Method and apparatus for alleviating charge leakage of vco for phase lock loop
AssigneeRealtek Semiconductor Corp.
InventorsChia-Liang LIN, Chao-Cheng LEE
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Abstract
Methods and apparatuses for alleviating charge leakage of VCO for phase lock loop are disclosed. The method comprises: receiving an input signal; generating an error signal representing a timing difference between the input signal and an output signal; filtering the error signal into a control signal; buffering the control signal into a buffered control signal; and generating the output signal in accordance with the buffered control signal. Buffering the control signal comprising using a high input resistance and low output resistance buffer circuit.
Claims19
An apparatus comprising:
- a phase detector for outputting an error signal in accordance with a timing difference between an input signal and an output signal;
- a loop filter for filtering the error signal into a first voltage signal;
- a voltage buffer for buffering the first voltage signal into a second voltage signal;
- and
- a voltage controlled oscillator (VCO) for outputting the output signal under control of the second voltage signal.
The apparatus of claim 8, wherein the loop filter comprises a capacitor for holding the first voltage signal.
A method comprising:
- receiving an input signal;
- generating an error signal representing a timing difference between the input signal and an output signal;
- filtering the error signal into a control signal;
- using a buffer circuit to buffer the control signal into a buffered control signal;
- and
- generating the output signal in accordance with the buffered control signal.
A method comprising:
- receiving an input signal;
- generating an error signal representing a timing difference between the input signal and an output signal;
- filtering the error signal into a first control signal;
- tracking the first control signal to generate a second control signal;
- and
- generating the output signal in accordance with the second control signal.
Dependencies are inferred from the claim text.