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:
Dec. 19, 2000
Filed:
Jul. 08, 1998
Daniel Nepela, San Jose, CA (US);
Chung F Lam, San Jose, CA (US);
Read Rite Corporation, Fremont, CA (US);
Abstract
A magnetoresistive head achieves maximum signal output with minimal electromigration by using a magnetoresistive element through which a unidirectional sense current is flown. Periodically, a control circuit determines whether one or more switching criteria have been met, and applies a counter-directional compensation current in the magnetoresistive element when the switching criteria are met, thus suppressing electromigration in the magnetoresistive element in the direction of said sense current. In a preferred embodiment, the compensation current is applied during a quiescence period. In another embodiment a continuous unidirectional sense current is flown through the magnetoresistive element, and the control circuit suspends the sense current in the magnetoresistive element for a period of time when one or more switching criteria have been met, so as to prevent atomic excursion beyond one atomic diameter, such that electromigration in the magnetoresistive element is substantially reduced in the direction of the sense current.