
wherein different types of signal filtering are selected by
an applied control signal.
(1) Note. The filter can be changed from one permitting low
frequency signals to flow through to one that only permits
high frequency signals to pass, (e.g.., low pass to high pass
filtering).
Subclass:
556
Notch or bandreject:
This subclass is indented under subclass 552. Subject matter
wherein a circuit arrangement attenuates a very narrow band
of frequencies of an input signal, but will pass frequencies
on either side (i.e., higher and lower frequencies) of the
narrow band.
Subclass:
557
Bandpass:
This subclass is indented under subclass 552. Subject matter
wherein a circuit arrangement attenuates frequencies on
either side of a predetermined range of frequencies of an
input signal.
Subclass:
558
Lowpass:
This subclass is indented under subclass 552. Subject matter
wherein a circuit arrangement allows passage of frequencies
of an input signal below a predetermined threshold frequency
and blocks passage of frequencies above that threshold.
Subclass:
559
Highpass:
This subclass is indented under subclass 552. Subject matter
wherein a circuit arrangement allows passage of frequencies
of an input signal above a predetermined threshold frequency
and blocks passage of frequencies below that threshold.
Subclass:
560
Nonlinear amplifying circuit:
This subclass is indented under subclass 524. Subject matter
wherein a non-linear circuit is combined with an amplifier in
which the output is not a substantial replica of the input
(e.g., the output is not linearly proportional to the input
of the circuit).
SEE OR SEARCH THIS CLASS, SUBCLASS:
334 for a circuit where the output signal is functionally
related to the input signal by a series of straight line
segments.
Subclass:
561
With operational amplifier:
This subclass is indented under subclass 560. Subject matter
wherein a nonlinear circuit is combined with a stable,
high-gain direct coupled amplifier that depends on an
external feedback from the output to the input of the circuit
to determine its functional characteristics (i.e., an
operational amplifier).
(1) Note. An operational amplifier classifiable in this
subclass must be combined with a source of signal energy or
with a load that constitutes a nonlinear circuit which is not
sufficiently comprehensive to be classified with a specific
art area.
SEE OR SEARCH CLASS:
330, Amplifiers, 75 for an amplifier with feedback.
381, Electrical Audio Signal Processing Systems and Devices,
111 for systems which include combinations of amplifier and
loud speaker or amplifier and microphone.
Subclass:
562
With field-effect transistor:
This subclass is indented under subclass 561. Subject matter
including a unipolar transistor in which current carriers are
injected at a source terminal and pass to a drain terminal
through a channel of semiconductor material whose
conductivity depends largely on an electric field applied to
the semiconductor from a control terminal (gate).
(1) Note. In a unipolar transistor, the source to drain
current involves only one type of charge carrier (i.e., holes
in a p-type material channel and electrons in an n-type
material channel).
(2) Note. Two types of FET structures are prevalent: (a)
an all-junction device, known as a junction FET or JFET
characterized by having heavily doped impurity regions of one
type (e.g., p-type material), known as gate regions, on both
sides of a second type semiconductor bar (e.g., n+ type
material) to form a pn junction, and (b) a device such as a
MOSFET/IGFET, consisting of a lightly doped substrate (e.g.,
p-type material) into which two highly doped regions (e.g.,
n+ type material) are diffused for forming source/drain
regions with the area therebetween becoming the channel for
current carriers (i.e., holes or electrons) and with a layer
of insulating material (e.g., SiO[subscrpt]2[end subscrpt])
grown over the channel surface for separating the channel
from a control (i.e., gate) electrode.
Subclass:
563
With differential amplifier:
This subclass is indented under subclass 560. Subject matter
wherein the non-linear circuit is combined with an amplifier
having two similar input circuits so connected as to respond
to the difference between two voltages (or currents) and
effectively suppress voltages or currents which are alike in
the two signals.
SEE OR SEARCH CLASS:
330, Amplifiers, 252 for semiconductor differential
amplifiers.
