The differential Hall sensor IC detects the motion of tooth and magnet encoder applications. To detect the motion of ferromagnetic objects, the magnetic field must be provided by a back biasing permanent magnet. Either south or north pole of the magnet can be attached to the rear unmarked side of the IC package.The magnetic measurement is based on three equally spaced Hall elements, integrated on the IC. Both magnetic and mechanical offsets are cancelled by a self calibration algorithm. The sensor includes a current output PWM protocol.