Design of a micromachined CMOS compass

This paper presents the design of a low-cost monolithic CMOS microcompass. The system is based on a cantilever actuated by the Lorenz force. Conditioning circuitry has been designed carefully to reject noise, to eliminate parasitic phenomena such as thermal effects, and to be robust to process scatterings without the need of an external trimming. Mixed-mode simulations have been enabled using a behavioral description of the sensor, and validations of the complete system have been performed. The expected performance has a resolution inferior to 1° for a total surface of 10.6mm² and a power consumption of 56mW (without the digital processing bloc).