CPC Definition - Subclass H03K

Last Updated Version: 2020.02
PULSE TECHNIQUE (measuring pulse characteristics G01R; modulating sinusoidal oscillations with pulses H03C; transmission of digital information H04L; discriminator circuits detecting phase difference between two signals by counting or integrating cycles of oscillation H03D 3/04; automatic control, starting, synchronisation or stabilisation of generators of electronic oscillations or pulses where the type of generator is irrelevant or unspecified H03L; coding, decoding or code conversion, in general H03M)
Definition statement

This place covers:

  • methods, circuits, devices, or apparatus using active elements operating in a discontinuous or switching manner for generating, shaping and manipulating pulse signals
  • generating stepped pulses or pulses having an essentially finite slope
  • producing pulses by distorting or combining sinusoidal waveforms
  • shaping, amplifying and otherwise manipulating pulse signals
  • modulating pulses with a continuously variable modulating signal, and demodulating pulses which have been so modulated
  • transforming types of pulse modulation
  • electronic switching not involving contact-making and breaking
  • logic circuits handling electric pulses
  • counting pulses, pulse counters and frequency dividers, pulse counters with step-by-step integration and static storage, pulse counters in which pulses are continuously circulated, pulse counters comprising multi-stable elements
Relationships with other classification places

The modulation and demodulation of pulse trains, for example in Pulse Width Modulation circuits, is covered in subclass H03K.

The modulation and demodulation of sinusoidal signals, for example in AM and FM broadcasting, is covered in subclasses H03C and H03D.

The modulation by digital signals of the frequency, phase or amplitude of sinusoidal carrier, or carriers, is covered in subclass H04L. Quadrature (I-Q) modulation systems used for the transmission of digital information, e.g. QAM, the effect of which is to modulate a carrier in both amplitude and phase (often in discrete steps, which may be illustrated as a 'constellation' of points, each point representing a pair of carrier amplitude and phase values), are covered in subclass H04L.

Analogue quadrature modulation used in the NTSC and PAL colour television systems (where the I and Q signals representing colour difference values are substantially continuously variable), is covered in H04N.

References
Limiting references

This place does not cover:

measuring pulse characteristic

G01R

measuring electrical signals (to get a value)

G01R 17/00- G01R 29/00

testing electrical circuits

G01R 31/00

Modulating sinusoidal oscillations with pulses

H03C

Demodulation or transference of signals modulated on a sinusoidal carrier

H03D

Automatic control, starting, synchronizing or stabilization of generators of electronic oscillations or pulses where the type of generator is irrelevant or unspecified

H03L

coding, decoding or code conversion in general

H03M

Transmission of digital information; modulated carrier systems

H04L, H04L 27/00

Informative references

Attention is drawn to the following places, which may be of interest for search:

Counting mechanisms

G06M

Information storage based on relative movement between record

G11B, G11C

Sample and hold arrangements in electric analogue stores

G11C 27/02

Electric Switches; Relays; Selectors; Emergency protective devices

H01H

Apparatus for conversion of electric power

H02M

Generation of oscillations by circuits employing active elements which operate in a non-switching manner

H03B

Special rules of classification

In this subclass, where the claims of a patent document are not limited to a specific circuit element, the document is classified at least according to the elements described in the described embodiment.

Glossary of terms

In this place, the following terms or expressions are used with the meaning indicated:

Differential

really means differential, not just complementary, i.e. two signals with an inverter in between are not differential

'continuously-variable' modulating signal

Analogue signals or signals that comprise a number of discrete levels, such as signals produced by counting circuits.

Circuits for generating electric pulses; Monostable, bistable or multistable circuits (H03K 4/00 takes precedence; for digital function generators in computers G06F 1/02)
Definition statement

This place covers:

  • Latches and flip-flops;
  • Non-linear (switching) oscillators;
  • Latching level shifters.
References
Limiting references

This place does not cover:

Generating pulses having essentially a finite slope or stepped portions

H03K 4/00

Digital function generators

G06F 1/02

Generating or distributing clock signals or signals derived directly therefrom

G06F 1/04

Application-oriented references

Examples of places where the subject matter of this place is covered when specially adapted, used for a particular purpose, or incorporated in a larger system:

Latches used in scan test of integrated circuits

G01R 31/318541

Latches and flip-flops used as static stores in semiconductor memories

G11C 11/41

Power pulse generators for driving lasers

H01S 5/42

Voltage- and current controlled oscillators

H03L 7/0995

Special rules of classification

Latching level shifters should be classified in the corresponding bistable circuit subgroups of this main group.

