A medical treatment device comprises a sensor to detect operating states of the medical treatment device, wherein the sensor comprises a first electrode, a second electrode and impedance means. The first electrode is arranged between a current path input and a current path output, wherein an electric input signal for powering the medical treatment device is applicable to the current path input, and the current path output is configured to couple to a load of the medical treatment device. The second electrode is separated from the first electrode by a first dielectric material, the second electrode comprising a first signal terminal for obtaining a first sensor signal. The impedance means are separated from the first electrode by a second dielectric material and comprise a second signal terminal for obtaining a second sensor signal. The first electrode comprises a cross section perpendicular to the direction of propagation of the electric input signal such that the first electrode and the second electrode are coupled to provide a capacitance as first sensor signal, and wherein the impedance means are formed as a structured electrode such that the first electrode and the impedance means are coupled to provide an impedance as second sensor signal.