近年來發光二極體的應用極為廣泛，包括液晶顯示器、LED照明、面板顯示器背光源等，通過使用LED作為背光，可獲得更高的效率、較廣的色域、調光能力高、壽命長和環保節能等。而一般白光LED正向電壓為3到3.6 V，串聯十顆LED則電壓需要30到36 V，已超過一般常見可攜式的電池所能提供的電壓，因此需要直流-直流升壓型轉換器將電源電壓升高以驅動LED串列。
本論文提出一應用於LED驅動電路之切換式升壓型轉換器，應用端使用矩陣式數位脈衝寬度調變LED驅動電路以控制四通道LED串調光，並選用擁有快速暫態響應之自適式導通時間控制架構作為設計，以增強響應速度。
本次設計晶片實現於TSMC 0.25 μm CMOS 高壓製程，其輸入電壓操作於5 V，輸出電壓則可藉由內建之帶差參考電路將輸出穩定在35 V，其前模擬結果顯示，最大輸出電壓之漣波大小約為2.3%，負載電流範圍(20 mA~120 mA)，其中在負載電流為70 mA時，可達最高能量轉換效率91.75%。

In recent years, light-emitting diode (LED) has been widely applied to various circuits, such as liquid-crystal display, lighting, etc. A better power efficiency, wider color gamut, better dimming capability, longer lifetime and more environmental friendly solution can be obtained by using LEDs as the backlight. The typical forward voltage of white LED is about 3 V to 3.6 V. Therefore, the voltage of ten LEDs in series will be around 30 V to 36V, which is usually greater than the voltage provided by batteries in common of portable applications. Hence, boost DC-DC converter is needed to boost the supply voltage to a higher output voltage to drive series of LEDs.
In this thesis, a boost converter for DPWM LED driver is proposed for four-channel LED dimming control. The adaptive on-time control stratagem is employed to enhance the response time by fast transient response.
The chip is realized in a TSMC 0.25μm 1P3M CMOS 60V high voltage process. The operational input voltage is 5 V and the output voltage is stabilized at 35 V. With pre-simulations, the output ripple is around 2.3% under load current range of 20 mA~120 mA. The peak power conversion efficiency is 91.75% at 70 mA load current.

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