Magnetic field sensor with magnetoresistance elements and conductive-trace magnetic source

摘要

In an embodiment, a magnetic field sensor comprises a substrate and a first magnetoresistive element supported by the substrate. The magnetic field sensor also includes a second magnetoresistive element supported by the substrate and coupled in series with the first magnetoresistive element to form a voltage node between the first and second magnetoresistive elements, and at which an output voltage is provided that changes in response to an external magnetic field. The magnetic field sensor also includes a magnetic source that produces a local magnetic field having a strength sufficient to bias the first magnetoresistive element to a resistive value that is substantially resistant to changing in response to the external magnetic field. In embodiments, additional magnetoresistive elements are included to form an H-bridge circuit.