The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Sep. 25, 2001
Filed:
Dec. 22, 1998
Isamu Tomita, Kawasaki, JP;
Takao Koshikawa, Kawasaki, JP;
Toshinori Hoshino, Kawasaki, JP;
Tadashi Nakamura, Kawasaki, JP;
Hitoshi Kanai, Kawasaki, JP;
Hiroaki Ueno, Kawasaki, JP;
Fujitsu Limited, Kawasaki, JP;
Abstract
When a pin layer magnetic field offset judgment unit judges that a magnetic field in a pin layer of a spin valve head through which a sense current flows in the interference direction has been deviated from a normal direction, a recovery processing unit allows a recovery from the abnormality arising from the magnetic field offset. For example, the direction of the sense current is switched from the interference direction to the assist direction, and the sense current larger than that upon the ordinary reading action is allowed to flow so that the temperature of an antiferromagnetic layer exceeds the blocking temperature, whereby the direction of the magnetic field in the pin layer is modified to the normal direction by the action of a magnetic field generated from the sense current. After the modification, the sense current is returned to have its ordinary value in the interference direction.