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. 08, 2003
Filed:
Aug. 31, 2000
Raffi Codilian, Irvine, CA (US);
Hanan Kupferman, Diamond Bar, CA (US);
Yoo H. Kim, Laguna Niguel, CA (US);
Western Digital Technologies, Inc., Lake Forest, CA (US);
Abstract
The present invention may be embodied in a method, and related apparatus, for determining a repeatable runout (RRO) compensation value set for a track on a disk in a disk drive, wherein the disk drive is initially manufactured and then shipped for installation in a host system. The track comprises a plurality of embedded servo sectors that define a circumferential path having RRO which requires compensation during track following. The method comprises determining a first RRO compensation value set for the track to a first desired learning level by measuring the RRO for the track based on a first predetermined number of disk rotations during the initial manufacturing of the disk drive. Then, after the disk drive is shipped for installation in the host system, determining a second RRO compensation value set for the track to a second desired learning level by measuring the RRO for the track based on at least a second predetermined number of disk rotations, wherein the second predetermined number of disk rotations is greater than the first predetermined number of disk rotations. The learning technique of the invention allows the disk drive to be shipped for installation in a host system with a portion of its tracks having little or no RRO compensation. After shipment, the disk drive may continue to improve the RRO compensation until all of the tracks have been optimally compensated. Thus, the learning technique allows maintained manufacturing throughput without unnecessarily increasing manufacturing costs for high data storage capacity disk drives.