| 摘要 |
PROBLEM TO BE SOLVED: To provide a phase-locked loop circuit having a wide range of synchronization and to provide a semiconductor integrated circuit device which is provided with the circuit. SOLUTION: The phase-locked loop circuit having a wide range of synchronization is provided with a phase frequency detecting part for detecting the difference of phases between an external input signal and an output signal of the phase-locked loop circuit, a charge pump which increases and decreases a voltage which is outputted in response to an output signal of the phase frequency detecting part, a loop filter for removing a high frequency component contained in an output voltage of the charge pump, a voltage control oscillator which outputs a signal having a prescribed frequency as an output signal of the phase-locked loop circuit in response to an output voltage of the loop filter, and a VCO range shift part which reduces the sensitivity of the output signal of the phase-locked loop circuit to the output voltage of the loop filter by increasing and decreasing an internal current of the voltage control oscillator in response to the output voltage of the loop filter. As a result, jitter generated in the output signal of the phase-locked loop circuit is reduced even if a noise voltage flows into the output voltage of the loop filter. COPYRIGHT: (C)2004,JPO
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