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:
Jan. 29, 2008
Filed:
Dec. 21, 2004
Kuan-yeu Chen, Hsinchu, TW;
Yi-ti Wang, Hsinchu, TW;
Kuan-Yeu Chen, Hsinchu, TW;
Yi-Ti Wang, Hsinchu, TW;
Macronix International Co., Ltd., Hsinchu, TW;
Abstract
A charge pump circuit comprises a first pump stage, including a first sub-pump coupled to a first pre-charge MOSFET transistor, wherein the first sub-pump is used to pump down a gate of the first pre-charge MOSFET transistor to thereby increase the pre-charge efficiency of the first pre-charge MOSFET transistor. The higher efficiency the pre-charge MOSFET is, the lower the gate level of a pass transistor is. Thus, the charge sharing efficiency becomes better, and the body effect will be eliminated. The following pump stage is the same as the first pump stage. In addition, this pre-charging is implemented by PMOSFET only; therefore, only a single well is needed and then a small layout area can be achieved. Consequently, a high efficiency negative pump can be obtained.