A high-efficient WLED driver using light-balanced-controlled techniques with current-locked loops

作者：Chen Jiann Jong^*; Hwang Bo Han; Guo Yao Ren; Hwang Yuh Shyan; Yu Cheng Chieh

来源：Analog Integrated Circuits and Signal Processing, 2012, 72(2): 363-373.

DOI：10.1007/s10470-012-9886-8

• Current sensing circuit
• LED driver
• Buck converter

The proposed high-efficient WLED driver using light-balanced-controlled techniques with current-locked loops is presented in this paper. This LED driver has 500: 1 current sensing ratio and 1 kHz PWM dimming frequency. The maximum output current of the buck converter is 100 mA and the output voltage range is from 3.5 to 4.8 V with a 20 and 18 mu H off-chip capacitor and inductor, respectively. The maximum efficiency of the proposed LED driver is 87.8 % and the current difference between each LED string is 1.33 %. And it is fabricated with TSMC 0.35 mu m 2P4 M CMOS processes. The chip area is 1.52 mm x 1.36 mm.

• 出版日期2012-8