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:
May. 01, 2012
Filed:
Nov. 05, 2009
Eunchul Kang, Seoul, KR;
Duckki Kwon, Incheon, KR;
Juho Kim, Seoul, KR;
Fairchild Korea Semiconductor Ltd., Bucheon, KR;
Abstract
The present invention relates to a control device of a light emitting device that includes a plurality of LED rows formed of a plurality of LEDs sequentially connected in series. The control device includes: a plurality of switches respectively connected to the plurality of LED rows and sequentially transmitting a detection voltage of each of the plurality of LED rows, wherein the detection voltage corresponds to an output voltage applied to the plurality of LED rows; a comparator receiving the plurality of detection voltages, and generating a clock control signal according to a result of comparison with a predetermined reference; a clock signal generator generating a clock signal having a period that is changed according to the clock control signal; and a shift register that controls switching operations of the plurality of switches according to the clock signal.