A CMOS Readout Circuit for Silicon Resonant Accelerometer with 32-ppb bias stability

Abstract

This paper describes a fully-differential CMOS readout circuit for silicon micro-resonant accelerometer. Tested with a SOI resonator, the readout chip sustains the oscillation at 110 kHz with a phase noise of -36 dBc@1 Hz and a bias stability of 0.0035 Hz or 32 ppb, which can be translated to an amplitude noise of 1 Aring/radicHz down to 0.05 Hz and stability of 0.22 Aring up to 100 seconds. The chip is fabricated in a 0.35-mum CMOS process and draws 5 mA under a 3.3-V single supply.