Generating pulses having essentially a finite slope or stepped portions
Definition statement

This place covers:

  • Relaxation oscillators.
  • Switched-capacitor oscillators
  • Ramp and sawtooth generators.
Relationships with other classification places

Multivibrators generating pulse signals other than finite-sloped or staircase signals should be classified in H03K 3/00.

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Generation of supply voltages in combination with electron beam deflection in television scanning systems

H04N 3/18

Special rules of classification

H03K 4/026: Digital generators followed by a digital-to-analog converter to produce analogue output stepped signals.

Manipulating of pulses not covered by one of the other main groups of this subclass (circuits with regenerative action H03K 3/00, H03K 4/00; by the use of non-linear magnetic or dielectric devices H03K 3/45)
References
Limiting references

This place does not cover:

circuits with regenerative action

H03K 3/00, H03K 4/00

by the use of non-linear magnetic or dielectric devices

H03K 3/45

Glossary of terms

In this place, the following terms or expressions are used with the meaning indicated:

Regenerative action

internal or external positive feed-back.

Delay line

transmission line

{Changing the frequency (modulating pulses H03K 7/00; frequency dividers H03K 21/00 - H03K 29/00; additive or subtractive mixing of two pulse rates into one G06F 7/605; pulse rate dividers G06F 7/68)}
Definition statement

This place covers:

Mostly pulse rate multiply by 2 circuits based on delaying and combining.

References
Limiting references

This place does not cover:

Pulse frequency multipliers

G06F 7/68

Changing the DC level (reinsertion of dc component of a television signal H04N 5/16)
References
Limiting references

This place does not cover:

reinsertion of dc component of a television signal

H04N 5/16

Shaping pulses (discrimination against noise or interference H03K 5/125)
References
Informative references

Attention is drawn to the following places, which may be of interest for search:

For reducing generated interference

H03K 17/16, H03K 19/00346

For impedance matching

H03K 19/00, H04L 25/00

For reducing power consumption

H03K 19/0008

For baseband data transmission

H04L 25/0286, H04L 25/03834

by increasing duration; by decreasing duration
Definition statement

This place covers:

Also used for slew rate control circuits.

by the use of delay lines or other analogue delay elements
Definition statement

This place covers:

For instance circuits for staggering turn on signals.

{using dispersive delay lines}
Definition statement

This place covers:

Delay lines having propagation speed depending on input frequency.

by limiting; by thresholding; by slicing, i.e. combined limiting and thresholding (H03K 5/07 takes precedence; comparing one pulse with another H03K 5/22; providing a determined threshold for switching H03K 17/30)
Definition statement

This place covers:

Clamping circuits in general

References
Limiting references

This place does not cover:

For details of threshold comparators

H03K 5/24, G01R 19/165, H03F 3/45

Clamping for ESD protection

H01L 27/0251

{modified by switching, e.g. by a periodic signal or by a signal in synchronism with the transitions of the output signal}
Definition statement

This place covers:

The value of the threshold is generated by feedback AND the value is modified by switching.

{generated by feedback}
Definition statement

This place covers:

i.e. the value of the threshold is generated by feedback.

{modified by switching, e.g. by a periodic signal or by a signal in synchronism with the transitions of the output signal}
Definition statement

This place covers:

The switching only relating to the switching instants.

References
Limiting references

This place does not cover:

If the value of the threshold being switched is generated by feedback

H03K 5/086

If the value is generated by feedback AND modified by switching

H03K 5/088

by steepening leading or trailing edges
Definition statement

This place covers:

Mostly used for pulse compression circuits using non-linear transmission lines having propagation speed depending on input amplitude, such as diode loaded transmission lines, to steepen one of the pulse edges and slow the other.

