SHI Zhan，DONG Lin-xi
（Key Lab of RF Circuit and System Ministry of Education，Hangzhou Dianzi University，Hangzhou 310018，China）
Abstract：Aiming at collecting faint seismic data，MEMS sensor technology was applied to design a seismic data acquisition system. Thesystem design based on MEMS accelerometer and 24-bit ADC convertor was presented. Precision instrumentation amplifier was used todeal with the differential signal from MEMS sensor. In this mix-signal system，isolation scheme was adopted when design PCB to isolatethe digital and analog circuit to suppress interference from each other. The magnetic coupling isolator was used to isolate thecommunication interface between ADC convertor and micro controller. According to the command transmitted from upper system byLabVIEW，real-time seismic data could be displayed in the form of waveform and stored in SD card. The software process and hardwaredesign of the system was analyzed. The signal generator was used to measure the accuracy and frequency response of the system，theprocess of data acquisition was tested under a simulated environment. The experimental results indicate that system accuracy reaches themagnitude of 10 μV，the quality of acceleration signal reconstruction is good and the designed system meets requirements of seismic dataacquisition.
Key words：micro-electro-mechanical systems（MEMS）；accelerometer；seismic data acquisition；24-bit A/D；mixed-signal PCB；real-time data storage；LabVIEW