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:
Oct. 02, 2012
Filed:
Dec. 05, 2008
Yohichi Shiwaya, Osaka, JP;
Yohichi Shiwaya, Osaka, JP;
Ricoh Company, Ltd., Tokyo, JP;
Abstract
A power supply circuit includes a charge pump circuit configured to raise a voltage inputted from an input terminal and supply the raised voltage from an output terminal to a given load and a control circuit unit. The charge pump circuit includes a fly-back capacitor configured to store a charge of the voltage inputted from the input terminal and an output transistor connected between one terminal of the fly-back capacitor and the output terminal of the charge pump circuit. The control circuit unit receives a reference voltage and the voltage outputted from the charge pump circuit and is configured to generate a proportional voltage proportional to the voltage outputted from the charge pump circuit and output a voltage to control the output transistor depending on a difference between the proportional voltage and the reference voltage so that the proportional voltage has the same voltage level as the reference voltage.