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:
Jan. 23, 2001
Filed:
Dec. 15, 1998
Shaibal Barua, Dallas, TX (US);
William R. Krenik, Garland, TX (US);
Texas Instruments Incorporated, Dallas, TX (US);
Abstract
A circuit and method for braking a disk drive when a power fault occurs has a circuit (,) for producing an output signal (,) indicating that the motor of the disk drive has slowed at least to a predetermined rotational speed after the occurrence of the power fault. The components of the circuit (,) may be integrated onto the same integrated circuit as the motor driving circuitry or head retract circuitry. During the time between the occurrence of the power fault and the time the disk drive has slowed to the predetermined rotational speed, the read/write head mechanism (,) is retracted. A braking circuit then brakes the disk drive when the output signal (,) indicates that the motor has slowed, at least to the predetermined rotational speed. The circuit for producing an output signal indicating that the motor has slowed at least to the predetermined rotational speed is actuated by the back-emf (,) generated by the motor failing below a predetermined level.