Patent ID: 7986194

Claim:
An oscillator, comprising: an amplifier circuit; a first variable capacitance element, a control voltage being connected to a first end of the first variable capacitance element and a reference voltage being connected to a second end of the first variable capacitance element between the second end of the first variable capacitance and an input of the amplifier circuit; a second variable capacitance element, the control voltage being connected to a first end of the second variable capacitance element and the reference voltage being connected to a second end of the second variable capacitance element between the second end of the second variable capacitance and an output of the amplifier circuit; a piezoelectric resonator; a capacitance circuit constituting a closed circuit with the piezoelectric resonator; and a series circuit, the series circuit including the amplifier circuit, the first variable capacitance element, and the second variable capacitance element connected in series and the series circuit and the closed circuit being connected in parallel.