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. 10, 2007
Filed:
Jul. 29, 2004
Applicants:
Yuji Sakai, Ome, JP;
Kazuhito Shimomura, Fussa, JP;
Inventors:
Yuji Sakai, Ome, JP;
Kazuhito Shimomura, Fussa, JP;
Assignee:
Kabushiki Kaisha Toshiba, Tokyo, JP;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
G11B 5/09 (2006.01);
U.S. Cl.
CPC ...
Abstract
In a disk drive that performs perpendicular magnetic recording, the read/write channel has a sync mark generator. The sync mark generator generates a second sync mark before the read/write channel operates to write data on a disk. The second sync mark has a bit pattern including a series of bits representing positive polarity and a series of bits representing negative polarity. The series of bits, which is longer than the other, has a bit length that is at least 50% but less than 85% of the total bit length of the second sync mark.