References
Limiting references

This place does not cover:

Changing the slew rate of leading and/or falling pulses in general

H03K 5/01, H03K 5/04, H03K 5/06

Accelerating switching

H03K 17/04, H03K 19/01

Suppression or limitation of noise or interference (specially adapted for transmission systems H04B 15/00, H04L 25/08)
Definition statement

This place covers:

Mostly suppression of glitches in binary signals by delay and subsequent logic combination with the original signal.

Some documents (often also classified in H03K 5/156 or H03K 5/1565) relate to phase noise suppression in (interpolated) clock signals.

References
Limiting references

This place does not cover:

Suppressing noise by slew rate control

H03K 5/04, H03K 17/16, H03K 19/00346

Special rules of classification

For glitches produced when switching from one clock signal to another G06F 1/08 takes precedence.

Arrangements having a single output and transforming input signals into pulses delivered at desired time intervals {(measuring time intervals using electronic timing, e.g. counting means G04F 1/005)}
Definition statement

This place covers:

  • Mainly used for delay circuits but also for some generic pulse circuits having multiple inputs and a single output
  • Phase interpolation
References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Measuring time intervals using electronic timing, e.g. counting means

G04F 1/00

Special rules of classification

Additional aspects are classified as follows

Phase interpolation circuits H03K 2005/00052

Digitally controlled
Special rules of classification

Also classify in: H03K 2005/00058 (controlled by a digital setting)

by the use of time reference signals, e.g. clock signals
Definition statement

This place covers:

  • Synchronising a signal to a clock signal
  • Using a clock signal as a reference for controlling a delay, e.g. synchronous mirror delay circuits (SMDs), in which a detected number of gates in a first delay line - through which a signal edge propagates in a predetermined time defined by the reference clock - is used for controlling the number of delay elements in a second delay line for compensation.
References
Limiting references

This place does not cover:

Synchronisation of pulses generated from circuits classified in H03K 4/00

H03K 4/90

Synchronisation of clock signals in data processing equipment

G06F 1/12

Clocked shift registers

G11C 19/00

PLL, DLL

H03L 7/08

Synchronisation in TDM systems

H04J 3/00

Synchronising data receiver with transmitter, e.g. using clock data recovery

H04L 7/00

Arrangements in which pulses are delivered at different times at several outputs, i.e. pulse distributors (distributing, switching or gating arrangements H03K 17/00)
References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Distributing clock signals in data processing equipment:

G06F 1/10.

{with asynchronously driven series connected output stages}
Definition statement

This place covers:

Tapped arrangement

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

using a chain of active delay devices

H03K 5/133

{with parallel driven output stages; with synchronously driven series connected output stages}
Definition statement

This place covers:

Pulse distributor with output stages driven more or less synchronously either in parallel in a tree-like structure OR sequentially with shift register like structure.

References
Limiting references

This place does not cover:

Distributing clock signals in data processing equipment

G06F 1/10

{using devices arranged in a shift register}
References
Limiting references

This place does not cover:

Shift registers per se

G11C 19/00

with two complementary outputs
Definition statement

This place covers:

Providing simultaneous switching of two complementary signals.

{non-overlapping}
Definition statement

This place covers:

In particular suitable for preventing simultaneous conduction in push pull stages.

References
Limiting references

This place does not cover:

Protecting switching stages against overload by arrangements in the control circuit

H03K 17/0812

Complementarily driven MOS switches

H03K 17/6871

Preventing simultaneous conduction in DC/DC converters

H02M 1/38

Arrangements in which a pulse is delivered at the instant when a predetermined characteristic of an input signal is present or at a fixed time interval after this instant (switching at zero crossing H03K 17/13 {; measuring characteristics of individual pulses G01R 29/02})
References
Informative references

Attention is drawn to the following places, which may be of interest for search:

indicating of signal events

G01R

Peak detectors (measuring characteristics of individual pulses G01R 29/02)
Definition statement

This place covers:

Peak instant detectors only

References
Limiting references

This place does not cover:

Measuring characteristics of individual pulses

G01R 29/02

{the output pulses having a constant duty cycle}
Definition statement

This place covers:

Also contains ccts for suppressing jitter and phase noise in pulse signals.

