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:
Aug. 29, 2000
Filed:
Jun. 25, 1998
Applicant:
Inventor:
Hideaki Tanishima, Kasugai, JP;
Assignee:
Fujitsu Limited, Kanagawa, JP;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
H03L / ;
U.S. Cl.
CPC ...
331 17 ; 331 25 ; 327148 ;
Abstract
A charge pump circuit which may be used in a PLL includes a charge/discharge circuit, a detection circuit and an adjusting circuit. The charge/discharge circuit performs a charge operation in response to a first pulse signal and a discharge operation in response to a second pulse signal and outputs an output signal having a voltage based on the charge and the discharge operations. The detection circuit detects whether a charge operation or a discharge operation was performed and generates a control signal. The adjusting circuit adjusts the charge and discharge operations so that a charge amount and a discharge amount per unit time become substantially equal to each other.