LINEAR MEMS DIFFERENTIAL CAPACITANCE SENSING SCHEME
Original Publication Date: 2000-May-01
Included in the Prior Art Database: 2002-Sep-25
MEMS (micro electro-mechanical system) devices have been used previously to measure acceleration parallel to Cartesian coordinate axes (x, y, z). Similarly, rotational rates have been measured with respect to x, y, and z axes. MEMS acceleration sensors are typically comprised of differential capacitance parallel plates in which the dielectric gap is modulated as a function of applied acceleration. The sensor differential capacitance is signal conditioned using a CMOS control circuit. The CMOS control circuit translates the acceleration mechanical input signal from the sensor into an electrical output such as an output voltage (mV/g) or frequency (Hzlg).