LED Driver With Self-Adaptive Drive Voltage

This paper presents an LED driver circuit consisting of multiple linear current regulators and a voltage preregulator with adaptive output voltage. In the proposed driver, the output voltage of the preregulator is always self-adjusted so that the voltage across the linear current regulator of the LED string with the highest voltage drop is kept at the minimum value that is required to maintain the desired string current. Because the linear current regulators in this driver operate with the minimum voltages, the driver efficiency is maximized. The performance of the proposed driver was experimentally verified on a four-string LED setup with eight white LEDs in each string. The measured efficiency improvement of the linear current regulators was approximately 15% compared to the corresponding implementation with a constant preregulator voltage.

[1]  S. Sze Semiconductor Devices: Physics and Technology , 1985 .

[2]  Javier Uceda,et al.  The discontinuous conduction mode Sepic and Cuk power factor preregulators: analysis and design , 1997, IEEE Trans. Ind. Electron..

[3]  Jingquan Chen,et al.  Analysis and design of SEPIC converter in boundary conduction mode for universal-line power factor correction applications , 2001, 2001 IEEE 32nd Annual Power Electronics Specialists Conference (IEEE Cat. No.01CH37230).

[4]  Yingqi Zhang,et al.  A new soft switching technique for buck, boost and buck-boost converters , 2002 .

[5]  Masao Nakagawa,et al.  Fundamental analysis for visible-light communication system using LED lights , 2004, IEEE Transactions on Consumer Electronics.

[6]  N. Narendran,et al.  Life of LED-based white light sources , 2005, Journal of Display Technology.

[7]  J.Y. Tsao,et al.  Solid-state lighting: lamps, chips and materials for tomorrow , 2005, (CLEO). Conference on Lasers and Electro-Optics, 2005..

[8]  S. Buso,et al.  Analysis of a High-Power-Factor Electronic Ballast for High Brightness Light Emitting Diodes , 2005, 2005 IEEE 36th Power Electronics Specialists Conference.

[9]  한주원 A high efficiency led driver , 2006 .

[10]  Cheng-Ju Wu,et al.  A Simplified LED Converter Design and Implement , 2006, JCIS.

[11]  Huang-Jen Chiu,et al.  LED Backlight Driving System for Large-Scale LCD Panels , 2007, IEEE Transactions on Industrial Electronics.

[12]  Heinz van der Broeck,et al.  Power driver topologies and control schemes for LEDs , 2007, APEC 07 - Twenty-Second Annual IEEE Applied Power Electronics Conference and Exposition.

[13]  Giovanni Carraro Solving high-voltage off-line HB-LED constantcurrent contro-circuit issues , 2007, APEC 07 - Twenty-Second Annual IEEE Applied Power Electronics Conference and Exposition.

[14]  D. Weng,et al.  Quasi-Active Power Factor Correction Circuit for HB LED Driver , 2007, APEC 07 - Twenty-Second Annual IEEE Applied Power Electronics Conference and Exposition.

[15]  Pan TianFu,et al.  An Improved Single-Stage Flyback PFC Converter for High-Luminance Lighting LED Lamps , 2007, 2007 8th International Conference on Electronic Measurement and Instruments.

[16]  Regan Zane,et al.  Digital Architecture for Driving Large LED Arrays with Dynamic Bus Voltage Regulation and Phase Shifted PWM , 2007, APEC 07 - Twenty-Second Annual IEEE Applied Power Electronics Conference and Exposition.

[17]  Tsai-Fu Wu,et al.  Sequential Color LED Backlight Driving System for LCD Panels , 2007, IEEE Transactions on Power Electronics.

[18]  S. Yuvarajan,et al.  Quasi-Active Power Factor Correction Circuit for HB LED Driver , 2007, IEEE Transactions on Power Electronics.

[19]  Huang-Jen Chiu,et al.  An improved single-stage Flyback PFC converter for high-luminance lighting LED lamps , 2008 .

[20]  S.-Y. Tseng,et al.  LED backlight power system with auto-tuning regulation voltage for LCD panels , 2008, 2008 Twenty-Third Annual IEEE Applied Power Electronics Conference and Exposition.

[21]  M.M. Hernando,et al.  A very simple control strategy for power factor correctors driving high-brightness light-emitting diodes , 2008, 2008 Twenty-Third Annual IEEE Applied Power Electronics Conference and Exposition.

[22]  Wei-Hsu Chang,et al.  A Digital boost converter to drive white LEDs , 2008, 2008 Twenty-Third Annual IEEE Applied Power Electronics Conference and Exposition.