Evaluation method for capacitive sensor e.g. for automobile tyre pressure sensor, using comparison of sensor actual value with comparison capacitance provided by switched partial capacitances

摘要

The evaluation method compares an actual value provided by the capacitive sensor (Csensor) with the value provided by a comparison capacitance provided by a number of partial capacitances (C0-C9) connected in together via respective switches (S0-S9), the switch positions (p1,p2) providing digital information directly proportional to the capacitive sensor actual value. An Independent claim for a circuit for evaluating an actual value provided by a capacitive sensor is also included.