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:
Jan. 17, 2023
Filed:
Sep. 29, 2021
Koito Manufacturing Co., Ltd., Tokyo, JP;
Tomoyuki Ichikawa, Shizuoka, JP;
Ryosuke Matsuhana, Shizuoka, JP;
Satoshi Kikuchi, Shizuoka, JP;
Naoki Kawabata, Shizuoka, JP;
Norito Takahashi, Shizuoka, JP;
KOITO MANUFACTURING CO., LTD., Tokyo, JP;
Abstract
A lighting circuit turns on a plurality of semiconductor light sources. Multiple current sources are each coupled to a corresponding semiconductor light source. A switching converter supplies a driving voltage Vacross each of multiple series connection circuits each formed of the semiconductor light source and the current source. A converter controller employing a ripple control method turns on a switching transistor of the switching converter in response to a voltage across any one of the multiple current sources decreasing to a bottom limit voltage.