| 摘要 |
PURPOSE:To obtain a compact piezoelectric oscillator which can be controlled easily with small power consumption, high reliability and highly stable low frequency, by extracting a difference of frequency between the piezoelectric oscillator of the same cut and performing the compensation of temperature to said frequency difference through digital control. CONSTITUTION:The outputs of a digital control oscillator 10 and a piezoelectric oscillator 20 are supplied to a mixer 30, and a low pass filter 40 and an amplifier 50 are connected to the mixer 30. These component elements are set on the same substrate and put into the same case 60. The 1st digital amount of output is obtained from a temperature digital converter 11 at a certain temperature. Then the output given from a digital control piezoelectric oscillator 13 is varied to obtain the 2nd digital amount of the oscillator 13 when the final output frequency of the signal delivered from the amplifier 50 reaches a desired level. Hereafter the temperature is varied to obtain successively the 1st digital amount and its corresponding 2nd digital amount. These obtained data are stored to a digital/digital converter 12 with correspondence to each other.
|
