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:
Jul. 29, 2014
Filed:
Jul. 22, 2010
Junji Nishida, Neyagawa, JP;
Junji Nishida, Neyagawa, JP;
Ricoh Company, Ltd., Tokyo, JP;
Abstract
A charge pump circuit which steps down an input voltage inputted from an input terminal and outputs it as a step-down output voltage from a step-down output terminal, and steps up the input voltage and outputs it as a step-up output voltage from a step-up output terminal, includes: a voltage conversion circuit having a flying capacitor, a step-down output capacitor, a step-up output capacitor, and a plurality of switches, wherein the flying capacitor, the step-down output capacitor, the step-up output capacitor, and the switches are connected, and the voltage conversion circuit is capable of switching connection states by switching each on/off state of the switches; an output voltage detection circuit unit which makes a comparison of a voltage between the step-down output voltage and a first predetermined voltage, and makes a comparison of a voltage between the step-up output voltage and a second predetermined voltage, and produces and outputs each signal indicating each result of the comparisons; and a control circuit unit which performs a switching control depending on each signal outputted from the output voltage detection circuit unit.