Method for operating a capacitive switch and capacitive switch circuit

摘要

A measurement signal provided by an oscillator (1) is subjected to a frequency spread in a first correlator (8) by modulation with a noise source (7), fed to one input of a second correlator (9) and to the transmission electrode of a capacitor sensor (4). The signal received by the sensor measurement electrode is fed to a second input of the second correlator and its output signal processed by an evaluator circuit (3).