| 摘要 |
PROBLEM TO BE SOLVED: To provide a PLL circuit capable of realizing application of an accurate phase offset by providing an offset current application section into a charge pump circuit. SOLUTION: In the PLL circuit provided with: a voltage-controlled oscillator (40) the frequency of the output clock of which is controlled by an input voltage; a frequency divider (50) for dividing an output signal of the voltage-controlled oscillator; a phase comparator (10) for comparing a phase of an output signal of the frequency divider with a phase of a reference signal; a charge pump circuit (20a) driven by an output signal of the phase comparator; and a loop filter (30) for integrating an output of the charge pump circuit, and controlling the frequency of the voltage-controlled oscillator with a voltage stored in the loop filter, the charge pump circuit is provided with a means for generating an offset current to change the phase of the output clock. COPYRIGHT: (C)2004,JPO
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