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. 12, 2010
Filed:
Mar. 29, 2006
Hisanori Hoshikawa, Osaka, JP;
Youichi Tamegai, Kanagawa, JP;
Isao Yamamoto, Kanagawa, JP;
Panasonic Photo & Lighting Co., Ltd., Osaka, JP;
Rohm Co., Ltd., Kyoto, JP;
Abstract
There is provided a charging device capable of improving charging efficiency and reducing power consumption, thereby increasing a battery service life. The charging device charges a main capacitor () by rectifying output voltage boosted via a self-excitation DC-DC converter, by using a diode (D). The self-excitation DC-DC converter is configured as follows. When a current value (I) flowing in a primary side (P) of an oscillation transformer (T) reaches a first predetermined value (IPK) the excitation period is terminated and energy is transmitted from the primary side (P) to the secondary side (S) of the oscillation transformer (T) so as to execute a charging period for charging the main capacitor (). The excitation period is resumed with a delay time (t) after detecting that the current value (I) flowing into the secondary side (S) of the oscillation transformer (T) is lowered than a second predetermined value (Ith).