A 2.2 mA 4.3 mm² ASIC for a 1000∘/s 2-Axis Capacitive Micro-Gyroscope

The interface for a capacitive 2-axis micro-gyroscope is implemented in a 0.35-μm HVCMOS technology with a total area of 4.3 mm2. The ASIC comprises the complete analog interface electronics for the gyroscope, while the focus of the design is in maintaining low supply current and in reducing the chip area. The paper reports the design of reference circuits, high-voltage generation, drive-loop and the capacitive open-loop readout circuits. The prototype sensor that is measured is assembled by directly wire-bonding the stacked dies comprising the interface electronics and the sensor element. The noise floors of the two sensors are 0.028°/s/√{Hz} for z-axis and 0.032°/s/√{Hz} for y-axis. The supply current of the chip is 2.2 mA from a 3 V-supply.