本論文旨在研製三原色LED混光驅動控制電路，其特點在於加入光學回授補償與數位式調光機制，可補償因LED發光強度衰減時造成的混光配比錯誤。運用三原色LED能使液晶顯示器色彩重現範圍大於NTSC 100%，文中首先分析RGB LED各種電氣與光學特性，並應用色彩工程學之加法混色系統，以亮度色度計BM-7A測量其三刺激值，計算混合白光配比，再藉由積分球量測系統驗證單顆RGB LED確實能混合白光後，研製背光驅動電路並製作RGB LED背光模組。由於RGB LED三種顏色各自的導通電壓不同，需要三組電壓源，本論文選用多輸出返馳式電能轉換器供應RGB LED三組電壓，並搭配常見的定電流電路，使LED操作在定電流特性下。但是RGB LED會受到時間及其他因素影響，光輸出會降低使得原來混光配比不正確，故加入光感測器進行光學回授補償，以微處理器為主要控制系統，將混合白光配比、光感測器發光強度與電壓關係特性整理成一資料庫，進行回授補償，達成穩定白光輸出之效果。

The purpose of this paper is to develop a mixed RGB LEDs driving circuit. First, to measures the electric and optical characteristic of RGB LEDs. And based on additive color mixing of color engineering to calculate mixing ratio, in further, utilize the integrating sphere to verify whether RGB three in one LED is mixed white light. Second, implement RGB LEDs backlight driving circuit for LCD Panel. Because RGB LEDs have different operation voltage, need multi-output flyback converter to supply three voltage for RGB LEDs, collocating constant current circuit to achieve accurate current control among RGB LEDs strings. Finally, LED is a semiconductor device so many factors affect its light-emitting characteristics. Photo sensor can be used for optical compensation and peripheral-interface -controller (PIC) is used as a controller. The feedback controller has to maintain the preset flux form each LED to roughly maintain white point.

[1] M. R. Secades, A. J. Calleja, J. Ribas, E. L. Corominas, J. M. Alonso, J. Cardesin, and J. G. Garcia, “Evaluation of a low-cost permanent emergency lighting system based on high-efficiency LEDs,” IEEE Trans. Ind. Electron ., vol. 41, no. 5, pp. 1386-1390, 2005.
[2] A. Bhattacharya, B. Lehman, C. A. DiMarzio, A. Shteynberg, and H. Rodriguez, “Effects of parametric uncertainty in designing a high -brightness LED light system,” in Proc. IEEE APEC’08, 2008, pp. 544 -550.
[3] I. H. Oh, “An analysis of current accuracies in peak and hysteretic current controlled power LED drivers,” in Proc. IEEE APEC’08, 2008, pp. 572-577.
[4] M. Nishikawa, Y. Ishizuka, H. Matsuo, and K. Shigematsu, “An LED drive circuit with constant-output-current control and constant-luminance control,” in Proc. IEEE INTLEC’06, 2006, pp. 1-6.
[5] H. V. D. Broeckl, G. Sauerlander, and M. Wendt, “Power driver topologies and control schemes for LEDs,” in Proc. IEEE APEC’07, 2007, pp. 1319-1325.
[6] C. Y. Hsieh and K. H. Chen, “Boost DC-DC converter with charge-recycling (CR) and fast reference tracking (FRT) techniques for high-efficiency and low-cost LED driver,” in Proc. IEEE ESSCIRC’08, 2008, pp. 358-361.
[7] Y. Hu and M. M. Jovanovic, “A novel LED driver with adaptive drive voltage,” in Proc. IEEE APEC’08, 2008, pp. 565-571.
[8] M. Doshi and R. Zane, “Digital architecture for driving large LED arrays with dynamic bus voltage regulation and phase shifted PWM,” in Proc. IEEE APEC’07, 2007, pp. 287-293.
[9] 曾偉菁，發光二極體發光特性與其驅動電路之研究，國立成功大學電機工程學系碩士論文，2006年。
[10] Z. Ye, F. Greenfeld, and Z. Liang, “Design considerations of a high power factor SEPIC converter for high brightness white LED lighting applications,” in Proc. IEEE PESC’08, 2008, pp. 2657-2663.
[11] K. Zhou, J. G. Zhang, S. Yuvarajan, and D. F. Weng, “Quasi-active power factor correction circuit for HB LED driver,” IEEE Trans. Power Electron., vol. 23, no. 2, pp. 1410-1415, 2008.
[12] C. C. Chen, C. Y. Wu, and T. F. Wu, “Fast transition current-type burst-mode dimming control for the LED back-light driving system of LCD TV,” in Proc. IEEE PESC’06, 2006, pp. 1-7.
[13] 莊佳璋，具數位調光控制之掃瞄式LED背光驅動電路，國立成功大學電機工程學系碩士論文，2008年。
[14] C. L Chiu and K. H Chen, “A high accuracy current-balanced control technique for LED backlight,” in Proc. IEEE PESC’08, 2008, pp. 4202 -4206.
[15] P. Y. Chen, Y. H. Liu, and J. H. Teng, “RGB LED backlight driving system with area control,” in Proc. IEEE ICSET’08, 2008, pp. 765-768.
