CPC Definition - Subclass H03L
This place covers:
Automatic control circuits for generators of electronic oscillations or pulses; starting, synchronization, or stabilization circuits for generators where the type of generator is irrelevant or unspecified.
This place does not cover:
Generation of oscillations |
Attention is drawn to the following places, which may be of interest for search:
In this place, the following terms or expressions are used with the meaning indicated:
automatic control | covers only closed loop systems |
This place covers:
Stabilisation of generator output against variations caused by environmental variations such as temperature, process variations when the generator is (partly) integrated on an electronic chip, aging of the components constituting the generator.
Attention is drawn to the following places, which may be of interest for search:
Against variations of temperature only | |
Automatic control | |
Modifications of generator, of oscillations using amplifier with regenerative feedback from output to input, to compensate for variations in physical values. | |
Modifications of generator, for generating electric pulses, to compensate for variations in physical values. |
This place covers:
Said distributed capacitances and inductances could be also delay lines, microstrips, and the like.
This place covers:
All devices having a variable capacitance e.g. Junction capacitors, MOS-capacitors, and the like.
This place covers:
also ovens for maintaining temperature constant
This place covers:
Arrangements for automatic controlling the output level/amplitude of the generator. The output of the generator could be a voltage, current or power.
Control of voltage, current or power wherein the generators are not generators for electronic oscillations or pulses, e.g. level shifts, power management, power supply regulators, automatic transmission power control, are not classified in H03L.
This place covers:
Arrangements for automatic controlling the output power level of the generator.
This place covers:
- Automatic control of the frequency or phase of the output of the generator;
- Synchronisation.
This place covers:
All means for converting the frequency to any of voltage, current or digital signal e.g. frequency-to-voltage converter, frequency-to-current converter, frequency-to-digital converter.
This place covers:
Distributed capacitances and inductances could be also delay lines, microstrips, and the like.
This place covers:
The reference signal is a frequency reference signal including constant frequency signal, data signal, and the like.
This place does not cover:
Modulation signal (e.g. US2008032649) | |
Modulated signal (e.g. US5625319) |
This place covers:
Using several loops, each loop having each its own controlled oscillator and/or phase shifter.
Attention is drawn to the following places, which may be of interest for search:
Using at least two phase detectors or a frequency and phase detector in the loop | |
Indirect frequency synthesis using more than one loop |
This place covers:
the "loop" meaning a Phase-locked loop (PLL) or a Delay-locked loop (DLL).
This place covers:
Recovery circuit for recovering the reference signal from the input signal, e.g. data signal.
Attention is drawn to the following places, which may be of interest for search:
Synchronisation of receiver with transmitter using the transitions of the received signal to control the phase of the synchronising-signal-generating means, e.g. using a phase-locked loop |
DCR or CDR | data/clock or clock/data recovery |
This place covers:
Controlled phase shifter in the loop e.g. delay element, phase selector, phase interpolator, and the like.
This subgroup does not include additional phase shifter outside the loop e.g. in the reference path or in the output path.
This place covers:
Delay-locked loops.
This place covers:
Controlled phase shifter which is digitally controlled e.g. by a register and/or an up-down counter.
This place covers:
Reference signal being additionally directly applied to the controlled oscillator in the loop.
Attention is drawn to the following places, which may be of interest for search:
Direct frequency synchronisation without loop |
This place covers:
- Frequency or phase detectors generating an up-down output pulse signal at a single terminal, e.g. an EXOR gate.
- Frequency or phase detectors comprising a time-to-digital converter (TDC).
This place does not cover:
Details of the phase-locked loop for assuring initial synchronisation or for broadening the capture range | |
Circuits for comparing the phase or frequency of two mutually-independent oscillations |
Attention is drawn to the following places, which may be of interest for search:
Demodulation of angle-modulated oscillations |
This place covers:
Phase or frequency detector generating up-down pulses at separate terminals of the detector.
This place covers:
The up-down pulses being generated by the same phase or frequency detector.
This place covers:
Means for adjusting or tuning the value of the source or sink current.
the phase or frequency detector using a sampling device (H03L 7/087 takes precedence)
This place covers:
Phase or frequency detectors comprising sampling devices such as flip-flops, A/D converters, or the like.
This place covers:
Loop filtering, amplification, or any other manipulation of the signal provided by the phase/frequency detector which results in a control signal for the controlled oscillator of the loop.
This place covers:
Details of the lock detector.
Lock detectors without any detailed features. The lock detectors without detailed features are classified in other subgroups according to the purpose/use of the said lock detector.
This place covers:
Frequency to voltage converters converting the frequency of the reference signal and the frequency of the feedback signal to a voltage, current or digital signal. The voltage, current or digital signal is used by the comparator.
This place covers:
Digital oscillators which are analogly or digitally controlled.
This place does not cover:
Analog oscillators which are digitally or numerically controlled (DCO, NCO) |
This place covers:
Counter or frequency divider being part of the controlled digital oscillator.
This place does not cover:
Counters or frequency dividers which are part of the feedback path or output path outside the loop. |
This place covers:
Digital oscillators comprising an accumulator e.g. Direct Digital Synthesizers (DDS).
This place does not cover:
Direct Digital Synthesizers DDS per se, which are not part of a PLL. |
This place covers:
Means for speeding up the lock-in of the loop in general.
This place covers:
Low pass loop filter having a variable bandwidth for the purpose of assuring synchronisation or broadening the capture range of the PLL.
This place does not cover:
Low pass loop filter having a variable bandwidth for other purposes. |
This place covers:
Arrangements and methods for assuring constant output frequency of the generator when the reference signal fails or is interrupted, or when the control signal of the controlled oscillator of the PLL or the controlled delay of the DLL fails or is interrupted.
This place covers:
Mixer in addition to the frequency divider or counter.
This place does not cover:
Mixer without a frequency divider or counter. |
When the means for coarse tuning the controlled oscillator is not specific for frequency synthesizers, the document would be (additionally) classified in the subgroup H03L/10.
This place covers:
At least two different signals generated by the frequency divider or the counter or derived from frequency divider or counter output are used by the phase/frequency detector.
This place covers:
Also multi-modulus dividers.
Attention is drawn to the following places, which may be of interest for search:
Details of pulse counters or frequency dividers | |
Pulse counters comprising counting chains; Frequency dividers comprising counting chains | |
Pulse counters with step-by-step integration and static storage; Analogous frequency dividers | |
Pulse counters in which pulses are continuously circulated in a closed loop; Analogous frequency dividers | |
Pulse counters comprising multi-stable elements, e.g. for ternary scale, for decimal scale; Analogous frequency dividers |
This place does not cover:
Indirect frequency synthesis using a frequency divider or counter comprising a commutable pre-divider, e.g. a two modulus divider |
Attention is drawn to the following places, which may be of interest for search:
Details of pulse counters or frequency dividers | |
Pulse counters comprising counting chains; Frequency dividers comprising counting chains | |
Pulse counters with step-by-step integration and static storage; Analogous frequency dividers | |
Pulse counters in which pulses are continuously circulated in a closed loop; Analogous frequency dividers | |
Pulse counters comprising multi-stable elements, e.g. for ternary scale, for decimal scale; Analogous frequency dividers |
This place covers:
Also Delta-Sigma modulators used for controlling the counter or frequency divider.
This place covers:
More than loop having each its own controlled oscillator and/or phase shifter.
This place does not cover:
More than loop sharing a controlled oscillator and/or phase shifter with or without use of a switching means. |
This place covers:
e.g. injection-locked oscillators, oscillator arrays, mutually-coupled oscillators.
This place covers:
e.g. atomic clocks.