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:
Aug. 07, 2007
Filed:
Jan. 06, 2005
Nobuhisa Koide, Kanagawa, JP;
Yukiko Hayashi, Kanagawa, JP;
Shougo Shimada, Kanagawa, JP;
Gaku Ikedo, Kanagawa, JP;
Nobuhisa Koide, Kanagawa, JP;
Yukiko Hayashi, Kanagawa, JP;
Shougo Shimada, Kanagawa, JP;
Gaku Ikedo, Kanagawa, JP;
Hitachi Global Storage Technologies Netherlands B.V., Amsterdam, NL;
Abstract
Embodiments of the invention provide a way to accurately detect the position of a spindle motor. In a spindle motor startup process according to one embodiment, a parameter setup section acquires from a parameter table a sense time value corresponding to an input voltage that is acquired from an ADC. The parameter setup section sets the sense time value in a register. A position determination section, which is within an SPM driver, performs an induced voltage detection process for rotor position detection purposes during the time corresponding to the sense time value that is set in the register. Even when the input voltage is decreased, rotor position detection can be properly achieved by changing the sense time value in accordance with a change in the input voltage.