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:
Jan. 11, 2011
Filed:
Aug. 15, 2008
Man Cheung, Campbell, CA (US);
Perry Neos, Los Altos, CA (US);
David Rutherford, San Jose, CA (US);
Marvell International Ltd., Hamilton, BM;
Abstract
A recording medium can include multiple helicoid patterns arranged in multiple helicoid groups, e.g., first and second helicoid groups. Operating a disk drive can include switching between helicoid groups to maintain the alignment of the head with respect to a target track of the rotating recording medium. Enabling a switch can include receiving a waveform produced by a head operated with respect to a rotating recording medium, generating first information from one or more portions of the waveform corresponding to the helicoid patterns of the first helicoid group; generating second information from one or more portions of the waveform corresponding to the helicoid patterns of the second helicoid group; and analyzing the second information with respect to the first information to generate calibration information. The calibration information can compensate for operational differences between using the helicoid patterns of the first helicoid group and the helicoid patterns of the second helicoid group.