中文摘要：

为了实现AC（工频）和DC电场同时检测，该文基于MEMS电场传感器，采用直接数字频率合成器（DDS）激励及正交锁相技术研制出一种高性能微型电场传感器电路。该系统结合低噪声模拟电路和数字控制方式，采用DDS 产生精准的传感器激励信号和双路正交参考信号，保证了激励信号及正交参考信号的频率、幅值稳定性以及双路正交参考信号之间准确的相位差。采用相关解调芯片及高速滤波器构建正交锁相放大电路，结合 Advanced RISC Machines （ARM）微控制器，解决了单片机数字信号处理响应速度慢、资源不足等问题，成功实现AC（工频）及DC电场加载情况下传感器弱信号高精度提取。

英文摘要：

A novel and high-performance micromachined electric-field sensor system circuit which can measure both AC （50 Hz） and DC fields is presented based on Direct Digital Synthesizer （DDS） and Lock-In-Amplifier （LIA）. The system combines low-noise analog circuits and digital control scheme, using DDS to generate the excitation signal and the orthogonal reference signals, ensures the frequency and amplitude stability of the excitation signal and precise phase difference between the orthogonal reference signals. Using demodulator chip and high-speed filter to build quadrature lock-in amplifier circuit, combining with the ARM microcontroller, the system achieves a faster response and saves much more sources than the simple digital processing circuit.