| 摘要 |
The invention in one embodiment provides a circuit arrangement for a sensor element of a contact switch, in which a high frequency control signal (13) is applied to the sensor element (15). The circuit arrangement (11) has a signal source (12) for the control signal (13), a transistor (T), to whose base (B) is applied across a pass filter (R1, C1) and a voltage divider (C1, 15) the control signal (13), a resistor (R2) applied to ground (18) ensuring a certain base current, the transistor collector (C), to which the output signal (17) is applied, is connected to ground across a capacitor (C2), whilst between the transistor base (B) and ground is located a capacitive sensor element (15). A preferred application field of the invention is a touch contact switch of a glass ceramic hotplate of an electric cooker.
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