A 14 - bit micro-watt power scalable automotive MEMS pressure sensor interface

A technique to improve power scaling efficiency of MEMS interfaces over previous approaches is presented. Power scaling with respect to amplitude is achieved by cascading gain stages through an input gain-select mux, and power scaling with respect to input bandwidth of the sensor is achieved through periodic power-down of the interface. A prototype of the interface was fabricated in 1.8V , 0.18 mum CMOS process. Its power consumption scales between 4 muW -5.33 mW, while maintaining an SFDR of approx. 80 dB, a THD of 78 dB, and an input referred noise of 170.0nV/radicHz.