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http://dx.doi.org/10.7236/JIIBC.2015.15.1.245

Design of a PWM-Controlled Driving Device for Backlightsof LED Systems  

Um, Kee-Hong (School of IT, Hansei University)
Publication Information
The Journal of the Institute of Internet, Broadcasting and Communication / v.15, no.1, 2015 , pp. 245-251 More about this Journal
Abstract
In this paper, we present a design of PWM-controlled driving device for backlights in LED systems. The system can control either the brightness of the entire screen of backlights of LCD driven by LED or illumination or contrast of each partial segment of the entire screen. The PWM-controlled driving device includes the shift register that shifts the series data according to the clock signal prior to the generation of parallel data. It is also is comprised of a number of registers, a number of counters, a number of comparators, and a number of synchronizing gates (producing the PWM-controlled signals). The proposed device for backlights in LED systems can generate the PWM-controlled signal with a high degree of resolution without the increase of clock frequency. It also contains the PWM-controlled circuit that disperses and restrains the quantized noise.
Keywords
Light emitting diode; Backlight; Cold cathode fluorescent lamp; PWM; TFT-LCD;
Citations & Related Records
Times Cited By KSCI : 1  (Citation Analysis)
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