In order to eliminate the strong coupling effect between the thermal driving and the piezoresistive sensing and to satisfy the requirement of component miniaturization,a simple and easy-operating differential measurement circuit was designed and produced for I2 shaped MEMS resonator. The measurement circuit consisted of a signal generator,a combiner and amplifier, a lock-in amplifier and a resistor. An experiment was carried out. Evidence showed that the coupling effect was effectively eliminated,and the output signal quality was obviously improved by using the differential measurement circuit. A clear resonance peak and phase rotation was also observed. Comparing with other methods of eliminating the coupling effect ( e. g. frequency mixing technique or inactive resonator technique) , the differential measurement requires neither complicated electronic circuit design nor demanding micro-fabrication effort,which will favor the device downscaling process for future applications.%为克服I2形MEMS谐振器输入端(热执行)与输出端(压阻敏感)直接耦合所造成的输出信号品质较差的缺点，设计并制作了一种电阻差分检测电路。该电路通过外接电阻的方法，产生与输出信号中耦合成分幅值相同、相位相反的差分信号。将差分信号与谐振器输出信号相组合，从而实现解耦的目的。实验结果表明，电阻差分检测可有效消除了输出信号中的耦合成分，使频谱响应曲线得到更直观的体现。与其他消除耦合信号的技术方案相比(混频检测电路、惰性谐振器等)，电阻差分检测法电路设计简单，无需改动器件的加工工艺，有利于满足未来器件小型化要求。
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