Patent ID: 7573684

Claim:
An apparatus comprising: a first current-in-plane sensor including first and second layers of ferromagnetic material, and a first layer of non-magnetic material positioned between the first and second layers of ferromagnetic material, wherein the thickness of the first layer of non-magnetic material is selected to provide antiferromagnetic coupling between the first and second ferromagnetic layers; a first magnetic field source for biasing the first and second layers of ferromagnetic material in the first current-in-plane sensor in a first direction; a second current-in-plane sensor positioned parallel to the first current-in-plane sensor including third and fourth layers of ferromagnetic material, and a second layer of non-magnetic material positioned between the third and fourth layers of ferromagnetic material, wherein the thickness of the second layer of non-magnetic material is selected to provide antiferromagnetic coupling between the first and second ferromagnetic layers; a second magnetic field source for biasing the third and fourth layers of ferromagnetic material in the second current-in-plane sensor in a second direction; and first and second electrodes for supplying sense current to the first and second current-in-plane sensors.