References
Limiting references

This place does not cover:

Generators (i.e. circuits not having a signal input) with duty cycle adjustment

H03K 3/017

Duty cycle modulation schemes

H03K 7/08

Applications of delay lines not covered by the preceding subgroups
References
Limiting references

This place does not cover:

Transversal filters

H03H 15/00

Monitoring patterns of pulse trains (indicating amplitude G01R 19/00; indicating frequency G01R 23/00; measuring characteristics of individual pulses G01R 29/02)
Definition statement

This place covers:

Detecting presence of valid pulse signal, e.g monitoring amplitude and/or frequency of pulse signal.

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Distribution of clock signals

G01F 1/10

Measuring electrical variables

G01R

the characteristic being amplitude
Definition statement

This place covers:

Pulse comparators.

References
Limiting references

This place does not cover:

Comparators using latches or having hysteresis

H03K 3/00, H03F 1/38

Thresholding or clamping

H03K 5/08

DC comparators

G01R 19/0038

Indicating signal level

G01R 19/165

Current (mirror) comparators: Only the ones giving full swing outputs classified here

G05F 3/26

Circuits comparing digital numbers

G06F 7/02

Sense amplifiers

G11C

Manipulating pulses having a finite slope and not covered by one of the other main groups of this subclass (circuits with regenerative action H03K 4/00)
Definition statement

This place covers:

Slew rate correction in ramp or triangular waveform generators..

References
Limiting references

This place does not cover:

Modulating pulses with a continuously-variable modulating signal
Definition statement

This place covers:

Continuous modulating signal meaning (quasi-)analog.

Only basic schemes for modulating one or more pulse characteristics are classsified here. See also application fields.

\

References
Limiting references

This place does not cover:

Discrete pulse modulation

H04L 25/00, G06F 1/025

Position modulation, i.e. PPM
References
Limiting references

This place does not cover:

Impulse radio, UWB signals

H04B 1/69

Frequency or rate modulation, i.e. PFM or PRM
References
Limiting references

This place does not cover:

Random signal generators

H03K 3/84

Random number generators

G06F1/58R

Noise generators

H03B

For spread spectrum clock signals

H04B 15/04

Duration or width modulation {Duty cycle modulation}
Definition statement

This place covers:

Basic modulation concept such as comparing voltage to (quasi-)analog ramp signal.

References
Limiting references

This place does not cover:

For signal generators

G06F 1/025

switch mode controllers

H02P

Class D amplifiers

H03F 3/217, H02M

D/A converters

H03M

For data signals

H04L 25/4902

Demodulating pulses which have been modulated with a continuously-variable signal
Definition statement

This place covers:

Only for documents not showing the modulator or where the demodulator is clearly the main aspect.

Electronic switching or gating, i.e. not by contact-making and –breaking (gated amplifiers H03F 3/72; switching arrangements for exchange systems using static devices H04Q 3/52)
Definition statement

This place covers:

  • Composite switches: multiple types of transistors form a switching unit e.g. IGBT
  • Output circuit: drain-source or collector-emitter path including load
  • Input circuit: means connected to gate- or base-connection
  • Feedback from the output to the input circuit: does not include e.g. common source or emitter connections as a voltage reference
References
Limiting references

This place does not cover:

gated amplifiers

H03F 3/72

switching arrangements for exchange systems using static devices

H04Q 3/52

Informative references

Attention is drawn to the following places, which may be of interest for search:

In electric printing, selection of a stylus or auxiliary electrode to be supplied with current for transfer to printing or impression transfer material

B41J 2/405

Switching or interrupting devices in waveguides

H01P

{Switching arrangements with several input- or output terminals (code converters H03M 5/00, H03M 7/00)}
Definition statement

This place covers:

General multiplexers (block diagrams)

Special rules of classification

More detailed structures are classified as follows:

bipolar transistor based mux circuits: H03K 17/62 and subgroups

field-effect transistor based mux circuits: H03K 17/693

diode based mux circuits: H03K 17/76

Modifications for accelerating switching
Definition statement

This place covers:

