Journal of Electrical Engineering and Technology

The Korean Institute of Electrical Engineers (대한전기학회)
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High Efficiency Multi-Channel LED Driver IC with Low Current-Balance Error Using Current-Mode Current Regulator

  • Yoon, Seong-Jin (Dept. of Electrical and Electronic Engineering, Kangwon National University) ;
  • Cho, Je-Kwang (Raontech. Inc.) ;
  • Hwang, In-Chul (Dept. of Electrical and Electronic Engineering, Kangwon National University)
  • Received : 2016.11.17
  • Accepted : 2017.05.16
  • Published : 2017.07.01
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Abstract

This paper presents a multi-channel light-emitting diode (LED) driver IC with a current-mode current regulator. The proposed current regulator replaces resistors for current sensing with a sequentially controlled single current sensor and a single regulation loop for sensing and regulating all LED channel currents. This minimizes the current mismatch among the LED channels and increases voltage headroom or, equivalently, power efficiency. The proposed LED driver IC was fabricated in a $0.35-{\mu}m$ BCD 60-V high voltage process, and the chip area is $1.06mm^2$. The measured maximum power efficiency is 93.4 % from a 12-V input, and the inter-channel current error is smaller than as low as ${\pm}1.3%$ in overall operating region.

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References

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