Circuit for evaluating capacitive signal of acceleration sensor

摘要

The evaluation circuit (20) has a first electrode on a vibrating mass, which is deflectable in an electric field between two fixed electrodes depending on the acceleration force. The two fixed electrodes are connected with the outputs of the two drivers (4, 5). The evaluation circuit is designed to detect the voltage at the common centre tapping (c) of the two sensor capacitors (2, 3), and to determine a voltage alteration (DELTA U) after the recharging of these capacitors. The evaluation circuit has a first switch (S1) to connect the centre tapping (c) with the specified voltage (Ub).