Subclass:
564
Integrated structure:
This subclass is indented under subclass 524. Subject matter
wherein a plurality of circuit elements or components are
formed on or in a single block of semiconductor material.
(1) Note. The following criteria are established to
distinguish patents proper for Class 327 from patents proper
for Class 257 (Active Solid-State Devices (e.g., Transistors,
Solid-State Diodes)): (a) a claimed integrated circuit (IC)
chip, per se, is classified in Class 257; (b) a claim to lead
frames, per se, is classified in Class 257 since these are
only used to connect an IC chip to the external environment;
(c) an IC chip claimed in combination with a single lead, a
battery, or bias without any configuration is classified in
Class 257 since no circuitry external to the chip is claimed;
(d) an IC chip claimed in combination with an external
circuit suitable for Class 327 will be classified in Class
327 since Class 327 is higher than Class 257 in the overall
class hierarchy; (e) circuit interconnections (e.g., point to
point, lead interconnections, diode and transistor
interconnections, etc.) within the confines of the IC chip
itself are classified in Class 257, whereas these same
interconnections outside the environment of an IC chip are
classified in Class 327; (f) if a specific or broad structure
of the IC is claimed with a utility, the patent will be
classified in the utility subclass, (e.g., Class 348
(Television), Class 365 (Static Information Storage and
Retrieval), etc.); (g) Charge Coupled Devices claimed as part
of the circuitry within an IC chip are classified in Class
257.
Subclass:
565
With specific layout or layout interconnections:
This subclass is indented under subclass 564. Subject matter
including specific design emphasis on the topological
arrangement of the components in the circuit and the circuit
connectors.
SEE OR SEARCH CLASS:
257, Active Solid-State Devices (e.g., Transistors,
Solid-State Diodes), appropriate subclasses for specific
nonlinear solid state devices with specific structure and
especially 202 for integrated chip devices having active
devices arrayed in a grid.
324, Electricity: Measuring and Testing, 73 for integrated
circuit chip structural arrangements/layouts including
monitoring or testing elements.
326, Electronic Digital Logic Circuitry, subclass 47 for
multifunctional or programmable logic circuits with specific
integrated structure layout or layout interconnections and
subclasses 101+ for integrated structure layout or layout
interconnections for digital logic circuits in general.
438, Semiconductor Device Manufacturing: Process,
particularly 128 and 598+ for methods of selectively
interconnecting semiconductor barrier layer-type device
arrays.
716, Data Processing: Design and Analysis of Circuit or
Semiconductor Mask, subclasses 1-18 for the design of
circuit systems and integrated circuit structure by data
processing and computer programming techniques.
Subclass:
566
Having field-effect transistor device:
This subclass is indented under subclass 565. Subject matter
including a unipolar transistor in which current carriers are
injected at a source terminal and pass to a drain terminal
through a channel of semiconductor material whose
conductivity depends largely on an electric field applied to
the semiconductor from a control terminal (gate).
(1) Note. In a unipolar transistor, the source to drain
current involves only one type of charge carriers (i.e.,
holes in a p-type material channel and electrons in an n-type
material channel).
(2) Note. Two types of FET structures are prevalent: (a)
an all-junction device, known as a junction FET or JFET
characterized by having heavily doped impurity regions of one
type (e.g., p-type material), known as gate regions, on both
sides of a second type semiconductor bar (e.g., n+ type
material) to form a pn junction, and (b) a device such as a
MOSFET/IGFET, consisting of a lightly doped substrate (e.g.,
p-type material) into which two highly doped regions (e.g.,
n+ type material) are diffused for forming source/drain
regions with the area therebetween becoming the channel for
current carriers (i.e., holes or electrons) and with a layer
of insulating material (e.g., SiO[subscrpt]2[end subscrpt])
grown over the channel surface for separating the channel
from a control (i.e., gate) electrode.
SEE OR SEARCH THIS CLASS, SUBCLASS:
581 for nonlinear solid-state device circuits and systems
with field-effect transistors, per se.
