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:
Feb. 28, 2012
Filed:
Jun. 20, 2008
Noboru Akiyama, Hitachinaka, JP;
Takayuki Hashimoto, Tokai, JP;
Takashi Hirao, Hitachi, JP;
Koji Tateno, Takasaki, JP;
Noboru Akiyama, Hitachinaka, JP;
Takayuki Hashimoto, Tokai, JP;
Takashi Hirao, Hitachi, JP;
Koji Tateno, Takasaki, JP;
Renesas Electronics Corporation, Kawasaki-shi, JP;
Abstract
A power-supply control IC is included in a switching power supply which drives to turn on and off a semiconductor switching device connected to a DC power supply in series to supply a predetermined constant voltage to an external load, and is a semiconductor device including a semiconductor circuit which controls on and off of the semiconductor switching device. When a current flowing through the load is abruptly increased to cause an error voltage to exceed a predetermined first threshold voltage after the end of a PWM on-pulse generated in synchronization with a switching cycle, a second PWM on-pulse is generated within the same switching cycle. Furthermore, in a plurality of switching cycles after the switching cycle in which the second PWM on-pulse is generated, the first threshold voltage for comparison with the error voltage is switched to a second threshold voltage higher than the first threshold voltage.