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:
Nov. 20, 2012
Filed:
Sep. 01, 2008
Shuji Nishi, Osaka, JP;
Sachio Tsujino, Osaka, JP;
Yuhichiroh Murakami, Osaka, JP;
Yasushi Sasaki, Osaka, JP;
Seijirou Gyouten, Osaka, JP;
Shuji Nishi, Osaka, JP;
Sachio Tsujino, Osaka, JP;
Yuhichiroh Murakami, Osaka, JP;
Yasushi Sasaki, Osaka, JP;
Seijirou Gyouten, Osaka, JP;
Sharp Kabushiki Kaisha, Osaka, JP;
Abstract
An embodiment of the present invention provides a power supply circuit including a charge-pumping booster section which uses switching elements provided only by N-channel transistors yet does not have a problem of voltage drop by threshold value. When a boosted voltage is obtained at a first terminal of a first capacitor in a booster section, a booster control section supplies this boosted voltage to a third capacitor, to boost the voltage further thereby turning ON a first transistor. When a boosted voltage is obtained at a first terminal of a second capacitor in the booster section, the booster control section supplies this boosted voltage to a fourth capacitor, to boost the voltage further thereby turning ON a second transistor. This arrangement eliminates a problem of voltage drop by threshold value in the first and the second transistors which serve as output-side switching elements.