Patent ID: 8446192

Claim:
A PLL circuit comprising a voltage-controlled oscillator which oscillates a frequency in accordance with a control voltage, the PLL circuit further comprising: a reference frequency generation circuit which outputs a constant frequency corresponding to a channel number; phase comparison means for comparing a frequency divided at a frequency division ratio at which the output frequency of the voltage-controlled oscillator is set with the output frequency of the reference frequency generation circuit to output a phase difference; a loop filter which generates the control voltage based on the phase difference; and a control section which comprises a frequency division ratio table where frequency division ratios to improve spurious output characteristics in the output of the voltage-controlled oscillator for each channel number are stored and which, upon input of the channel number from the outside, reads the frequency division ratio corresponding to the input channel number from the frequency division ratio table to set the frequency division ratio in the phase comparison means and to set the channel number and the frequency division ratio in the reference frequency generation circuit, wherein the reference frequency generation circuit calculates the value of a reference frequency based on the channel number and the frequency division ratio to generate the reference frequency corresponding to the calculated value.