Apparatus and method for magnetic sensor output compensation based upon ambient temperature

1. A circuit, comprising:

a magnetic sensor that produces an uncompensated magnetic sensor output signal;

a temperature sensor that produces an ambient temperature signal; and

a compensation circuit connected to the magnetic sensor and the temperature sensor, the compensation circuit configured to add a computed temperature compensation signal to the uncompensated magnetic sensor output signal to produce a magnetic sensor temperature compensated output signal that reduces thermally induced variation of the uncompensated magnetic sensor output signal, wherein the compensation circuit forms the computed temperature compensation signal as a function of the ambient temperature signal, a room temperature signal, a room temperature coefficient gain signal, a temperature coefficient gain signal and the uncompensated magnetic sensor output signal.

2. The circuit of claim 1 wherein the compensation circuit computes a temperature differential signal based upon a difference between the ambient temperature signal and the room temperature signal.

3. The circuit of claim 2 wherein the compensation circuit computes a gain ratio signal based upon the temperature coefficient gain signal divided by the room temperature coefficient gain signal.

4. The circuit of claim 3 wherein the compensation circuit multiplies the gain ratio signal and the temperature differential signal to form a gain variation signal.

5. The circuit of claim 4 wherein the compensation circuit multiplies the gain variation signal by the uncompensated magnetic sensor output signal to form the computed temperature compensation signal.