Acceleration means

References
Limiting references

This place does not cover:

the mere speed gain one gets by using a different material, type of transistor, etc

H03K 17/51

{in composite switches}
Definition statement

This place covers:

Composite switches -> mainly IGBTs

Modifications for ensuring a fully conducting state
References
Limiting references

This place does not cover:

Diode replacement circuits

H03K 17/30

Modifications for protecting switching circuit against overcurrent or overvoltage
References
Limiting references

This place does not cover:

For testing etc. of semiconductors

G01R 31/26

Safety devices eventually

G05B 9/02, F16P 3/00, G05B 19/042

Special rules of classification

Protection circuits for protecting the switch go in here, those protecting the load go in H02H 3/00 (remember to distribute it in classification). We will therefore in almost any case have to search in there as well.

Any document with a switch and a temperature detector is classified in H03K 2017/0806.

by measures taken in the control circuit
References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Circuits whose output signals could be used for x-bar current prevention in a half-bridge, i.e. non-overlapping signals

H03K 5/1515

by measures taken in the output circuit
References
Informative references

Attention is drawn to the following places, which may be of interest for search:

For solid state switches which are protected by having a mechanical switch (MEMS) in series

H01H 9/548

Modifications for increasing the maximum permissible switched voltage
References
Limiting references

This place does not cover:

by merely different types of transistors

H01L

Modifications for increasing the maximum permissible switched current
References
Limiting references

This place does not cover:

by merely different types of transistors

H01L

Modifications for switching at zero crossing (generating an impulse at zero crossing H03K 5/1536)
References
Limiting references

This place does not cover:

generating an impulse at zero crossing

H03K 5/1536

Modifications for eliminating interference voltages or currents
Definition statement

This place covers:

Caused by the switching, e.g. reducing switching noise

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

means for preventing simultaneous conduction

H03K 5/1515, H02M 1/38

{Soft switching}
Special rules of classification

Soft switching aspects are also classified in H02H 9/001

{Soft switching}
Special rules of classification

Soft switching aspects are also classified in H02H 9/001

Modifications for indicating state of switch
Definition statement

This place covers:

Any kind of state, i.e. not only the switching state but also e.g. if short-circuited, how many times overloaded so far etc. etc.

indicating -> display or generation of feedback signals to higher entity etc.

Glossary of terms

In this place, the following terms or expressions are used with the meaning indicated:

Indicating

display or generation of feedback signals e.g. to a higher entity etc...

Modifications for ensuring a predetermined initial state when the supply voltage has been applied (bi-stable generators H03K 3/12)
Definition statement

This place covers:

Merely power-on-reset circuits of any kind

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Arrangements for measuring currents or voltages Indicating that current or voltage is either above or below a predetermined value

G01R 19/165

Resetting means

G06F 1/24, G06F 1/26

Storing the actual state when the supply voltage fails
References
Informative references

Attention is drawn to the following places, which may be of interest for search:

latches for opamps or comparator

H03K 3/02335

logic circuit

H03K 3/0375

bipolar transistor

H03K 3/2865

field-effect transistor

H03K 3/356008

Time-programme switches providing a choice of time-intervals for executing more than one switching action and automatically terminating their operation after the programme is completed (electronic clocks comprising means to be operated at preselected times or after preselected time-intervals G04G 15/00)
Definition statement

This place covers:

Also Christmas tree type pre-programmable plugs

Modifications for providing a predetermined threshold before switching (shaping pulses by thresholding H03K 5/08 {; for logic circuits H03K 19/0021})
Definition statement

This place covers:

Keeping an absolute switching threshold or switching at a threshold different from the threshold of the switching element

Special rules of classification

Diode replacement Transistors can also be classified in H03K 17/06 or H03K 17/063.

the devices being bipolar transistors (bipolar transistors having four or more electrodes H03K 17/72)
References
Limiting references

This place does not cover:

bipolar transistors having four or more electrodes

H03K 17/72

Switching arrangements with several input- or output-terminals, e.g. multiplexers, distributors (logic circuits H03K 19/00; code converters H03M 5/00, H03M 7/00)
References
Limiting references

This place does not cover:

logic circuits

H03K 19/00

Code converters

H03M 5/00, H03M 7/00

characterised by the way in which the control signals are generated
Definition statement

This place covers:

Some detection methods which are not to be found elsewhere & details related to the operation of generic sensors.

