Omnipolar Schmitt Trigger

A sensor comprising:

• a magnetic field sensing element configured to generate a magnetic field signal in response to a sensed magnetic field;
• a
• a switching circuit coupled to receive the magnetic field signal and generate a switching signal that changes a polarity of the magnetic field signal at a predetermined frequency;
• and
• a comparison device coupled to receive the switching signal and generate an output signal that changes a level in response to the switching signal crossing a predetermined threshold, wherein the output signal is independent of the polarity of the magnetic field signal and wherein the predetermined threshold is the same regardless of the polarity of the magnetic field signal.

A sensor comprising:

• means for generating a magnetic field signal indicative of a distance or an angle between the generating means and a target;
• means for switching a polarity of the magnetic field signal at a predetermined frequency to generate a switching signal;
• and
• means for comparing the switching signal to a predetermined threshold to generate an output signal that changes a level in response to the switching signal crossing the predetermined threshold, wherein the output signal is coupled to the switching means to stop the switching means changing the polarity of the magnetic field signal in response to the level of the output signal.