A MEMS piezoresistive inclination sensor with CMOS ASIC front-end interface

Abstract

In this paper a system for inclination measurement is presented. It consists of a MEMS piezoresistive accelerometer manufactured in silicon bulk micromachining and an application specific integrated circuit (ASIC) specifically designed for resistive-bridge sensors. The interface circuit excites the sensor with a constant current and converts both the unbalance and the overall resistance of the sensor bridge respectively into the frequency and the duty cycle of a rectangular-wave output signal. DC current excitation of the sensor makes the configuration unaffected by wire resistance and parasitic capacitances, therefore the sensor can be placed remotely from the electronics without suffering accuracy degradation. © 2010 Springer Science+Business Media B.V.