A new low voltage detecting method for multi-string LED BLU circuit

Author

Kang, Eun Chul ; Kwon, Duckki ; Yeon, Jae Eul ; Kim, Dong Soo ; Oh, Wonhi

Author_Institution

Fairchild Korea Semicond., Bucheon, South Korea

fYear

2009

Firstpage

1

Lastpage

6

Abstract

This paper proposes a new lowest-voltage detecting circuit for multi-channel LED backlighting units (BLUs) for LCD TVs. The proposed circuit detects the lowest voltage drop among the multi-channel LED strings with reduced number of devices. After detecting such condition the circuit provides a feedback voltage to control the output voltage of the boost converter. Therefore, it can minimize the power losses in LED driving circuit. Experimental results are presented for a 15 W boost converter driving 40 mA, 8-channel LED strings.

Keywords

driver circuits; light emitting diodes; lighting; liquid crystal displays; power convertors; television; voltage control; LCD TV; LED driving circuit; backlighting unit; boost converter; current 40 mA; low voltage detecting method; multistring LED BLU circuit; power 15 W; voltage control; Circuits; Costs; Fluorescent lamps; LED lamps; Light emitting diodes; Low voltage; Operational amplifiers; Regulators; Temperature dependence; Voltage control; Control methods for electrical systems; LCD TV; LED; LED Backlight Units;

fLanguage

English

Publisher

ieee

Conference_Titel

Power Electronics and Applications, 2009. EPE '09. 13th European Conference on

Conference_Location

Barcelona

Print_ISBN

978-1-4244-4432-8

Electronic_ISBN

978-90-75815-13-9

Type

conf

Filename

5279244