A Reconfigurable High-Bandwidth CMOS-MEMS Capacitive Accelerometer Array with High-g Measurement Capability and Low Bias Instability

Xiaoliang Li, Vincent P. J. Chung, Metin G. Guney, Tamal Mukherjee, Gary K. Fedder, Jeyanandh Paramesh

Abstract: This paper presents a high-bandwidth capacitive accelerometer array that is fully integrated with reconfigurable readout circuits and on-chip distributed temperature sensors for environmental monitoring. A parallel array of 338 transducer cells, each with low proof mass, enables measurement of high shock events with low noise. Reconfigurable readout circuitry with continuous-time low-g and switched-capacitor high-g modes enables wide dynamic range acceleration detection and lowers the power 27.5X in high-g mode. A coarse-fine grain offset cancellation technique is proposed to suppress the transducer offset with 168X better tuning resolution than conventional techniques. Implemented in a standard 180 nm CMOS technology and post-processed, the accelerometer achieves 118 kHz bandwidth, high-g (> 10 kg) measurement capability, with low bias instability (22 mg) and zeptofarad offset suppression.