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:
Mar. 23, 2010
Filed:
Oct. 02, 2007
Takae Shimada, Hitachi, JP;
Fumikazu Takahashi, Hitachi, JP;
Hiroyuki Shoji, Hitachi, JP;
Yoshihide Takahashi, Odawara, JP;
Wataru Mochizuki, Ninomiya, JP;
Takae Shimada, Hitachi, JP;
Fumikazu Takahashi, Hitachi, JP;
Hiroyuki Shoji, Hitachi, JP;
Yoshihide Takahashi, Odawara, JP;
Wataru Mochizuki, Ninomiya, JP;
Hitachi Computer Peripherals Co., Ltd., Kanagawa, JP;
Abstract
To provide a power supply apparatus having high control resolution of an output power. A PWM signal generating circuit includes: a non-inverting element, and an inverting element; and further includes a counterfor performing count operation in response to rising of a clock signal, a counterfor performing count operation in response to falling of the clock signal, comparison circuits, and a multiplexer. These circuit elements are controlled by PWM control means. As another circuit element, the PWM signal generating circuit includes a logical sum element. The PWM signal generating circuit serves to arbitrarily change both period and logic 'H' time of a PWM signal to be outputted at a time interval which is one half of the clock period. Thus, there is provided a power supply apparatus in which resolution of a PWM signal has been improved within a broad duty range, and fine control of an output power has been performed within a broad output power range.