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. 11, 1994
Filed:
Apr. 12, 1991
Ronald E Wilson, Lake Forest, CA (US);
Karl M Lofgren, Newport Beach, CA (US);
Western Digital Corporation, Irvine, CA (US);
Abstract
A phase-locked system for recovering data from a disk drive includes a phase detector for signalling the difference in phase between incoming delayed data pulses and a phase detection window clock signal. The phase detection window clock signal is derived from one output of an integrated-circuit window generator, driven by the output of a voltage-controlled oscillator whose frequency is controlled by the phase detector. The phase-locked loop is completed by comparing the phase detection window clock signal output of the window generator with the incoming delayed data pulses in the phase detector. Data detection window clock pulses, defining time windows in which the delayed data pulses are exactly centered, are produced at a second output of the window generator which has a line about which it is essentially symmetric, resulting in the two outputs of the window generator being exactly 180.degree. apart in phase from each other.