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:
Oct. 15, 1991
Filed:
Feb. 26, 1991
Applicant:
Inventor:
Cheng C Shih, Rancho Cordova, CA (US);
Assignee:
Level One Communications, Inc., Folsom, CA (US);
Primary Examiner:
Int. Cl.
CPC ...
H03L / ;
U.S. Cl.
CPC ...
331 / ; 331 17 ; 375120 ;
Abstract
An all-digital phase-locked loop (ADPLL) is disclosed having a wide bandwidth while maintaining relatively small steps for phase error correction. A random walk filter with memory and a pattern sensitive phase adjustment circuit cooperate to control the ADPLL frequency/phase adjustment rate by taking multiple, relatively smnall steps in phase error correction at fixed intervals of time. A short cycle occurs when the phase disparity is large, interrupting the execution of the fixed interval cycle expediting the ADPLL phase lock time without sacrificing resolution in the phase error correction steps.