Abstract: A proximity sensor or switch having a sensing coil, an oscillator connected to the coil, a comparator connected to the oscillator, a reference voltage module connected to the comparator, and an output driver connected to the comparator. The voltage module may incorporate a resistor having an end connected to a high side of a power source, and a digital potentiometer having a first end connected to another end of the resistor and to the comparator, and having a second end connected to a ground side of the power source. The digital potentiometer may have a resistance that is varied with a signal. A variation of the resistance for the digital potentiometer may result in a change of a voltage from the reference voltage module which further changes a switching distance of the proximity switch to a predetermined value.

Abstract: An apparatus comprises: a first comparator configured to: receive an input proximity signal indicating a proximity of a target device, receive a second reference signal associated with a second distance, make a first comparison of the input proximity signal to the second reference signal, and provide a first output proximity signal based on the first comparison; and a second comparator configured to: receive the input proximity signal, receive the first output proximity signal, make a second comparison of the input proximity signal using the first output proximity signal, and provide a second output proximity signal based on the second comparison.

Abstract: A proximity sensor or switch having a sensing coil, an oscillator connected to the coil, a comparator connected to the oscillator, a reference voltage module connected to the comparator, and an output driver connected to the comparator. The voltage module may incorporate a resistor having an end connected to a high side of a power source, and a digital potentiometer having a first end connected to another end of the resistor and to the comparator, and having a second end connected to a ground side of the power source. The digital potentiometer may have a resistance that is varied with a signal. A variation of the resistance for the digital potentiometer may result in a change of a voltage from the reference voltage module which further changes a switching distance of the proximity switch to a predetermined value.

Abstract: An apparatus comprises: a first comparator configured to: receive an input proximity signal indicating a proximity of a target device, receive a second reference signal associated with a second distance, make a first comparison of the input proximity signal to the second reference signal, and provide a first output proximity signal based on the first comparison; and a second comparator configured to: receive the input proximity signal, receive the first output proximity signal, make a second comparison of the input proximity signal using the first output proximity signal, and provide a second output proximity signal based on the second comparison.