Patent ID: 6775109
Filing Date: 2004-08-10
Classification: B82Y,G01R,G11B,Y10T

Abstract:
An apparatus for sensing an external magnetic field by the giant magnetoresistive effect comprising:a substrate; a plurality of magnetic stripes fanned over the substrate, each of the plurality of magnetic stripes having a length with respective ends and a cross-sectional area of less than 1000 Ã¥2, the plurality of magnetic stripes being spaced apart side by side over the substrate such that stray magnetic fields at the ends of the plurality of magnetic stripes provide a magnetostatic coupling to the ends of adjacent magnetic swipes whereby alternating magnetic stripes within the plurality of magnetic stripes are magnetized in alternating directions at times an external magnetic field is below a first value; a nonmagnetic conductive material fanned within a plurality of spaces interposed between the plurality of magnetic stripes to form a conductive path through the plurality of stripes in series; and means for detecting a change in resistance through the plurality of magnetic stripes in series as a function of a second value of the external magnetic field applied to the plurality of magnetic stripes above the first value of the magnetic field, where the second value of the magnetic field aligns the magnetizations of the plurality of magnetic snipes in the same direction.