本文旨在研製具有交錯式脈波寛度控制之白光發光二極體背光驅動系統，作為筆記型電腦液晶螢幕背光模組驅動器，此驅動系統使用五臂交錯式分相控制驅動電路，各臂交錯分相以驅動功率電晶體開關，由於各臂電流相位具有交錯互補功能，故具有低的直流鏈輸入均方根電流及直流鏈漣波電壓之功能。文中利用電壓回授偵測各臂白光發光二極體的短路或開路異常狀況，避免功率電晶體開關過熱燒毀。在本文驅動系統中之各臂皆具有定電流控制電路，使五臂中流經各臂白光發光二極體的電流都相等。本系統之輸入電源昇壓及穩壓採用昇壓型直流-直流功率轉換器，以非同歩控制技巧驅動功率電晶體開關，切換頻率達1MHz，可減少輸出電容器的容量。
本文以數位信號處理器(DSP, TMS320F2808)為控制核心，五臂交錯式分相脈波寬度工作控制、昇壓型直流-直流功率轉換器電壓閉迴路控制、各臂白光發光二極體開路及短路偵測，皆由軟體程式完成，可增強系統的應用功能及可靠性。本文已完成5臂7串之白光發光二極體背光模組實體製作，在鋰電池電壓模組輸入電壓範圍為12~16V，直流鏈輸出電壓為24~25V。結果顯示，直流鏈的輸入均方根電流及漣波電壓都獲得改善，各臂間電流誤差率可控制在2%以內，背光模組亮度控制可從0%~100%脈波工作寛度，以線性化改變每串電流值。二極體的短路或開路狀態偵測可自由設定各臂迴路保護機制。

This thesis presents the development of white light emitting diodes backlight with interleaved pulse-width control for note book TFT-LCD backlight driver. This driver implements five-phase interleaved time shift to control the power transistors gate signal of each phase. Each phase current is interleaved in time domain such that the input rms current and DC ripple voltage are minimized. The system uses voltage feedback to monitor WLED status. It can prevent MOSFET from being injured thermally. Each phase also has constant current control to assure that each channel current is equivalent. The boost converter uses asynchronous control to drive the power transistors. The switching frequency is 1MHz to reduce output capacitances.
In this thesis, a digital signal processor, TMS320F2808, is used as the core of five-phase interleaved pulse-width duty cycle control. The operation includes the closed-loop control of the boost converter and the detection of WLED status. The above functions are all implemented by software, and are adjustable and reliable. A 5-phase backlight module with 7 serial WLED in each phase has been implemented. The input voltage range of the battery module is from 12V to 16V. The boost converter output DC voltage is between 24V and 25V. The experimental results show that the method effectively decreases the backlight module input rms current and ripple voltage. The current inaccuracy of each phase is controlled under 2%. The brightness can be controlled linearly by pulse-width from 0% to 100%. The WLED status detection can be used to configure the protection mechanism of each phase loop.

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