Subclass:
567
Thin film:
This subclass is indented under subclass 524. Subject matter
wherein a conductive, resistive, or capacitive passive
network is deposited under a form of thin patterned layer,
which is less than 5 micrometers in thickness, on a substrate
to form an electronic component that is included in a
nonlinear circuit or acts as a nonlinear element of the
circuit.
SEE OR SEARCH CLASS:
307, Electrical Transmission or Interconnection Systems,
subclass 403 for thin film parametrons in nonlinear reactor
systems.
Subclass:
568
Negative resistance type:
This subclass is indented under subclass 524. Subject matter
wherein an electron space discharge device or a solid-state
device included in the nonlinear circuit has a negatively
sloped portion in its current-voltage characteristic plot in
which an increase in voltage results in a decrease in
current.
(1) Note. Some examples of negative resistance tubes are
the dynatron and the transitron.
SEE OR SEARCH CLASS:
331, Oscillators, subclass 115 for negative resistance
semiconductor oscillators and subclasses 132+ for oscillatory
circuits utilizing a negative resistance or negative
transconductance tube means.
333, Wave Transmission Lines and Networks, 213 for negative
resistance or reactance networks of the active element type
comprising a two terminal network.
Subclass:
569
Unijunction transistor:
This subclass is indented under subclass 568. Subject matter
including a single junction three electrode solid-state
device with two of the electrodes being connected to one
region and the remaining electrode being connected to another
region wherein a signal applied to the latter electrode
causes a breakdown across the transistor junction allowing a
current to flow between the other two electrodes.
Subclass:
570
Having "N"-shape curve on I-V plot (e.g., tunnel diode type,
etc.):
This subclass is indented under subclass 568. Subject matter
including an electron space discharge device or a solid-state
device whose characteristic on a current versus voltage plot
(i.e., with the current plotted on the Y axis and voltage on
the X axis) has an "N"-shape.
(1) Note. A solid-state diode having modified physical
properties to reduce the amplitude of the negative slope
portion of the curve thereby providing threshold operation is
classified in this subclass.
SEE OR SEARCH THIS CLASS, SUBCLASS:
571 for a miscellaneous circuit having a device with an
"S"-shape negative resistance curve.
Subclass:
571
Having "S"-shape curve on I-V plot (e.g., pnpn diode type):
This subclass is indented under subclass 568. Subject matter
including a solid-state device whose characteristic on a
current versus voltage plot (i.e., with the current plotted
on the Y axis and voltage on the X axis) has an "S"-shape.
(1) Note. A solid-state four layer diode, one of whose
outer layers is a metal, breaks down at a predetermined
reverse voltage point junction to provide high current at low
voltages.
SEE OR SEARCH THIS CLASS, SUBCLASS:
570 for a miscellaneous circuit having a device with an
"N"-shape negative resistance curve.
Subclass:
572
Secondary emissive type:
This subclass is indented under subclass 568. Subject matter
which includes an electron space discharge device which
relies upon the phenomenon of the release of electrons from a
structure which has been impacted by other high-velocity
electrons.
SEE OR SEARCH CLASS:
330, Amplifiers, subclass 42 for amplifiers utilizing
secondary emission tubes.
331, Oscillators, subclass 133 for oscillatory circuits
utilizing a secondary emissive tube such as a dynatron.
Subclass:
573
Electron multiplier type:
This subclass is indented under subclass 572. Subject matter
wherein the secondary emissive type tube includes multiple
electrodes (i.e., dynodes) which attract electrons freed from
a light sensitive cathode and thereby increase the number of
flowing electrons.
SEE OR SEARCH THIS CLASS, SUBCLASS:
514 for miscellaneous light responsive circuits which do not
provide electron multiplication.
Subclass:
574
Utilizing a three or more electrode solid-state device:
This subclass is indented under subclass 524. Subject matter
wherein the nonlinear circuit includes at least one
solid-state device with more than two electrodes having a
particularly described feature.
