MEMS重力計向け、高増幅・低ドリフトDC読み出し用電子回路

Microelectromechanical systems (MEMSs) based gravimeters are a convenient solution for field applications. For some of these devices, their readout relies on measuring the mass displacement using the signal change in a quadrant detector. Reaching a precision at the μGal level depends on having a very high signal-to-noise ratio. In this paper, we present an electronic circuit that achieves an enhanced amplification by continuously removing the offset in the signal. We obtain the extra amplification without reducing the full dynamic range of the sensor and without adding any additional drifts coming from thermal variations.