A 104-dB Dynamic Range Transimpedance-Based CMOS ASIC for Tuning Fork Microgyroscopes

A. Sharma, M.F. Zaman, F. Ayazi
2007 IEEE Journal of Solid-State Circuits  
In this paper, the design, implementation and characterization of a continuous time transimpedance-based ASIC for the actuation and sensing of a high-MEMS tuning fork gyroscope (TFG) is presented. A T-network transimpedance amplifier (TIA) is used as the front-end for low-noise, sub-atto-Farad capacitive detection. The T-network TIA provides on-chip transimpedance gains of up to 25 M, has a measured capacitive resolution of 0.02 aF/ Hz at 15 kHz, a wide dynamic range of 104 dB in a bandwidth of
more » ... 10 Hz and consumes 400 W of power. The CMOS interface ASIC uses this TIA as the front-end to sustain electromechanical oscillations in a MEMS TFG with motional impedance greater than 10 M. The TFG interfaced with the ASIC yields a two-chip angular rate sensor with measured rate noise floor of 2.7 /hr/ Hz, bias instability of 1 /hr and rate sensitivity of 2 mV/ /s. The IC is fabricated in a 0.6-m standard CMOS process with an area of 2.25 mm 2 and consumes 15 mW. Index Terms-Capacitive interface circuit, input-referred current noise, microgyroscope, transimpedance.
doi:10.1109/jssc.2007.900282 fatcat:bw7zldowlvawpeyhudwz2bnntu