SEE OR SEARCH CLASS:
257, Active Solid-State Device (e.g., Transistors,
Solid-State Diodes), appropriate subclass for transistors or
solid-state devices, per se.
Subclass:
575
Darlington connection:
This subclass is indented under subclass 574. Subject matter
wherein a nonlinear circuit includes a connection of two
similar transistors where their collectors are tied together
and the emitter of the first transistor is directly coupled
to the base of the second transistor and the emitter current
of the first transistor equals the base current of the second
transistor.
(1) Note. A Darlington connection is also called a
Darlington pair, double emitter-follower or beta-multiplier.
Subclass:
576
Complementary transistors:
This subclass is indented under subclass 574. Subject matter
wherein a nonlinear circuit includes two transistors that
have opposite conductivity (i.e., pnp and npn) and have
matching electrical characteristics.
SEE OR SEARCH THIS CLASS, SUBCLASS:
214 for bistable circuits including complementary
transistors.
Subclass:
577
Multiple emitter transistor:
This subclass is indented under subclass 574. Subject matter
wherein a circuit includes a three or more electrode
solid-state device which is a junction type bipolar
transistor having at least two emitter regions in addition to
the base and collector regions.
Subclass:
578
Multiple collector transistor:
This subclass is indented under subclass 574. Subject matter
wherein the circuit includes a three or more electrode
solid-state device which is a junction type bipolar
transistor having at least two collector regions in addition
to base and emitter regions.
Subclass:
579
Minority carrier storage:
This subclass is indented under subclass 574. Subject matter
wherein a concentration of minority carriers occurring at a
pn junction of a semiconductor is utilized, increased, or
avoided.
SEE OR SEARCH THIS CLASS, SUBCLASS:
585 for miscellaneous minority carrier storage diode
circuits.
Subclass:
580
Transistor breakdown device (e.g., avalanche, zener, punch
through, etc.):
This subclass is indented under subclass 574. Subject matter
including a transistor having a threshold voltage above which
the applied voltage must rise before a junction breakdown
occurs allowing a current to flow across the transistor
junction.
Subclass:
581
Field-effect transistor:
This subclass is indented under subclass 574. Subject matter
including a unipolar transistor in which current carriers are
injected at a source terminal and pass to a drain terminal
through a channel of semiconductor material whose
conductivity depends largely on an electric field applied to
the semiconductor from a control terminal (gate).
(1) Note. In a unipolar transistor, the source to drain
current involves only one type of charge carrier (i.e., holes
in a p-type material channel and electrons in an n-type
material channel).
(2) Note. Two types of FET structures are prevalent: (a)
an all-junction device, known as a junction FET or JFET
characterized by having heavily doped impurity regions of one
type (e.g., p-type material), known as gate regions, on both
sides of a second type semiconductor bar (e.g., n+ type
material) to form a pn junction, and (b) a device such as a
MOSFET/IGFET, consisting of a lightly doped substrate (e.g.,
p-type material) into which two highly doped regions (e.g.,
n+ type material) are diffused for forming source/drain
regions with the area therebetween becoming the channel for
current carriers (i.e., holes or electrons) and with a layer
of insulating material (e.g., SiO[subscrpt]2[end subscrpt])
grown over the channel surface for separating the channel
from a control (i.e., gate) electrode.
Subclass:
582
Four or more layer device (e.g., silicon-controlled
rectifier, etc.):
This subclass is indented under subclass 574. Subject matter
including a semiconductor device with four or more
alternating layers having different conductivities, for
example a pnpn device.
SEE OR SEARCH CLASS:
257, Active Solid-State Devices (e.g., Transistors,
Solid-State Diodes), appropriate subclasses for a
semiconductor structure, per se.
Subclass:
583
Utilizing two electrode solid-state device:
This subclass is indented under subclass 524. Subject matter
including a semiconductor device containing two structures
that emit or collect electrons or holes, or that control
their movements by an applied electrical field.
