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. 24, 2010
Filed:
Dec. 28, 2005
Applicant:
Katashi Hasegawa, Kasugai, JP;
Inventor:
Katashi Hasegawa, Kasugai, JP;
Assignee:
Fujitsu Semiconductor Limited, Yokohama, JP;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
H03L 7/093 (2006.01);
U.S. Cl.
CPC ...
Abstract
A low pass filter can be built in a chip by reducing the value of circuit element forming a low pass filter in a PLL circuit, especially by reducing the value of a electrostatic capacity. An active filter used in a PLL circuit having two charge pump circuits in a subsequent stage of a phase comparator includes a first circuit component connected between the output of one charge pump circuit and a ground, a second circuit component between the output of another charge pump circuit and the ground, and a voltage adder for adding up voltages between both ends of each of the first and second circuit components.