Proximity switch and method for operating a proximity switch

A method for operating a proximity switch comprising an oscillator including at least one oscillator amplifier, the method comprising:

• generating, by the oscillator, an alternating magnetic field which changes its oscillation state because of a target entering a detection range for the proximity switch;
• detecting, by a temperature sensor, a temperature of an element of the proximity switch or an ambient temperature;
• sending data associated with measured values from the temperature sensor to a microprocessor or to a storage medium coupled to the microprocessor, wherein compensation data is stored on the storage medium;
• generating, by the microprocessor, control data, wherein the generating is based on the temperature detected by the temperature sensor and the compensation data stored on the storage medium;
• and
• sending, by the microprocessor, the control data to at least one temperature compensation circuit within an amplifier stage of the at least one oscillator amplifier, wherein the temperature compensation circuit comprises at least one of a digital potentiometer controlled using the control data or an operational amplifier configured as a voltage follower.

A proximity switch having a defined detection range, the proximity switch comprising:

• an oscillator configured to generate an alternating magnetic field and change its oscillation state as a result of a target entering the detection range, wherein the oscillator comprises at least one oscillator amplifier;
• at least one temperature sensor configured to detect a temperature of an element of the proximity switch or an ambient temperature, wherein
• the oscillator amplifier is configured to be controllable in an open-loop and closed-loop manner and has at least one amplifier stage, and
• the oscillator is controllable based on the temperature detected by the temperature sensor;
• at least one microprocessor configured to control a gain of the oscillator amplifier;
• and
• at least one storage medium coupled to the microprocessor and configured to store compensation data, wherein
• the at least one amplifier stage of the oscillation amplifier includes a controllable temperature compensation circuit configured to influence an oscillation behavior of the oscillator based on compensation values, as control data, from the microprocessor or from the storage medium, depending on the temperature detected by the temperature sensor, and
• the temperature compensation circuit comprises an operational amplifier configured as a voltage follower and for decoupling the microprocessor from the oscillator amplifier, and
• the microprocessor is configured to receive the temperature detected by the temperature sensor, generate the control data based on the temperature and the compensation data, and forward the control data to the temperature compensation circuit.