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:
Sep. 15, 1998
Filed:
Jun. 24, 1996
Applicant:
Inventor:
Kadaba R Lakshmikumar, Basking Ridge, NJ (US);
Assignee:
Lucent Technologies Inc., Murray Hill, NJ (US);
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
H04L / ;
U.S. Cl.
CPC ...
375376 ; 329303 ; 329307 ; 331 / ; 331 / ;
Abstract
A digital phase detector which generates low jitter when the phase-locked-loop is in lock. A delay line, combined with an UP/DOWN phase detector causes substantial overlap in the UP and DOWN signals from the detector. When the PLL is in lock, the overlapping signals substantially cancel each other out, minimizing the variations in the output frequency. Two approaches are disclosed: one delaying the UP signal sufficiently to overlap the DOWN signal, the other using a delay and an exclusive OR gate to generate the DOWN signal.