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:
Apr. 23, 2002
Filed:
Nov. 08, 1999
David A. Freitas, Morgan Hill, CA (US);
International Business Machines Corp., Armonk, NY (US);
Abstract
A method and apparatus for improving baseline recovery of an MR head using a programmable AC coupling pole. The location of the pole may be adjusted to achieve the fastest recovery from a baseline shift without degrading the normal channel performance. Further, the pole may be moved during the data recovery procedure to recover from a data read error. The programmable AC coupling pole includes a circuit path carrying digital data signals read from a recording media by a magnetic head, an amplifier coupled to the circuit path for amplifying the digital data signals, and a recovery time setting device having an programmable recovery time constant associated therewith. Once a data read error has been detected by the system, the recovery time constant may be adjusted to set a recovery time for the amplifier to provide readable data signals. In addition, a digital controller may be coupled to the recovery time setting device for adjusting the recovery time setting device to change the recovery time constants in response to disturbances to the magnetic head. The programmable AC coupling pole may be disposed at the output of the magnetic head preamplifier or it may be before the data channel amplifier.