本文提出一種LED矩陣驅動電路，用於新興的照明系統和背光模組，利用功率曲線，提出最短距離之最佳工作電壓和電流，以決定最佳LED元件之排列組合；驅動LED採定電流源，使每一LED電流相同，減少整體輝度之差異。電流源之架構採電壓控制式電流源，其優點為定電流輸出而方便於系統電壓回授控制，使LED不受其順向電壓VF本身波動值以及電源電壓變動的影響。文中除了電路架構中各元件值之設計考量，本研究僅用三條線連結LED背光板完成一設計實例，實驗與量測和理論預測結果相當接近。

A LED matrix driving circuit for use in lighting and back-lighting statues is proposed. Minimum distance from power dissipation curve is adopted to determine optimal operating voltage and current, which give an optimal combination of LEDs. A transconductance amplifier is employed as a constant current source with voltage control. It ensures a constant current to drive LEDs without disturbance due to the forward voltage VF and voltage source. In addition to design consideration in components evaluation, a design example with easy three-wire connection for LED arrangement is explored. The experimental result is close to the theoretical predictions.

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