| 摘要 |
PROBLEM TO BE SOLVED: To provide a phase-locked loop(PLL) circuit, which is stably operated even when switching a frequency range, concerning the PLL circuit having a variable frequency range voltage controlled oscillator(VCO). SOLUTION: This PLL circuit is provided with a variable frequency range VCO 104 for switching the oscillation frequency range corresponding to a select signal. In this case, the circuit is further provided with a means 116 for setting the control voltage of the VCO 104 after switching so that the oscillation frequency of the VCO 104 after switching is equal to the oscillation frequency of the VCO 104 before switching when the select signal is switched. |
