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:
Jun. 17, 2014
Filed:
Jul. 20, 2010
Keisuke Takahashi, Yokohama, JP;
Keisuke Takahashi, Yokohama, JP;
Ricoh Company, Ltd., Tokyo, JP;
Abstract
A charging device to charge a secondary battery that includes a DC/DC circuit to generate a charging current supplied to the secondary battery, an impedance measurement circuit to measure an impedance of the secondary battery, a first control circuit to output a duty-cycle decrease signal in accordance with the measured impedance, a charging-current monitor circuit to detect the charging current outputted from the DC/DC circuit when the duty cycle of the pulses generated by the DC/DC circuit is decreased by the duty-cycle decrease signal, and, a second control circuit to compare the charging current detected by the charging-current monitor circuit and a charging-current threshold and to output to the DC/DC circuit a frequency change signal that increases a switching operation frequency in the DC/DC circuit.