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:
Sep. 01, 2015
Filed:
Aug. 08, 2012
Hiroyuki Kojima, Gunma, JP;
Noriaki Okada, Ota, JP;
Kazuhiko Saito, Ota, JP;
Shuhei Kawai, Ota, JP;
Feng Xu, Kiryu, JP;
Hiroyuki Kojima, Gunma, JP;
Noriaki Okada, Ota, JP;
Kazuhiko Saito, Ota, JP;
Shuhei Kawai, Ota, JP;
Feng Xu, Kiryu, JP;
SEMICONDUCTOR COMPONENTS INDUSTRIES, LLC, Phoenix, AZ (US);
Abstract
In a control circuit for a light-emitting device, a reference voltage generation circuit detects a full-wave rectified voltage and generates a first voltage as well as generating a second voltage by converting the rectified voltage into a DC voltage. A voltage corresponding to a difference between the first voltage and the second voltage or a voltage corresponding to a ratio of the first voltage to the second voltage is generated as a reference voltage by a subtraction circuit or by a division circuit, respectively. As a result, a change in amplitude of the reference voltage can be suppressed when amplitude of the rectified voltage is varied due to a variation in an AC input voltage supplied from an AC power supply.