MULTI-SENSORY COMBINED INTEGRATED LOW POWER TUNABLE-GAIN INTERFACE CIRCUIT

Abstract

This paper presents MEMS multi-sensors with low power tunable-gain interface circuit that can be monolithically integrated in the ASIC compatible standard CMOS process. A high gain ultra-low power sustaining TIA amplifier circuit with PLL compactly has been integrated with the resonator-based core sensing structure. The proposed low-power readout circuit adopts Correlated Double Sampling (CDS) to suppress low frequency noise and compensate DC offset. The gyroscope sensitivity is designed to be 1.8 aF/degrees/sec within +/- 100 degrees/sec. The tunable sensitivity can be adjusted from 28 mV/fF to 224 mV/fF by fully-differential programmable-gain amplifier (PGA). The interface circuit has 61.12dB SNR under 500 KHz sampling rate.