The Transactions of The Korean Institute of Electrical Engineers (전기학회논문지)

The Korean Institute of Electrical Engineers (대한전기학회)
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Design of an Active Current Regulator for LED Driver IC

LED 구동 IC를 위한 능동 전류 조절기의 설계

  • 윤성진 (강원대 공대 전기전자공학과) ;
  • 오택준 (강원대 공대 전기전자공학과) ;
  • 조아라 (강원대 공대 전기전자공학과) ;
  • 기석립 (강원대 공대 전기전자공학과) ;
  • 황인철 (강원대 전기전자공학과)
  • Received : 2011.12.14
  • Accepted : 2012.03.08
  • Published : 2012.04.01
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Abstract

This paper presents an active current regulator for LED driver IC. The proposed driver circuit is consists of DC-DC converter for supplying constant DC voltage to LED, active current regulator for compensating channel-to-channel current error from LED strings and feedback circuit for controlling duty ratio of the converter. The proposed active current regulator senses current of LED channels by equalizing both $V_{DS}$ and $V_{GS}$ at LED current control transistor. Because the proposed circuit directly measures the LED channel current without a sensing resistor and regulates all channel with same regulation loop, the power consumption and the current error are much small compared with previous works. The measured maximum efficiency of overall LED driver IC is approximately 94% and current error of LED channel-to-channel is under ${\pm}1.3%$. The proposed LED driver IC is fabricated Dongbu 0.35um BCD process.

Keywords

References

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  1. Simple LED driver with Constant Current Control vol.3, pp.4, 2014, https://doi.org/10.11142/jicems.2014.3.4.422