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:
Mar. 09, 2004
Filed:
Jul. 10, 1998
Applicant:
Inventors:
Assignee:
Tellabs Operations, Inc., Lisle, IL (US);
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
H03D 3/24 ; H03L 2/700 ;
U.S. Cl.
CPC ...
H03D 3/24 ; H03L 2/700 ;
Abstract
An improved phase-lock loop circuit comprising a phase detector, a loop filter, and a voltage controlled oscillator. The phase detector samples the phase-lock loop input signal at various points in a cycle of the phase-lock loop output signal and outputs a signal representative of the point of the phase-lock loop output cycle at which a logic state transition of the input signal is detected. In addition, a self-sweeping autolock circuit interacts with the loop filter in such a manner that the self-sweeping autolock circuit commands the loop filter to sweep its output signal when phase-lock is absent and the loop filter halts the sweep of its output signal when phase-lock is acquired.