| 摘要 |
PROBLEM TO BE SOLVED: To provide a temperature compensation method of a piezoelectric oscillator that can oscillate with a stable oscillation frequency, by reducing the influence of the hysteresis characteristics of the oscillation frequency of a piezoelectric vibrator, and to provide a piezoelectric oscillator. SOLUTION: The piezoelectric oscillator 10 includes the piezoelectric vibrator 12, an oscillation circuit 14 for outputting an oscillation signal 58; a temperature sensor 16 for outputting detection voltage 66, corresponding to the ambient temperature of the piezoelectric vibrator 12; and a storage circuit 20 for storing a first frequency-temperature information 74 having a temperature characteristic, when the temperature is increased and a second frequency-temperature information 76 having temperature characteristics, when temperature drops and outputting them to a temperature compensation circuit 40. The temperature compensation circuit 40 includes a determination circuit 49 for outputting a determination signal for determining the rise and lowering in the temperature of the piezoelectric vibrator 12 from a change in the detection voltage 66; a CPU 44 for selecting either the first frequency-temperature information 74 or the second frequency-temperature information 76, on the basis of the determination signal and using the detection voltage 66 and either the first or the second frequency-temperature information 74 or 76 selected to calculate a temperature compensation amount 80; and a frequency correction circuit 42 for performing temperature compensation of the oscillation signal 58, on the basis of the temperature compensation amount 80. COPYRIGHT: (C)2011,JPO&INPIT
|
