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:
Aug. 14, 2012
Filed:
Mar. 05, 2009
Kuniaki Arai, Tokyo, JP;
Kuniaki Arai, Tokyo, JP;
Ricoh Company, Ltd., Tokyo, JP;
Abstract
In a charging control circuit for controlling charging of a secondary battery, a charging transistor generates a charging current according to a control signal input to a control electrode and outputs the charging current to the secondary battery. The proportional current generation transistor generates and outputs a proportional current proportional to the charging current output by the charging transistor. The constant current charging controller controls the charging transistor so that the proportional current generated by the proportional current generation transistor attains a predetermined first value. The constant current charging controller controls a voltage of a current output terminal of the proportional current generation transistor so that a voltage difference between the voltage of the current output terminal of the proportional current generation transistor and a voltage of a current output terminal of the charging transistor is maintained at a predetermined second value.