Subclass:
584
Breakdown diode (e.g., zener diode, avalanche diode, etc.):
This subclass is indented under subclass 583. Subject matter
including a diode circuit having a threshold voltage above
which the applied voltage must rise before the diode junction
breaks down allowing current flow across the diode pn
junction to rise suddenly.
Subclass:
585
Minority carrier storage diode (e.g., enhancement diode,
etc.):
This subclass is indented under subclass 583. Subject matter
including a diode wherein minority carriers which accumulate
at the junction when the diode is forward biased are suddenly
swept away after the back biasing increases to a certain
point.
SEE OR SEARCH THIS CLASS, SUBCLASS:
579 for a miscellaneous minority carrier storage transistor
circuit.
Subclass:
586
Capacitive diode:
This subclass is indented under subclass 583. Subject matter
including a voltage responsive diode whose capacitance varies
as a result of changes in the space charge at the pn
junction.
SEE OR SEARCH THIS CLASS, SUBCLASS:
194 for stable state circuits utilizing a capacitive diode.
302 for clock or pulse waveform generating utilizing a
storage diode.
Subclass:
587
Bridge circuit:
This subclass is indented under subclass 583. Subject matter
including four two-electrode solid-state devices with their
input and output terminals connected in a closed loop to form
a four arm network.
(1) Note. Bridge circuits may have another arm, called a
diagonal arm, which is connected across two adjacent arms of
the network, between an input terminal and an output
terminal.
SEE OR SEARCH THIS CLASS, SUBCLASS:
588 for a miscellaneous bridge circuit.
Subclass:
588
With bridge circuit:
This subclass is indented under subclass 524. Subject matter
including a circuit wherein four electrical elements have
their input and output terminals connected in a closed loop
to form a four arm network.
(1) Note. Bridge circuits may have another arm, called a
diagonal arm, which is connected across two adjacent arms of
the network, between an input terminal and an output
terminal.
SEE OR SEARCH THIS CLASS, SUBCLASS:
587 for two electrode solid-state device with bridge
circuit.
SEE OR SEARCH CLASS:
323, Electricity: Power Supply or Regulation Systems,
subclass 365 for Wheatstone bridges, in general.
324, Electricity: Measuring and Testing, 57 for impedance
measuring bridge systems and subclasses 98+ and 101 for
bridge-type electric meter systems.
330, Amplifiers, subclass 72, 76+, 146, and 175 for amplifier
networks utilizing bridge networks.
331, Oscillators, subclass 110 and 138+ for bridge-type
oscillator systems.
332, Modulators, subclass 172 for bridge-type amplitude
modulators.
333, Wave Transmission Lines and Networks, 117, 169, 170+,
and 197+ for passive type bridge systems.
Subclass:
589
With bootstrap circuit:
This subclass is indented under subclass 524. Subject matter
which achieves enhanced circuit linearity generally by a
particular signal boost feedback structure.
SEE OR SEARCH CLASS:
326, Electronic Digital Logic Circuitry, subclass 88 and 92
for logic circuits with bootstrapping.
330, Amplifiers, subclass 156 for amplifiers which use a
bootstrap coupling to the input circuit of the amplifier and
in which there is a linear relationship between the output
and the input.
Subclass:
590
With particular feedback:
This subclass is indented under subclass 524. Subject matter
wherein energy is transferred from the output of the circuit
device to an input thereof.
SEE OR SEARCH CLASS:
330, Amplifiers, subclass 75, 290, and 291+ for feedback
amplifiers.
Subclass:
591
Tube performs plural functions:
This subclass is indented under subclass 524. Subject matter
wherein a nonlinear circuit device includes an electron tube
which performs at least two independent operations either
simultaneously or selectively.
(1) Note. An example for this subclass is a circuit
including a tube which may be used alternatively as a
rectifier or a non-linear amplifier, etc.
SEE OR SEARCH THIS CLASS, SUBCLASS:
334 for a circuit which relates an output signal to an input
signal by a mathematical operation or function.
