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A Novel Time Based Current Compensator for LED Back Light Modules
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A Novel Time Based Current Compensator for LED Back Light Modules

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Abstract:

The paper proposes a novel time based brightness compensation circuit for LED back light modules. The brightness of LED decays while running under constant current driven condition. We have designed a suitable controller to compensate the driving currents to maintain the brightness. The compensation data were calculated from the relative luminous efficiency – time curve provided by the LED manufacturer and were stored in the microprocessor. -The embedded system used the running time of the LED in the back light module as an independent variable for tuning the driving current. The experiment results showed that the brightness of different operating times’ LED arrays can be held almost the same as the new ones.

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Periodical:

Key Engineering Materials (Volumes 364-366)

Pages:

377-382

DOI:

https://doi.org/10.4028/www.scientific.net/KEM.364-366.377

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Online since:

December 2007

Authors:

Yi Hua Fan, Cheng Ju Wu, Chen Chao Fan, Kuo Wei Chih, Lun De Liao

Keywords:

LED Back Light Module, Time Based Current Compensator

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© 2008 Trans Tech Publications Ltd. All Rights Reserved

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