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:
May. 01, 1990
Filed:
Jun. 03, 1988
Applicant:
Inventors:
Karl M Lofgren, Long Beach, CA (US);
Gerald W Shearer, Orange, CA (US);
Kenneth W Ouyang, Huntington Beach, CA (US);
Assignee:
Western Digital Corporation, , CA (US);
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
H03K / ; H03K / ;
U.S. Cl.
CPC ...
307595 ; 307511 ; 307597 ; 307602 ; 307603 ; 328 55 ; 328155 ;
Abstract
A circuit for providing precise delays includes a phase-locked loop driven by a reference frequency source such as a crystal oscillator and including a variable delay circuit. The output of the oscillator is applied to the delay circuit and the non-delayed and delayed signals are compared in a phase comparator. An error signal representative of phase error is developed and applied to vary the amount of delay until the phase error is eliminated. A precise delay referenced to the oscillator frequency is therefore achieved.