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. 20, 2003
Filed:
Nov. 19, 1999
Kok-Kia Chew, Fremont, CA (US);
Gerald Keith Lunn, San Jose, CA (US);
Cirrus Logic, Inc., Austin, TX (US);
Abstract
There is a need for low-cost and reliable shock-sensing methods in magnetic hard-disk drives to maintain data integrity when a drive is subjected to external shocks. The present invention uses a novel shock-sensing method that is both reliable and low-cost, using a modified head preamplifier to detect servo fields from adjacent disk surfaces, as well as the disk surface being written or read. Servo fields on adjacent surfaces may be staggered. When a write head is writing data to a data field on a disk surface, a read head may be reading a servo field from an adjacent surface, insuring that the write head is on-track. By staggering the servo fields from surface to surface, shock may be sensed by measuring displacement of read heads on adjacent surfaces between servo sectors on the write surface. In addition, the use of a shock sensor or the like may be eliminated, reducing drive component cost.