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:
Jul. 11, 2000
Filed:
Oct. 06, 1998
Applicant:
Inventors:
Assignee:
Fujitsu Limited, Kanagawa, JP;
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
H03L / ;
U.S. Cl.
CPC ...
327156 ; 327159 ; 375360 ; 375375 ;
Abstract
A digital PLL circuit recovers a clock signal from an analog baseband signal. The PLL circuit has a phase comparator. The phase comparator provides a loop filter with a control value for a period of the recovered clock signal after a determination is made. If the determination is that the baseband signal has crossed a transition level, the control value corresponds to a time difference between a sampling point and a transition-level crossing point of the baseband signal. If the determination is that the baseband signal has not crossed the transition level, the control value is 0. The PLL circuit shortens a lockup time and provides stable operation even if the baseband signal involves an offset.