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:
Jul. 25, 1995
Filed:
Jan. 14, 1994
Koji Arakawa, Kawagoe, JP;
Tokyo, Inc., Tokyo, JP;
Abstract
This invention provides an AC-DC converter in which the shape and the cost do not increase by a measure for a harmonic distortion in the power factor improved AC-DC converter generating little harmonic distortion. In the AC-DC converter, a control input terminal of a switching transistor of an active filter is connected to an output terminal of a flip-flop, a set input terminal of which is connected to a DC-DC converter to receive a synchronizing pulse signal therefrom. A reset input terminal of the flip-flop is connected to an output terminal of a comparator to receive an OFF-timing signal from the comparator. The comparator determines OFF-timing of the switching transistor by comparing a level voltage with an outout voltage from a saw-tooth wave generating circuit. Thereby since it is not required that an active filter has a multiplier and an an oscillating circuit, its circuit construction is simple and the AC-DC converter in small size and at low cost is realized.