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:
Feb. 09, 2010
Filed:
Jul. 30, 2008
Applicant:
Yoshiyasu Doi, Kawasaki, JP;
Inventor:
Yoshiyasu Doi, Kawasaki, JP;
Assignee:
Fujitsu Limited, Kawasaki, JP;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
H03L 7/06 (2006.01);
U.S. Cl.
CPC ...
Abstract
A charge pump circuit comprises two MOS transistors serially connected between a power supply voltage VDD and ground, a switch SW, four switches SWthrough SW, four capacitors Cthrough C, and four switches SWthrough SW. If a control voltage Vcntl is to be varied, a specific switch SW of the switches SWthrough SWis turned on such that a specific capacitor is charged to the power supply voltage VDD. Then, a specific switch SW of the switches SWthrough SWis turned on to transfer the electric charge stored in the capacitor to the capacitor of a low-pass filter and thereby the control voltage is controlled at a desired value.