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:
Nov. 30, 1999
Filed:
Jul. 29, 1997
International Business Machines Corporation, Armonk, NY (US);
Abstract
A motor having enhanced transient characteristics during the acceleration time of the motor in a disk unit. The motor includes a motor controller having a phase-locked loop (PLL) or frequency-locked loop (FLL) for controlling the speed of a spindle motor in a disk drive. The PLL or FLL is coupled to a digital filter. The difference between a phase or frequency synchronized with the rotational speed of the motor and a target value is received by the digital filter. The digital filter output is added to the target value. The sum of the filter output and the target value is set in the PLL or FLL as an adjusted target value to perform PLL control or FLL control. With this arrangement, the time to shift from a low-speed rotation state to a high-speed rotation state can be shortened.