Patent ID: 8264296
Filing Date: 2012-09-11
Classification: H03B

Abstract:
1. A voltage controlled oscillator that changes an oscillatory frequency in accordance with a control voltage, comprising a crystal resonator and a control voltage supply terminal through which a control voltage is applied, wherein a first resistor and a first capacitor are connected in series on a line of the crystal resonator and the control voltage supply terminal, a cathode of a first variable-capacitance diode is connected between the first resistor and the first capacitor, and an anode of the first variable-capacitance diode is grounded, a first parallel-connected circuit is disposed between the first capacitor and the crystal resonator, the first parallel-connected circuit including a second variable-capacitance diode and a second capacitor connected in series, and a first coil, which are connected in parallel, a point between the first capacitor and the first parallel-connected circuit on an input side is grounded via a second resistor, and a point between the first resistor and the first capacitor and a point between a cathode of the second variable-capacitance diode and the second capacitor are connected via a third resistor.