This class contains different sensing priciples:

microwave

RF energy sensor

ultrasonic

infrasonic

acoustically activated

temperature activated

Power supply related documents are found here and in H03K 17/945 if for generic sensor. H03K 17/951 is for power supply for non-generic sensor, even if not magnetic.

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Keyboards for special applications: see the relevant places

B41J, G06F 3/023, H04L 15/00, H04L 17/00, H04M 1/00

Structural details of switches, relays or selectors and emergency protective devices, their contact and mechanical operating arrangements; operation by mechanical forces or by a change of physical condition; time programming switches and switches providing a selected number of operations of the contacts

H01H

Glossary of terms

In this place, the following terms or expressions are used with the meaning indicated:

RF energy sensor

e.g. to sense absorption of RF energy by a resonant tank circuit at predetermined frequencies, where the tank circuit corresponds to each keybutton. An emitter device emits energy in a path of tank circuit towards the RF energy sensor. A determination device determines a depression state of the keybuttons in accordance with absorption

{using an optical detector (H03K 17/968 takes precedence)}
References
Limiting references

This place does not cover:

Detection only, no switching

G01S 17/04

Optical scanner

G02B26/08M4B

Photocouplers

Informative references

Attention is drawn to the following places, which may be of interest for search:

Light barriers and using reflection on object

G01V 8/00, G01S 17/04

Proximity switches (H03K 17/96 takes precedence {; proximity fuzes F42C 13/00; detecting masses or objects, e.g. by using a magnetic or optical detector G01V, e.g. G01V 3/00, G01V 8/10})
Definition statement

This place covers:

Constructional details, housings for sensors, network of proximity sensors, programming of proximity switches

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Explicitly for magnetic proximity sensors

H03K 17/9505

Housings for sensors

G01D 11/245

{Measures for increasing reliability}
Definition statement

This place covers:

Temperature compensation, self-test, redundant sensors, security switches (using codes), passive and active responders, protection against noise and interference

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Transponders in proximity switches

H03K 17/9522, H03K 17/9525

Passive transponders,

G06K 7/086, G01D 5/2066

{Measures for supplying operating voltage to the detector circuit}
Definition statement

This place covers:

For practical purposes also power supply details of non-magnetic touch sensors.

{using non-linear magnetic devices}
Definition statement

This place covers:

Also bistable magnetic elements (Barkhausen effect, Wiegand effect, Matteucci effect).

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Electronic switching or gating using a magnetic movable element

H03K 17/97

Wiegand effect

G01P

Barkhausen effect

G01P 3/488

{using galvanomagnetic devices}
Definition statement

This place covers:

Hall effect sensors, magnetoresistance.

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

If target is magnetic:

H03K 17/97

Hall effect:

G01R 33/07, G01D 5/145

Magnetoresistance:

G01R 33/09

{using inductive coils}
Special rules of classification

H03K 17/9537 takes precedence.

{in a resonant circuit}
Definition statement

This place covers:

LC-resonant circuit in general (e.g. signal is interrogation pulse, usually generating damped or decaying oscillations)

{forming part of an oscillator}
Definition statement

This place covers:

LC-resonant circuit forming part of oscillator; the variable parameter is undetermined

{with variable frequency}
Definition statement

This place covers:

LC-resonant circuit forming part of oscillator; the variable parameter is oscillation frequency

{with variable amplitude}
Definition statement

This place covers:

LC-resonant circuit forming part of oscillator; the variable parameter is oscillation amplitude

using a capacitive detector
Definition statement

This place covers:

Charge transfer, phase comparison, frequency shift, resistance-capacitance timing circuits

References
Limiting references

This place does not cover:

Electrically operated windows or roofs

E05F 15/00

Distance measurement

G01D 5/24

Informative references

Attention is drawn to the following places, which may be of interest for search:

Capacitive touch switches

H03K 17/962

Detection of varying capacitance

G01D 5/24

Housings for sensors

G01D 11/00

Measuring capacitance

G01R 27/2605

Touch switches (specially adapted for electronic time-pieces with no moving parts G04G 21/08)
Definition statement

