本文提出一單級LED陣列驅動電路，可應用於LCD-TV的背光模組和新興的照明系統。為了降低功率損耗以及穩定性的考慮，文中使用返馳式轉換器做為電源供應器，以電流迴授模式的脈波寬度調變方式得到穩定輸出電壓，輸出級的部分採用電壓控制電流源，以運算放大器迴授取得一可調光的定電流輸出來驅動LED。使得每一LED電流相同，減少個別LED之間輝度之差異。其特點在於電壓輸入範圍大、輸出電壓穩定及輸出電流不受負載變動影響。最後由暫態響應分析驗證當LED負載變動，無論形成斷路或短路時，都可由迴授網路在短的時間內回復。

In the thesis, a single stage driver of LED arrays is addressed. It can be applied in lighting system and back-light for LCD-TV. In order to reduce the power consumption and the consideration of stability, flyback converter that can maintain the output voltage constant by using fixed frequency current-mode PWM modulation is used to be power supply. A transconductance amplifier with voltage control is employed so that the output current is almost constant. It ensures a constant current to drive LEDs without disturbance due to the forward voltage and voltage source. The features of this work are the wide input range, stable output voltage and dimming with reference voltage. Last, by the analysis of the transient response, it can be found that the output voltage can recover within a short time while the loads are changing.

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