为提高石英晶体的测试效率，搭建了双独立通道的鉴相系统。该系统采用同一DDS信号源同时激励两个π网络电路，设计了两个独立的鉴相电路，可实现两个通道同时鉴相。该系统采用差频鉴相的方法，使用AD8302作为鉴相器件，在提高鉴相的效率的同时确保了π网络零相位法的检测精度。为验证其可行性，将该系统应用到石英晶体电参数测量系统中。该双独立通道鉴相系统的频率测试范围为1~200 MHz，实验结果表明，鉴相精度达到±1°，满足石英晶体的测试需要。%In order to improve the measuring efficiency of quartz crystal,a two⁃channel phase discriminator system applied to quartz crystal test is designed. One DDS signal generator are used in the system to inspire two π⁃network circuits. The two in⁃dependent phase discriminator circuits are designed to discriminate the phase of two channels simultaneously. The difference fre⁃quency phase discriminating method is adopted in the system. The AD8302 is taken as a phase discriminator,which can im⁃prove the testing efficiency and ensure the testing precision simultaneously. In order to verify the viability of two⁃channel phase discriminator,it was used in a electrical parameter measuring system for quartz crystal test. The testing range of the two⁃channel phase discriminator system is 1~200 MHz. The experiment result shows that its phase discrimination accuracy is ±1°,which can meet the testing needs of quartz crystal.
展开▼
