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:
Oct. 20, 2015
Filed:
Jul. 28, 2014
Applicant:
Panasonic Corporation, Osaka, JP;
Inventors:
Assignee:
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
H05B 37/02 (2006.01); H05B 33/08 (2006.01);
U.S. Cl.
CPC ...
H05B 33/0818 (2013.01);
Abstract
A lighting device includes a DC/DC converter (step-down chopper circuit) and a control circuit that includes a correction circuit. The correction circuit corrects the timing at which a switching element included in the DC/DC convertor is turned OFF based on a voltage value across a solid-state light-emitting element (LED unit). The correction is made such that an average value of a current flowing through an inductor included in the DC/DC converter is within a predetermined range regardless of a voltage value across the solid-state light-emitting element.