Patent ID: 6424231
Filing Date: 2002-07-23
Classification: H03B

Abstract:
A voltage controlled oscillation circuit connected to a first capacitor, the voltage controlled oscillation circuit:an amplifier circuit; a resonance circuit connected to said amplifier circuit; a varactor diode connected to said resonance circuit, an anode of said varactor diode being grounded; a choke element having one end thereof connected to a cathode of said varactor diode, said choke element having an inductance element and a second capacitor connected to said inductance element in parallel wherein a parallel resonance occurs in a vicinity of an oscillation frequency; a third capacitor connected between an other end of said choke element and a ground; and an impedance element with a first end connected to the other end of said choke element, a second end of said impedance element being connected to a control voltage terminal; wherein one end of said first capacitor is connected to the second end of said impedance element and to said control voltage terminal, and an other end of said first capacitor is connected to ground.