SEE OR SEARCH CLASS:
331, Oscillators, subclass 58 for free running oscillators
wherein the tube or tubes of the oscillator perform other
functions simultaneously with the oscillatory function and
subclass 59 for convertible oscillator systems (e.g.,
oscillator to amplifier, etc.).
Subclass:
592
With oscillation prevention:
This subclass is indented under subclass 524. Subject matter
wherein a particular circuit prevents undesired oscillation
or ringing.
SEE OR SEARCH THIS CLASS, SUBCLASS:
549 for a supply or bias source with hum prevention.
SEE OR SEARCH CLASS:
330, Amplifiers, subclass 149 for hum or noise bucking
systems.
331, Oscillators, subclass 105 for oscillators with
parasitic oscillation control or prevention means.
Subclass:
593
With distributed parameter circuit:
This subclass is indented under subclass 524. Subject matter
wherein a particular circuit is of the distributed network
type, the capacitance, inductance and resistance of which
cannot be isolated into separate lumped capacitors,
inductors, or resistors and wherein the time factor of
propagation of wave energy in the network is appreciable.
SEE OR SEARCH THIS CLASS, SUBCLASS:
123 for harmonic frequency conversion systems with
distributed parameter elements.
SEE OR SEARCH CLASS:
330, Amplifiers, particularly subclass 5, 43, 44+, 47, 49,
and 53+ for amplifiers with distributed parameter elements.
331, Oscillators, subclass 5, 6+, 79+, 86+, 93, and 96+ for
oscillators with distributed parameter elements.
333, Wave Transmission Lines and Networks, appropriate
subclasses for wave transmission networks of the long line
type.
Subclass:
594
With particular coupling or decoupling:
This subclass is indented under subclass 524. Subject matter
wherein a particular circuit includes an electrical
interaction between a source and an input to the system,
between the output of a first electrical device and the input
of another such device, or between the input of the system
and the output of the system.
SEE OR SEARCH THIS CLASS, SUBCLASS:
329 for amplitude limiting systems with tuned circuit.
531 for particular source of power or bias voltage with
filter or rectifier.
SEE OR SEARCH CLASS:
330, Amplifiers, 157 for plural stage amplifiers with
interstage coupling means, subclasses 185+ for input and
subclasses 192+ for output coupling networks.
331, Oscillators, 72 for oscillator circuits utilizing
electron coupled tube means and subclasses 74+ for
oscillators with particular output coupling network.
333, Wave Transmission Lines and Networks, subclass 3, 24,
109+, 117+, and 124+ for coupling networks comprised of
passive elements.
Subclass:
595
With particular connecting:
This subclass is indented under subclass 524. Subject matter
wherein a particular circuit includes a network in which
there exists a path, composed of branches of the network,
between every pair of terminals of the network.
(1) Note. Some examples of systems to be found in this
subclass are push-pull, push-push, direct, and parallel
connected networks.
Subclass:
596
Including oscillatory or shock-excited circuit:
This subclass is indented under subclass 524. Subject matter
wherein a particular circuit includes a circuit capable of
maintaining sustained oscillations or a resonant circuit
capable of oscillating freely upon having an impulse of
energy applied thereto.
SEE OR SEARCH THIS CLASS, SUBCLASS:
32 for pulse width selecting systems with shock excited
circuit.
100 for non-free running signal generation.
SEE OR SEARCH CLASS:
331, Oscillators, subclass 128 and 165+ for shock excited
resonant circuit oscillators.
Subclass:
597
With particular grid control:
This subclass is indented under subclass 524. Subject matter
wherein a particular circuit includes an impedance network
which is provided in the input circuit of a control grid of
an electron space discharge tube whereby the conductive state
of the tube depends upon the state of the impedance network.
SEE OR SEARCH CLASS:
313, Electric Lamp and Discharge Devices, 293 for a
discharge device with apertured electrode (e.g., grid)
between two other electrodes.
