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:
Dec. 27, 2011
Filed:
Mar. 19, 2007
Applicants:
Haruo Taguchi, Kyoto, JP;
Hidekazu Kojima, Kyoto, JP;
Inventors:
Haruo Taguchi, Kyoto, JP;
Hidekazu Kojima, Kyoto, JP;
Assignee:
Rohm Co., Ltd., Kyoto, JP;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
G06F 3/038 (2006.01); H03L 7/06 (2006.01);
U.S. Cl.
CPC ...
Abstract
In a negative step-up charge pump circuit according to the present invention, of a plurality of stages of charge transfer transistors and an output transistor, the former-stage transistors are P channel type field effect transistors, and the later-stage transistors are N channel type field effect transistors. With such configuration, it is possible to avoid start-up failure and current driving performance deterioration resulting from an increase in the number of stages of step-up units without complicating processes and increasing the chip size.