Patent ID: 7248127
Filing Date: 2007-07-24
Classification: H03B,H03L

Abstract:
1. A crystal oscillator comprising: a resonance circuit having a crystal unit and a split capacitor connected to said crystal unit; a transistor for oscillation having a base connected to a node of said crystal unit and said split capacitor; an output line for connecting an emitter of said transistor to a mutual node of said split capacitor; a crystal resonator inserted in said output line; and a temperature compensation mechanism for compensating frequency-temperature characteristics of both said crystal unit and said crystal resonator, wherein said temperature compensation mechanism comprises a first voltage-variable capacitance element connected to said crystal unit, a second voltage-variable capacitance element connected to said crystal resonator, and a single compensating voltage generation circuit for generating a compensating voltage according to ambient temperature, wherein said compensation voltage is applied to said first and second voltage-variable capacitance elements.