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:
Nov. 02, 2010
Filed:
Sep. 28, 2007
Takuya Ishii, Osaka, JP;
Mikio Motomori, Osaka, JP;
Junichi Morita, Osaka, JP;
Takashi Ryu, Kyoyo, JP;
Masaaki Koto, Osaka, JP;
Makoto Ishimaru, Osaka, JP;
Kazuhito Kimura, Kyoyo, JP;
Satoshi Wada, Osaka, JP;
Takuya Ishii, Osaka, JP;
Mikio Motomori, Osaka, JP;
Junichi Morita, Osaka, JP;
Takashi Ryu, Kyoyo, JP;
Masaaki Koto, Osaka, JP;
Makoto Ishimaru, Osaka, JP;
Kazuhito Kimura, Kyoyo, JP;
Satoshi Wada, Osaka, JP;
Panasonic Corporation, Osaka, JP;
Abstract
The present invention provides a current-mode control step-up converter capable of reducing the minimum duty ratio to a sufficiently small value and facilitating the setting of the maximum duty ratio. The step-up converter comprises a current detectorfor generating a current detection signal Vc corresponding to the current of a rectifier; an error amplifierfor generating an error signal Ve corresponding to an output DC voltage Vo; and a control circuitfor turning ON/OFF the main switchon the basis of the current detection signal Vc and the error signal Ve. The control circuitcomprises a comparatorand a timer circuit. With this configuration, the ON time of the main switchis set at a predetermined value, and the valley value of an inductor current changing in a triangular waveform is controlled. Hence, the OFF time of the main switch is adjusted to stabilize the output. Since the ON time of the main switchcan be set as desired, the minimum duty ratio can be reduced to zero or a sufficiently small value.