A Low Flicker Noise Automatic Amplitude Control ASIC for a Split-Mode MEMS Gyroscope

This paper presents a fully differential low flicker noise automatic-amplitude-control (AAC) ASIC for a split-mode MEMS gyroscope. The impact of flicker noise in AAC on the gyroscope's bias instability is firstly analyzed. Chopper stabilized amplitude detector and error amplifier are employed to remove their flicker noise. A second-order loop filter attenuates the flicker noise from variable gain amplifier (VGA). The ASIC is fabricated in TSMC 0.35μm CMOS process and consumes 1mW power with a 3.3V supply voltage. Experimental results indicate the flicker noise component in the gyroscope's drive amplitude is greatly reduced.