Patent
Horizontal oscillation circuit capable of changing frequency
TLDR
In this paper, a frequency detection circuit detects the frequency of a horizontal sync signal, and generates a mode switching signal corresponding to the detected frequency, and the oscillation modes of the voltage-controlled oscillator are switched in accordance with the frequency detection signal output from the frequency detector circuit.Abstract:
A frequency detection circuit detects the frequency of a horizontal sync signal, and generates a mode switching signal corresponding to the detected frequency. A voltage-controlled oscillator constituting a PLL circuit has a plurality of oscillation modes obtained by dividing a frequency equal to an integer multiple of the frequency of the horizontal sync signal into a plurality of frequency ranges, and oscillates signals in the respective frequency ranges in accordance with control voltages output from a filter. The oscillation modes of the voltage-controlled oscillator are switched in accordance with the mode switching signal output from the frequency detection circuit. In the voltage-controlled oscillator, since the frequency range in each oscillation mode is narrow, the oscillation gain can be suppressed low, and a deterioration in jitter characteristics can be prevented.read more
Citations
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Patent
Power converter circuitry and method
Kent Kernahan,John Carl Thomas +1 more
TL;DR: In this article, a control system and method for simultaneously regulating the operation of a plurality of different types of switching power converters is presented, where the system utilizes in regulating the sampled data and nonlinear feedback control loops.
Patent
Switching power converter employing pulse frequency modulation control
Milton D. Ribeiro,Kent Kernahan +1 more
TL;DR: In this article, a method for controlling a switching power converter provides an efficient algorithm for controlling the output voltage across loads that are relatively light with small transients, which is useful with synchronous or non-synchronous power converters of buck, boost, buck/boost or other topologies.
Patent
Operating an Integrated Circuit at a Minimum Supply Voltage
TL;DR: In this article, an integrated circuit comprises at least one measurement unit configured to generate an output indicative of a supply voltage at which the integrated circuit is operable for a given operating frequency and a control unit coupled to receive the output.
Patent
Switching power converter
Kent Kernahan,John Carl Thomas +1 more
TL;DR: In this article, a switching power converter including a ring oscillator constructed using a plurality of series connected inverters is utilized to generate a plurality waveforms, in cooperation with an exclusive OR gate, which can vary from 0 to nearly 100% duty cycle, depending upon which waveform is selected.
Patent
Dynamic voltage and frequency management
TL;DR: In this paper, a self-calibration unit is configured to iterate a test on a logic circuit in the integrated circuit at respectively lower supply voltage magnitudes until the test fails.
References
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Patent
Phase locked loop having plural selectable voltage controlled oscillators
TL;DR: In this paper, a phase detector, a filter, three VCO's (VCO1, VCO2, and VCO3), a multiplexer, and a frequency divider are presented.
Patent
Phase lock loop with selectable frequency switching time
Craig M. Davis,David A. Byrd +1 more
TL;DR: In this paper, a phase lock loop (PLL) circuit for controlling an oscillator includes a phase comparator, a loop filter, a reference converter and a feedback converter whose performance characteristics are dynamically controlled so as to provide a phase-locked output signal with both high frequency stepping resolution and low phase locking time.
Patent
Synchronous digital detection of position error signal
TL;DR: In this paper, the authors present a digital representation of position error signals (PES) for direct application to a digital signal processor which controls overall servo positioning operations. But their work is limited to the detection of PES by employing a digital integrator which comprises a register and adder.
Patent
CMOS circuit providing 90 degree phase delay
Jaime E. Kardontchik,Sam H. Moy +1 more
TL;DR: In this article, a phase-locked loop was proposed to provide a precise 90° phase shift at the incoming NRZ data rate by using a series of differential inverters and controlling their delays in accordance with the corresponding delays of a ring oscillator that is part of a phaselocked loop.
Patent
Digital voltage controlled oscillator having a ring oscillator with selectable output taps
Takaaki Yamada,Hiroshi Yamagata +1 more
TL;DR: In this article, a digital VCO consisting of a ring oscillator formed of a plurality of inverters connected in series, each inverter being capable of controlling its delay amount, a frequency controlling circuit for controlling the oscillation frequency of the ring oscillators to coincide with a reference frequency, a selector switch for selecting specified output taps from output taps, each thereof being provided for each of the plurality of in-series inverters, to take out the outputs therefrom, and switching control means for controlling outputs from which the outputs are taken out to be cyclically switched through the