A Mode-Matching $\Sigma\Delta$ Closed-Loop Vibratory Gyroscope Readout Interface With a 0.004$^{\circ}$ /s/$\surd{\hbox{Hz}}$ Noise Floor Over a 50 Hz Band

This vibratory gyroscope readout interface exploits mode matching and boxcar sampling to reduce power dissipation. The interface ensures mode matching over MEMS and IC fabrication tolerances and ambient variations using background calibration, and addresses the bandwidth and gain-stability challenges raised by the high-Q sense element using a force-feedback architecture that is robust against spurious mechanical resonances. The interface is fabricated in 0.35-mum CMOS and achieves a noise floor of 0.004
^deg
s/radicHz over 50 Hz while dissipating 1 mW.