Patent ID: 7504824

Claim:
A magnetic field sensor for measuring an external magnetic field, comprising: a mechanism to generate a first offset magnetic field; a first magnetoresistive-layered structure having an electrical resistance depending on a magnitude of a first magnetic field, the first magnetic field comprising components of the external magnetic field and components of the first offset magnetic field; a second magnetoresistive-layered structure, the first and the second magnetoresistive layered structures arranged in a first bridge circuit and exhibiting a magnetoresistive effect; a third magnetoresistive-layered structure and a fourth magnetoresistive-layered structure, the first, the second, the third, and the fourth magnetoresistive-layered structures arranged in the first bridge structure, and the third and the fourth magnetoresistive-layered structures comprising a soft magnetic element adapted to screen at least one of the external magnetic field and the first offset magnetic field; a first soft magnetic planar structure and a second soft magnetic planar structure separated from one another by a first elongated gap, the first magnetoresistive-layered structure positioned along the first elongated gap; and, a fifth magnetoresistive-layered structure and a sixth magnetoresistive-layered structure, and a third soft magnetic planar structure and a fourth soft magnetic planar structured separated from one another by a second elongated gap, a direction of the second elongated gap substantially perpendicular to a direction of the first elongated gap, the fifth and the sixth magnetoresistive-layered structures positioned along the second elongated gap and arranged in a second bridge circuit, wherein the mechanism is adapted to further generate a second offset magnetic field, the second offset magnetic field substantially anti-parallel to the first offset magnetic field, the first and the second offset magnetic fields having substantially equal magnitude.