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:
Jul. 14, 1998
Filed:
May. 01, 1996
Me Van Le, Milpitas, CA (US);
Jong-Ming Lin, Cupertino, CA (US);
Samsung Electronics, Ltd., Suwon, KR;
Abstract
A method and apparatus for generating servo information used in positioning the read head of a hard disk drive. The apparatus comprises a disk having a plurality of tracks, at least one of which has a servo field which includes four servo bits: an A bit, a B bit, a C bit and a D bit, where the A bit and the B bit have a common boundary located at the track centerline and where the C bit and the D bit have a common boundary. A servo signal based on the four servo bits is generated and used to position the head relative to a track of the disk. A servo signal may be generated from the sum of the difference between the A and B bits, and the difference between the C and D bits. An offset may be used to eliminate phase errors introduced into the servo signal. The offset may be representative of the magnitude of the difference between the C and D bits. The servo signal may also be generated from the difference of the difference between the A and B bits, and the difference between the C and D bits.