METHOD FOR MEASURING A CAPACITANCE VALUE

摘要

A method for measuring a capacitance value of a capacitive sensor uses an integration process. For the integration process, the sensor is connected to an integration capacitor having a known capacitance value greater than the capacitance value of the sensor and a voltage UCI of the integration capacitor is measured by an A/D converter after a number IZ of executed integration cycles of the integration process. The method includes carrying out the integration process until the number IZ of executed integration cycles has reached the number N of integration cycles to be executed, adding a voltage value UCI (N) of the integration capacitor, which is determined by the A/D converter, to the total voltage value Utotal, increasing the number N, and repeating until the number N exceeds a predetermined value. The final total voltage value Utotal is indicative of the capacitance value of the capacitive sensor.