Abstract: A temperature compensated Hall-effect sensor apparatus is disclosed which senses the position of a moving body and provides an output signal indicative of the position of the moving body. The apparatus includes a Hall device which senses the application and subsequent removal of a magnetic field and provides an output signal to a constant gain amplifier. Circuitry is provided in the constant gain amplifier for adjusting the gain of the amplifier and also for nulling-out any offset voltage received from the Hall device. The output of the constant gain amplifier is input to a sensitivity compensation and hysteresis circuit for setting a positive-going threshold trip level and a negative-going threshold trip level into a comparator.