Patent ID: 8242856

Claim:
A piezoelectric oscillator, comprising: a main oscillator unit for outputting a set frequency signal, the main oscillator unit comprising a piezoelectric resonator formed by providing a main electrode for forming a main vibration area on a piezoelectric substrate, and a main oscillator circuit connected to the main electrode; an auxiliary oscillator unit used as a temperature sensor, the auxiliary oscillator unit comprising a piezoelectric resonator formed by providing an auxiliary electrode for forming an auxiliary vibration area on the piezoelectric substrate used for the main oscillator unit separately from the main electrode, the piezoelectric resonator sharing the piezoelectric substrate with the piezoelectric resonator of the main oscillator unit, and an auxiliary oscillator circuit connected to the auxiliary electrode; a temperature estimating unit detecting a frequency of an oscillation output of the auxiliary oscillator unit and estimating a temperature based on the frequency and a temperature characteristic of a frequency of the auxiliary oscillator unit; and a control voltage supply unit obtaining a control voltage for obtaining the set frequency signal based on the temperature estimated by the temperature estimating unit and a temperature characteristic of a frequency of the main oscillator unit and supplying the control voltage to the main oscillator circuit; and wherein the auxiliary oscillator unit comprises a first auxiliary electrode forming a first auxiliary vibration area, a second auxiliary electrode forming a second auxiliary vibration area, a first auxiliary oscillator circuit and a second auxiliary oscillator circuit connected to the first auxiliary electrode and the second auxiliary electrode, respectively, and a unit for obtaining a difference or a sum of respective oscillation frequencies of the first auxiliary oscillator circuit and the second auxiliary oscillator circuit so as to obtain an oscillation output of the auxiliary oscillator unit.