Design of a ∑-△ converter based automotive sensor

摘要

The design of a second order Σ - Δ converter based microaccelerometer is presented in this paper. This converter has a large dynamic range, i.e., can measure acceleration from 0.5 g to 500 g, and provides directly digital output. The force-rebalance circuitry constraints the sensor mass to move within 10% of the distance between the polysilicon layers. The system is inherently linear and has a simple electronic interface.