This place covers:

Constructional details, detection principles, simulation of slider, key illumination details

References
Limiting references

This place does not cover:

specially adapted for electronic time-pieces with no moving parts

G04G 21/08

{Capacitive touch switches}
Definition statement

This place covers:

Detection principle

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Measuring capacitance

G01R 27/2605

{using a plurality of detectors, e.g. keyboard}
References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Digitisers by capacitive means

G06F 3/044

{using a force resistance transducer}
Definition statement

This place covers:

Means for interpreting an external force as a variable resistance (e.g. strain gauges)

References
Limiting references

This place does not cover:

Resistive touch switches

H03K 17/9645

Informative references

Attention is drawn to the following places, which may be of interest for search:

Measuring force or stress in general

G01L 1/20

Measuring force or stress using distributed sensing elements

G01L 1/205

Digitisers using force sensing means

G06F 3/0414

Adjustable resistors adjustable by mechanical pressure of force

H01C 10/10

Adjustable resistors by using means responding to magnetic or electric fields, e.g. by addition of magnetisable or piezoelectric particles to the resistive material

H01C 10/103

Adjustable resistors on resistive material dispersed in an elastic material

H01C 10/106

Adjustable by changing surface pressure between resistive masses or resistive and conductive masses

H01C 10/12

Switches with contacts carried by or formed from layers in a multilayer structure, e.g. membrane switches

H01H 13/702

Switches characterised by the material of the contacts, e.g. conductive polymers

H01H 13/785

{Optical touch switches}
Definition statement

This place covers:

ONLY documents which disclose reflection on a permanent interface surface

{using a plurality of detectors, e.g. keyboard}
Definition statement

This place covers:

Simulation of slider, in combination with display

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Digitisers by opto-electronic means

G06F 3/042

{using a light guide}
Definition statement

This place covers:

With deformation of the light guide

Glossary of terms

In this place, the following terms or expressions are used with the meaning indicated:

Touch

Deformation

{Resistive touch switches}
Definition statement

This place covers:

An object (e.g. finger) provides path for current

Switches controlled by moving an element forming part of the switch
Definition statement

This place covers:

Tactile feedback, illuminated, rotary, ...

References
Limiting references

This place does not cover:

Joysticks with analog output

G05G 9/047

using opto-electronic devices
References
Limiting references

This place does not cover:

Optical rotary encoders per se

G01D 5/3473

having a plurality of control members, e.g. keyboard
References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Coding in connection with keyboards or like devices using opto-electronic means

H03M211/26

using a magnetic movable element
Definition statement

This place covers:

Type of magnetic sensor: inductance, hall sensor, magnetoresistance

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Hall sensors

G01D 5/145

using a capacitive movable element
Definition statement

This place covers:

The movable part is an electrode forming part of the switch or the dielectric

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Mechanical means for transferring the output of a sensing member by varying capacitance

G01D 5/24

Logic circuits, i.e. having at least two inputs acting on one output (circuits for computer systems using fuzzy logic G06N 7/02); Inverting circuits
Definition statement

This place covers:

Circuits having at least two inputs acting on one output inverting circuits or buffers.

Relationships with other classification places

When a circuit is used or adapted for switching a load, it is classified in H03K 17/00. When it is used/adapted for driving a logic circuit (e.g. output buffer), it goes to H03K 19/00.

References
Limiting references

This place does not cover:

circuits for computer systems using fuzzy logic

G06N 7/02

Informative references

Attention is drawn to the following places, which may be of interest for search:

Nanotechnology logic

B82Y 10/00

Special rules of classification

The groups H03K 19/00369 take precedence over H03K 19/0005

H03K 19/003: Circuits for increasing the reliability, not for notifying the user that a failure took place

H03K 19/00323: Skew compensation

H03K 19/00346: Slope control, slew rate adaptation

H03K 19/007: Circuits in this class go, when they fail, to a safe state. They do not notify the user of a failure

H03K 19/01 covers accelerating switching in logic circuits and should not be confused with H03K 17/04 which covers accelerating the switching of a switch

H03K 19/177: Field Programmable Gate Arrays (FPGA).

