Patent · US Expired

PLL clock generator, optical disc drive and method for controlling PLL clock generator

US7339861B2 · kind B2 · utility

9Cited by
3References
10Claims
0Family size

Assignee

Inventors

Key dates

Filing dateApr 14, 2004
Grant dateMar 4, 2008
Priority date
Expiry dateSep 19, 2025

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH03L7/0891
  • WIPO fieldBasic communication processes
  • WIPO sectorElectrical engineering

Abstract

A PLL clock generator generates an output signal with a frequency N times (where N≧1) as high as that of an input signal. The clock generator includes: a frequency divider for dividing the frequency of a clock signal by N so as to output a frequency-divided clock signal; a phase comparator for detecting a phase difference between the input signal and the output signal of the frequency divider so as to output a phase difference signal including information representing the phase difference; a LPF for smoothing the phase difference signal; a VCO for generating the clock signal, of which the frequency is determined by the output of the LPF, and outputting the clock signal to the frequency divider; and a phase shifter for shifting the phase of the output signal of the frequency divider in accordance with the phase difference signal.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.