315, Electric Lamp and Discharge Devices: Systems,
appropriate subclasses for such discharge device systems as
those which control a discharge device as the ultimate load
therein.
330, Amplifiers, appropriate subclasses for grid controlled
tube amplifiers.
Subclass:
598
With particular tube structure:
This subclass is indented under subclass 524. Subject matter
wherein a particular circuit includes a space discharge
device of special tube construction or electrode
arrangement.
(1) Note. This subclass and the intended subclasses will
include structures of the tube wherein a plurality of groups
of electrodes are contained in a single envelope, provided
that there is one input circuit and one output circuit and
the entire assembly acts as a single tube.
(2) Note. For subject matter comprehending structural
features of electrical lamp and discharge devices with no
significant control circuit means, the search will extend to
Class 313, Electric Lamp and Discharge Devices. For subject
matter comprehending special types of electric lamp and space
discharge devices combined with control circuits whereby the
conductive condition of the device is determined and wherein
no load is included, the search will extend to Class 315,
Electric Lamp and Discharge Devices: Systems.
SEE OR SEARCH CLASS:
313, Electric Lamp and Discharge Devices, for the structure
of space discharge device, see (2) Note.
315, Electric Lamp and Discharge Devices: Systems, 3 and
32+ for combined tube and circuit element structure, see (2)
Note.
330, Amplifiers, subclass 3, 41, 42, 43, 44+, 47+, 49, and 64
for amplifier systems utilizing tubes of a particular
construction.
331, Oscillators, subclass 5, 6+, 79+, 86+, 103, 126+, and
184 for oscillator systems utilizing tubes of a particular
construction.
332, Modulators, 165 for modulator systems utilizing tubes
of a particular construction.
Subclass:
599
Vacuum tube type:
This subclass is indented under subclass 598. Subject matter
wherein a particular circuit includes a space discharge
device which consists of electrodes in an evacuated tube.
Subclass:
600
Beam tube structure:
This subclass is indented under subclass 599. Subject matter
including a space discharge device which contains and
controls a narrow electron stream.
SEE OR SEARCH THIS CLASS, SUBCLASS:
301 for rectangular or pulse waveform generation with
electron beam type tube.
SEE OR SEARCH CLASS:
250, Radiant Energy, subclass 281 for methods and apparatus
for the ionic separation or analysis of material (e.g., mass
spectrometer), subclass 306 for the inspection of solids or
liquids by charged particles (e.g., electron microscopes),
subclasses 440.1+ for irradiated object supports of the
charged particle inspection type, and subclasses 492.1+ for
the irradiation of objects or materials, generally.
313, Electric Lamp and Discharge Devices, subclass 62 for
cyclotron structure, subclasses 299, 359, and 364 for beam
tube structures, and subclasses 359.1+ for the structure of
positive ion accelerators.
315, Electric Lamp and Discharge Devices: Systems, subclass
3 for beam tube and circuit element structure.
Subclass:
601
Gas tube:
This subclass is indented under subclass 598. Subject matter
wherein a particular circuit includes a space discharge
device which consists of electrodes in a gas filled envelope
or tube.
Subclass:
602
With particular electrode arrangement:
This subclass is indented under subclass 601. Subject matter
wherein a gaseous discharge tube device includes a particular
electrode configuration.
SEE OR SEARCH CLASS:
313, Electric Lamp and Discharge Devices, 567 for electron
space discharge devices comprised of an envelope with gas or
vapor and which may have a particular electrode arrangement.
Subclass:
603
MISCELLANEOUS:
This subclass is indented under the class definition.
Subject matter not provided for in any of the preceding
subclasses.
Information Products Division -- Contacts
Questions regarding this report should be directed to:
U.S. Patent and Trademark Office
Information Products Division
PK3- Suite 441
Washington, DC 20231
tel: (703) 306-2600
FAX: (703) 306-2737
email: oeip@uspto.gov
Last Modified: 6 October 2000