Patent ID: 8384450

Claim:
A frequency synthesizer device comprising: a voltage-controlled oscillation unit that oscillates at an oscillation frequency in accordance with an inputted control voltage; a frequency division unit that frequency-divides an output signal from the voltage-controlled oscillation unit, a frequency division ratio thereof being variable on the basis of an inputted frequency setting signal; a frequency phase comparison unit that outputs a phase difference, between a frequency-divided signal that has been frequency-divided by the frequency division unit and a reference clock, to the voltage-controlled oscillation unit as the control voltage; an adjustment voltage output unit that outputs transmission data to the voltage-controlled oscillation unit and that outputs an adjustment voltage to the voltage-controlled oscillation unit when the oscillation frequency is to be displaced by an amount corresponding to a target frequency displacement in accordance with the transmission data; a switch that, at a time of correction of the adjustment voltage, switches from connecting between the voltage-controlled oscillation unit and the frequency phase comparison unit to connecting between the voltage-controlled oscillation unit and a reference voltage power source that supplies a pre-specified reference voltage; and a specification unit that, at the time of correction of the adjustment voltage, specifies adjustment data that corresponds to the adjustment voltage corresponding to the target frequency displacement, on the basis of a count value for which a frequency of the frequency-divided signal is counted in a state in which arbitrary transmission data is outputted to the adjustment voltage output unit and causes the voltage-controlled oscillation unit to oscillate, wherein the frequency division unit includes a first frequency division unit that frequency-divides the output signal from the voltage-controlled oscillation unit with a pre-specified fixed frequency division ratio, and a second frequency division unit that frequency-divides the frequency-divided signal that has been frequency-divided by the first frequency division unit with a frequency division ratio based on the frequency setting signal and outputs an output signal to the frequency phase comparison unit, and the specification unit counts the frequency of either the frequency-divided signal from the first frequency division unit or the frequency-divided signal from the second frequency division unit.