Patent ID: 7276979

Claim:
An oscillation device, comprising: a differential type voltage control oscillator that includes a differential variable capacitance circuit of which the differential capacitance varies in accordance with a differential control voltage; and a control circuit for supplying said differential control voltage to said differential variable capacitance circuit, wherein said differential variable capacitance circuit is formed of at least one pair of varactor diodes which are connected to each other in an anti-parallel manner, and of a group of capacitors for separating direct currents flowing through said varactor diodes, and said differential control voltage of said control circuit is respectively applied to the cathodes and the anodes of said varactor diodes, and wherein said control circuit comprises: a reference signal generator for generating a reference signal; a phase comparator which compares the phase between said reference signal and an external signal, and which outputs the phase comparison result of a phase delay or a phase advance of said external signal relative to said reference signal from a frequency up control output terminal or from a frequency down control output terminal, as a frequency up control output or as a frequency down control output; at least one first charge pump circuit which outputs a voltage higher than a predetermined first voltage in response to said frequency up control output, and which outputs a voltage lower than said first voltage in response to said frequency down control output; and at least one second charge pump circuit which outputs a voltage higher than a predetermined second voltage in response to said frequency up control output, and which outputs a voltage lower than said second voltage in response to said frequency down control output, wherein an output signal of said differential type voltage control oscillator or a frequency dividing signal thereof is inputted into said phase comparator as said external signal, and an output voltage of said first charge pump circuit is respectively applied to the cathodes of said varactor diodes as said differential control voltage, and an output voltage of said second charge pump circuit is respectively applied to the anodes of said varactor diodes as said differential control voltage.