石英晶体谐振器负载谐振频率测量技术研究

The research of the measuring technique of the quartz crystal load resonant frequency

石英晶体经常工作于负载谐振状态,由于负载电容的存在,负载谐振频率测量精度的提高存在固有的困难。对π网络零相位法测量石英晶体负载谐振频率的3种测量方法进行了分析,在此基础上,采用内置固定负载电容和电容计设计了π网络零相位型石英晶体电参数测试系统。实验结果表明,负载谐振频率重复测量精度达到了±2×10-6,但需进一步改进以减小系统误差。

Quartz crystal is often in resonance with a load capacitor.Due to the existence of the load capacitor, it is difficult to improve the measuring accuracy of the load resonant frequency.Three methods of measuring quartz crystal load resonant frequency by zero phase technique in a π -network are analyzed. An inner load capacitor and the real time measurement of capacitance are applied to the measurement system. The result of the measurement of some quartz crystals shows that the repeatable measuring accuracy of the load resonant frequency can attain ±2×10^(-6).However,some improvements should be further made to reduce the system error.