A circuit for evaluating measurement signals of at least one sensor with a control circuit. A control signal having a first frequency is generated by a control section of the control circuit, and the control signal is applied to the sensor. An electronic evaluation unit is provided for generating an evaluation signal originating from a measurement signal generated by the sensor. The electronic evaluation unit generates an opposing signal having the first frequency and a modifiable phase angle and superposes the opposing signal and the evaluation signal. The signal resulting from the superposition of the opposing signal and the evaluation signal is fed to a synchronous demodulator of the electronic evaluation unit.