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:
Oct. 19, 1999
Filed:
Nov. 14, 1997
Paul Wingshing Chung, San Jose, CA (US);
John Thomas Contreras, San Jose, CA (US);
Klaas Berend Klaassen, San Jose, CA (US);
Calvin Shizuo Nomura, San Jose, CA (US);
International Business Machines Corporation, Armonk, NY (US);
Abstract
A method and apparatus for re-initializing a GMR head after losing initialization is disclosed. The invention may use a voltage controlled waveform, which allows the current to vary with the resistance of the GMR head. Furthermore, according to a further aspect of the invention a stack of GMR heads may be reinitialized having the same orientation to preclude inversion of the reset magnetic fields on half of the heads. In addition, improvements in re-initializing GMR heads is provided by implementing wave shaping. The invention can also provide re-initialization of GMR heads at different points in the manufacturing process.