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:
May. 06, 2008
Filed:
Dec. 21, 2005
Dean V. Dang, Amphur Prakret, TH;
Philip Bernard Saram, Kuala Lampur, SG;
Chakrit Choosang, Bangkae, TH;
Jonas A. Goode, Lake Forest, CA (US);
Dean V. Dang, Amphur Prakret, TH;
Philip Bernard Saram, Kuala Lampur, SG;
Chakrit Choosang, Bangkae, TH;
Jonas A. Goode, Lake Forest, CA (US);
Western Digital Technologies, Inc., Lake Forest, CA (US);
Abstract
A disk drive is disclosed comprising a disk having top and bottom surfaces, and top and bottom heads actuated over the top and bottom surfaces, respectively. Control circuitry detects a warping of the disk by writing a first test pattern to the top surface, reading the first test pattern to generate a first read signal, monitoring a first read signal value proportional to an amplitude of the first read signal, writing a second test pattern to the bottom surface, reading the second test pattern to generate a second read signal, monitoring a second read signal value proportional to an amplitude of the second read signal, and processing the first and second read signal values to detect a negative correlation between the amplitudes of the first and second read signals.