可编程函数发生器对晶体振荡器的温度补偿

TEMPERATURE COMPENSATING OF CRYSTAL-CoNTRoLLED OSCILLATOR WITH PROGRAMMABLE FUNCTION GENERATOR

为了补偿晶体振荡器的频率受环境温度影响而产生的变化,用可编程函数发生器产生校正信号——校正信号的数值是温度的二次或三次函数(取决于振荡器所选用的石英晶体的切割类型),将它馈送给石英晶体振荡电路中的可调阻抗,以抵消晶体振荡器频率的热变化。

For compensating temperature-dependent frequency variation of crystal oscillator, the programmable function generator provides the corrective signal. The signal of a magnitude varis as a function of frequency and related to the frequency/temperature respone. The respone follows a square law or a third-order polynomial with a linear and a cubic term (according to the cutting type used on the crystal). The correct signal is fed to the crystal-oscillator for the compensation.