Title :
A Mode-Matching ΔΣ Closed-Loop Vibratory-Gyroscope Readout Interface with a 0.004°/s/√Hz Noise Floor over a 50Hz Band
Author :
Ezekwe, Chinwuba D. ; Boser, Bernhard E.
Author_Institution :
California Univ., Berkeley, CA
Abstract :
A mode-matching DeltaSigma closed-loop vibratory-gyroscope readout interface fabricated in a 0.35 mum CMOS process is presented. This paper describes the architecture and circuits used to exploit mode matching effectively to attain order-of-magnitude noise and power dissipation reductions over state-of-the-art implementations without sacrificing other aspects of system performance. As micromachined vibratory gyroscopes push to lower noise floors, mode matching is necessary to moderate interface power dissipation. Our design overcomes these limitations by using force feedback to achieve a stable scale factor, a well defined phase relationship, and a bandwidth well in excess of 50Hz, commensurate with the requirements of automotive and consumer applications.
Keywords :
CMOS integrated circuits; delta-sigma modulation; force feedback; gyroscopes; micromachining; microsensors; mode matching; readout electronics; CMOS process; DeltaSigma modulator; automotive applications; closed-loop vibratory-gyroscope readout interface; consumer applications; force feedback; frequency 50 Hz; micromachined vibratory gyroscopes; mode matching; order-of-magnitude noise; power dissipation reduction; state-of-the-art implementation; Band pass filters; Electrodes; Feedback loop; Force feedback; Frequency estimation; Power dissipation; Resonance; Resonant frequency; Signal to noise ratio; Voltage;
Conference_Titel :
Solid-State Circuits Conference, 2008. ISSCC 2008. Digest of Technical Papers. IEEE International
Conference_Location :
San Francisco, CA
Print_ISBN :
978-1-4244-2010-0
Electronic_ISBN :
978-1-4244-2011-7
DOI :
10.1109/ISSCC.2008.4523316