Abstract: A push button switch including a piezoelectric element (10) which is arranged between a first electrode (16) and a second electrode (18) in such a manner that, when a pressure is exerted on the piezoelectric element, an electric voltage is generated between the first and the second electrode (16, 18). The voltage generated between the first and the second electrode (16, 18) of the piezoelectric element (10) is amplified via a suitable amplifier circuit (20) and supplied, for example, to a controller of an operating device of an electronic domestic appliance.

Abstract: A control device for an electronic domestic appliance has a control panel of an electrically conducting material and an electronic control system with a mains-connected circuit and a circuit that is galvanically separated from the mains. To protect the electronic control system from electrostatic discharges the control panel is grounded by way of an electrical connection between the control panel and the circuit that is galvanically separated from the mains and also an electrical connection between the galvanically separated circuit and the mains-connected circuit. The latter electrical connection between the galvanically separated circuit and the mains-connected circuit has at least one protection impedance.

Abstract: A push button switch including a piezoelectric element (10) which is arranged between a first electrode (16) and a second electrode (18) in such a manner that, when a pressure is exerted on the piezoelectric element, an electric voltage is generated between the first and the second electrode (16, 18). The voltage generated between the first and the second electrode (16, 18) of the piezoelectric element (10) is amplified via a suitable amplifier circuit (20) and supplied, for example, to a controller of an operating device of an electronic domestic appliance.

Abstract: A control device for an electronic domestic appliance has a control panel of an electrically conducting material and an electronic control system with a mains-connected circuit and a circuit that is galvanically separated from the mains. To protect the electronic control system from electrostatic discharges the control panel is grounded by way of an electrical connection between the control panel and the circuit that is galvanically separated from the mains and also an electrical connection between the galvanically separated circuit and the mains-connected circuit. The latter electrical connection between the galvanically separated circuit and the mains-connected circuit has at least one protection impedance.

Abstract: A circuit configuration for a capacitive touch switch contains at least one sensor circuit with a capacitive sensor element which changes its capacitance value when touched, and an evaluation circuit which is supplied with an output signal from the sensor circuit in order to determine whether the capacitive sensor element is actuated or not. The at least one sensor circuit has a capacitance which is connected in parallel with the capacitive sensor element, and a capacitance/frequency converter which is connected to the parallel circuit containing the capacitance and the capacitive sensor element and generates, at its output, a frequency signal whose frequency depends on the total capacitance of the parallel circuit containing the capacitance and the capacitive sensor element. The evaluation circuit may thus use a significant change in the frequency of the output signal from the sensor circuit to deduce, in a simple manner, that the capacitive sensor element has been touched.

Abstract: A circuit configuration for a capacitive touch switch contains at least one sensor circuit with a capacitive sensor element which changes its capacitance value when touched, and an evaluation circuit which is supplied with an output signal from the sensor circuit in order to determine whether the capacitive sensor element is actuated or not. The at least one sensor circuit has a capacitance which is connected in parallel with the capacitive sensor element, and a capacitance/frequency converter which is connected to the parallel circuit containing the capacitance and the capacitive sensor element and generates, at its output, a frequency signal whose frequency depends on the total capacitance of the parallel circuit containing the capacitance and the capacitive sensor element. The evaluation circuit may thus use a significant change in the frequency of the output signal from the sensor circuit to deduce, in a simple manner, that the capacitive sensor element has been touched.