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:
Sep. 30, 2003
Filed:
Oct. 11, 2000
Applicant:
Inventor:
Hai T. Ho, Westminster, CO (US);
Assignee:
Seagate Technoogy LLC, Scotts Valley, CA (US);
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
G11B 5/596 ;
U.S. Cl.
CPC ...
G11B 5/596 ;
Abstract
A method and apparatus are provided for generating a feedforward cancellation signal for a next sector of a disc in a disc drive. To form the cancellation signal, the method and apparatus generate a trigonometric value having the phase and frequency of a nonrepeatable runout error by passing a position error signal through a phase lock loop. An amplitude is determined for the cancellation signal based on the position error signal. The amplitude is then multiplied by the trigonometric value to from the cancellation signal.