MAGNETORESISTIVE SENSOR WITH STRAY FIELD CANCELLATION AND SYSTEMS INCORPORATING SAME

A system includes a magnetic sense element for detecting an external magnetic field along a sensing axis and a magnetic field source proximate the magnetic sense element for providing an auxiliary magnetic field along the sensing axis, the auxiliary magnetic field being a high frequency periodic signal. The magnetic sense element produces a first output signal having a magnetic field signal component, responsive to the external magnetic field, that is modulated by an auxiliary magnetic field signal component responsive to the auxiliary magnetic field. A processing circuit identifies from the first output signal an influence of a magnetic interference field on the auxiliary magnetic field signal component, the magnetic interference field being directed along a non-sensing axis of the magnetic sense element, and applies a correction factor to the magnetic field signal component to produce a second output signal in which the influence of the magnetic interference field is substantially removed.