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:
Jul. 03, 2001
Filed:
May. 12, 1999
Andrew David Brown, Bristol, GB;
Simon John Chandler, Bristol, GB;
Hewlett-Packard Company, Palo Alto, CA (US);
Abstract
A method is described of calibrating a write pre-equalization circuit in the write channel of a magnetic data storage device which maximizes the rate at which the write channel can write to a data storage medium. The method includes the steps of: setting an amplitude of a delayed current to a minimum value ; setting a delay period of the delayed current to a minimum value; setting an amplitude of a main driver current to a minimum value; recording a low frequency test signal to the data storage medium; reading the low frequency test signal from the data storage medium; monitoring a quality metric of the low frequency test signal; varying the amplitude of the main driver current over a range of amplitudes; selecting an optimum amplitude of the main driver current; setting the delay period of the delayed signal to a predetermined value; recording a pseudo-random test signal to the data storage medium; reading the pseudo-random test signal from the data storage medium; monitoring a quality metric of the read pseudo-random test signal; varying the amplitude of the delayed current over a range of amplitudes; and selecting an optimum value of the delayed current, depending on the monitored quality metric.