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:
Dec. 01, 2009
Filed:
Jan. 15, 2008
Takashi Konishi, Kanagawa, JP;
Takashi Konishi, Kanagawa, JP;
Hitachi Global Storage Technologies Netherlands B.V., Amsterdam, NL;
Abstract
Embodiments of the present invention provide a data recording device capable of achieving desired performance while increasing the convergence rate. According to one embodiment, in a data recording device, an update-width determination unit included in a setting updating unit determines an update-width of a set frequency f in a digital filter according to the size of a position error signal PES, and an update-width adjuster included in the setting updating unit changes the update-width of the set frequency f determined by the update-width determination unit according to the size of the set frequency f. Thus, while the convergence rate being kept properly, the set frequency f can precisely be converged on a frequency of a disturbance component.