A 3-axis accelerometer and strain sensor system for building integrity monitoring

Abstract

An Ultra-Low-Power readout architecture for capacitive MEMS-based accelerometers and strain sensors is presented. The system can read both accelerometers and strain sensors in a half-bridge configuration. The gain is controlled by integrating pulses from the excitation voltage allowing accurate control of the Signal-to-Noise ratio. A Figure-of-Merit of 4.41×10 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">-20</sup> F√(W/Hz) was achieved for a sensor range of ±2.0g and ±20,000με over a 100Hz bandwidth. Residual motion artifacts are also cancelled by the system.