Details of pulse counters or frequency dividers {(number-of-one counters G06F 7/607)}
Definition statement

This place covers:

Details of logic circuits having electric(digital) pulses as input signals and either counting incoming pulses or producing an output pulse stream based on the incoming pulse stream having a modified pulse repeating period.

References
Limiting references

This place does not cover:

Changing Frequency

H03K 5/00006

High Security Counting

G01C 22/02

Measuring Pulse Width Time

G01R 29/00

Coincidence Detection

G01T1/72

Non-integer Counting and Performing Operations by counting

G06F 7/60

Member-of-one (population) Counter

G06F 7/607

Binary Multiplication andPulse rate divider

G06F 7/62 - G06F 7/68

PLLs including Dividers

H03B, H03L

Input circuits
Definition statement

This place covers:

Special logic at input for pulse treatment e.g. pulse shaping

Illustrative examples of subject matter classified in this group:

media0.jpg

Figure taken from DE3842874

Output circuits
Definition statement

This place covers:

Special logic at register outputs e.g. for a counter value dependent reset.

media1.jpg

Figure taken from JP57199337

Circuits for carrying over pulses between successive decades
Definition statement

This place covers:

Logic counter having multiple counting stages including a carry over bit between stages.

media2.jpg

Figure taken from US5,946,369

Circuits for visual indication of the result
Definition statement

This place covers:

Logic for representing the result to a user.

media3.jpg

Figure taken from DE3031612

Starting, stopping or resetting the counter (counters with a base other than a power of two H03K 23/48, H03K 23/66)
Definition statement

This place covers:

Logic for influencing the counter status.

media4.jpg

Figure taken from EP0471390.

Monitoring; Error detection; Preventing or correcting improper counter operation
Definition statement

This place covers:

Monitoring whether an error occured during the counting process (not the process producing the pulses)

media5.jpg

Figure taken from DE2550177

Pulse counters comprising counting chains; Frequency dividers comprising counting chains (H03K 29/00 takes precedence)
Definition statement

This place covers:

Logic for digital counting chains used in pulse counters or frequency dividers

{using elements not covered by groups H03K 23/002 and H03K 23/74 - H03K 23/84}
Definition statement

This place covers:

Other elements as complementary IGFET's, electrically-ignited compounds e.g. pyrotechnical static relays

{Counters counting in a non-natural counting order, e.g. random counters}
Definition statement

This place covers:

Detailed counting encoding scheme.

Gating or clocking signals applied to all stages, i.e. synchronous counters {(H03K 23/74 - H03K 23/84 take precedence)}
Definition statement

This place covers:

Details regarding the clock used for triggering the counting of incoming pulses

Gating or clocking signals not applied to all stages, i.e. asynchronous counters (H03K 23/74 - H03K 23/84 take precedence)
Definition statement

This place covers:

Counter with a "rippling" trigger pulse form stage to stage - asynchronous counters.

with a base or radix other than a power of two (H03K 23/40 - H03K 23/62 take precedence)
Definition statement

This place covers:

Variable counting base, non-integer or odd-number counters.

Pulse counters with step-by-step integration and static storage; Analogous frequency dividers
Definition statement

This place covers:

Static storage type counters - e.g. capacitive type

media6.jpg

Figure taken from EP0916188

Pulse counters in which pulses are continuously circulated in a closed loop; Analogous frequency dividers (feedback shift register counters H03K 23/54)
Definition statement

This place covers:

media7.jpg

Figure taken from GB2008296.

Pulse counters comprising multi-stable elements, e.g. for ternary scale, for decimal scale; Analogous frequency dividers
Definition statement

This place covers:

A triggering pulse is generated in response to each input signal to be counted. The triggering pulse is applied to the device to change the voltage across the device. The voltage across the device is output as an indication of the number of received input signals. The device may be a resonant tunnelling diode with multiple peaks in its current versus voltage characteristic. The device may be a resonant tunnelling diode with multiple peaks in its current versus voltage characteristic.

media8.jpg

Figure taken from US 5,033,069