OPERATION METHOD AND CIRCUIT ARRANGEMENT FOR A CAPACITIVE MICROMECHANICAL SENSOR WITH ANALOG RESET

摘要

: The invention relates to a method and a switch arrangement for operating a micromechanical capacitive sensor having at least one, and at most two, fixed electrodes (El, E2) and one differential capacitor formed by a movable central electrode (EO) that can be deflected by an external force, wherein the deflection of said electrode (EO) is measured. The invention provides that a fraction of the force acting on the central electrode corresponding to the electrostatic restorative force be compensated. Under closedloop operation of the sensor, the selection signal is influenced by a regulator supplementing a restorecrosstalk signal in such a manner that the created capacitive restorative force acts in a compensatory manner against the deflection of the central electrode. Two embodiments of the invention and a measure supplementing said embodiments for optimizing the control are presented. No. of Pages : 23 No. of Claims : 14