[16] 林宏森，以RGB發光二極體為LCD背光源之光學回授補償，國立中央大學光電科學研究所碩士論文，2005年。
[17] 吳宗樺，三原色發光二極體背光源之驅動電路，國立中山大學電機工程學系碩士論文，2007年。
[18] 許煜偉，三原色LED之白光感測與調和，國立成功大學電機工程學系碩士論文，2009年。
[19] H. J. Chiu and S. J. Cheng, “LED backlight driving system for large-scale LCD panels,” IEEE Trans. Ind. Electron., vol. 54, no. 5, pp. 2751-2760, 2007.
[20] Y. K. Lo, K. H. Wu, K. J. Pai, and H. J. Chiu, “Design and implementation of RGB LED drivers for LCD backlight modules,” IEEE Trans. Ind. Electron., vol. 56, no. 12, pp. 4862-4871, 2009.
[21] 韓斌，液晶顯示器中的發光二極體，科學發展435期，第 28-35頁2009年。
[22] F. Bernitz, O. Schallmoser, and W. Sowa, “Advanced electronic driver for power LEDs with integrated colour management,” in Proc. IEEE ISA’06, 2006, pp. 2604-2607.
[23] S. Muthu, F. Schuurmans, and M. Pashley, “Red, green, and blue LEDs for white light illumination,” IEEE J. Sel. Topics in Quantum Electron., vol. 8, no. 2, pp. 333-338, 2002.
[24] S. Muthu, F. Schuurmans, and M. Pashley, “Red, green, and blue LEDs based white light generation: Issues and Control,” in Proc. IEEE IAS’02, 2002, pp. 327-333.
[25] S. Muthu, F. Schuurmans, and M. Pashley, “Red, green, and blue LED-based white light source: Implementation challenges and control design,” in Proc. IEEE IAS’03, 2003, pp. 515-522.
[26] S. Y. Lee, J. W. Kwon, H. S. Kim, M. S. Choi, and K. S. Byun, “New design and application of high efficiency LED driving system for RGB -LED backlight in LCD display,” in Proc. IEEE PESC’06, 2006, pp. 1-5.
[27] P. Grootes, N. Kaito, R. F. M. Hendriks, C. A. Schrama, E. Stassar, and D. Claessens, “LED light source for backlighting with integrated electronics,” U.S. Patent 0046485, 2007.
[28] S. Muthu and C. Chang, “RGB LED based light driver using microprocessor controlled AC distributed power system,” U.S. Patent 6,510,995, 2003.
[29] S. Muthu, F. J. Schuurmans, C. Chang, and J. Gaines, “LED-based white -light backlighting for electronic displays,” U.S. Patent 6,753,661, 2004.
[30] I. H. Oh, “A single-stage power converter for a large screen LCD back-lighting,” in Proc. IEEE APEC’06, 2006, pp. 1058-1063.
[31] OSRAM Inc., “LED display backlighting-monitor applications using 6-lead MULTILED,” Application Note, 2005.
[32] Lumileds Inc., “Luxeon DCC for LCD Backlighting,” Application Brief AB27, 2005.
[33] H. Sugiura, S. Kagawa, H. Kaneko, M. Ozawa, H. Tanizoe, T. Kimura, and H. Ueno, “Wide color gamut displays using LED backlight-signal processing circuits, color calibration system and multi-primaries”, in Proc. IEEE ICIP’05, 2005, pp. 9-12.
[34] C. C. Chen, C. Y. Wu, P. C. Lu, Y. M. Chen, and T. F. Wu, “Sequential color LED back-light driving system for LCD panels,” in Proc. IEEE IPEMC’06, 2006, pp. 1-5.
[35] Y. F. Chen, C. C. Chen, and K. H. Chen, “Mixed color sequential tech- nique for reducing color breakup and motion blur effects,” J. Display Technol., vol. 3, pp. 377-385. 2007.
[36] C. Y. Wu, T. F. Wu, J. R. Tsai, Y. M. Chen, and C. C. Chen, “Multi- string LED backlight driving system for LCD panels with color sequential display and area control,” IEEE Trans. Ind. Electron., vol. 55, pp. 3791 -3800, 2008.
[37] M. H. Huang, Y. C. Tsai, C. Y. Hsieh, and K. H. Chen, “An energy recycling (ER) technique for field color sequential LCD backlight driving,” in Proc. IEEE CICC’09, 2009, pp. 523-526.
[38] 周志敏、周紀海、紀愛華，LED驅動電路設計與應用，五南圖書出版股份有限公司，2008年
[39] 谷善平編著，白中和譯，新光電元件應用技術，建興文化事業有限公司，2003年。
[40] 鈴木佐喜雄編著，鄭明哲編譯，光電裝置應用技術，文笙書局股份有限公司，1991年。
[41] 大田登編著，陳鴻興/陳君彥譯，基礎色彩再現工程，全華科技圖書股份有限公司，2003年。
[42] PO-FT5050FCZ-011 Data Sheet, Power Opto Inc., 2006.
[43] S9032-02 Data Sheet, Hamamatsu Inc., 2003.
[44] C9303-04 Data Sheet, Hamamatsu Inc., 2007.
[45] Q. Chen, F. C. Lee, and M. M. Jovanovic, “Analysis and design of weighted voltage-mode control for a multiple-output forward converter,” in Proc. IEEE APEC’93, 1993, pp. 449-455.
[46] S. Winder, Power Supplies for LED Driving, Elsevier Publishers, 2008. ISBN 978-0-7506-8341-8