Micromachined Electric-field Sensor System Based on Direct Digital Synthesizer and Lock-in-amplifier to Measure AC and DC Fields
Ren Dong-yu①② Peng Chun-rong① Xia Shan-hong①
①(State Key Laboratory of Transducer Technology, Institute of Electronics, Chinese Academy of Sciences, Beijing 100190, China) ②(University of Chinese Academy of Sciences, Beijing 100039, China)
Abstract: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.
任东宇, 彭春荣, 夏善红. 基于直接数字频率合成器及正交锁相技术的交直流微型电场传感器电路[J]. 电子与信息学报, 2013, 35(12): 3030-3036.
Ren Dong-Yu, Peng Chun-Rong, Xia Shan-Hong. Micromachined Electric-field Sensor System Based on Direct Digital Synthesizer and Lock-in-amplifier to Measure AC and DC Fields. , 2013, 35(12): 3030-3036.