近幾年，由於發光二極體各項應用起飛，包括大型看板、車用發光二極體與背光源使用逐年提高。在面板應用上，背光源通常需要大量的發光二極體來提供光源，因此若能有效率佳且負載能力好之驅動電路則將可以降低系統成本。所以設計出一個能量密度高、轉換效率佳、重量輕體積小的升壓型DC-DC電源轉換器，成為可討論的議題，也成為發光二極體在連續工作下的可靠度、發光效率及受用的關鍵。
　　本論文是具電流模式控制升壓穩壓器之四通道調光高匹配電流LED驅動電路，其輸入電壓為12V，而輸出電壓為35V。為了可以達到所要求的輸出電壓，其回授控制電路以脈波寬度調變之方式來實現，並擁有根據發光二極體順向電壓改變的迴授機制，使此電路能夠提供更高的可靠度，來提供發光二極體所需的電壓及電流使用。另外考量到各通道發光二極體所需的電流匹配度，藉由本篇論文提出的高精度晶片佈局技術幫助下，各通道間的LED電流可達到極為精確的匹配，對製程、溫度、電壓(PVT)變異擁有高容忍度。本論文採用數位脈衝寬度調變(Digital Pulse Width Modulation，DPWM)方式，利用人眼視覺暫留的現象以完成定電流LED亮度調整，避免色彩偏移(Color Shift)問題，且具有線性調光功能。

　　In recent years, the commercial possibilities of the LED are increasing gradually since the applications of light-emitting diode are more and more prevalent in large scanning boards, vehicle-used light-emitting systems and backlight-used display systems.In the applications of the LCD panel, the backlight source usually needs large amount of light-emitting diode to provide enough brightness.Therefore, if the driver circuit has high efficiency and good driving capability, the cost of the LED system can be reduced. It is possible to design a high energy density, good conversion efficiency, light weight and small size of the boost DC-DC power converters, can be the issue of discussion, but also a light-emitting diode reliability in continuous operation, the luminous efficiency and the key to using good enough.
　　This thesis proposes a Current Mode Boost Converter with Four-Channels Highly Precise Current Matching LED Driver for Dimming . The input voltage is 12V and the output voltage is 35V. In order to achieve a desired output voltage, the boost voltage regulator used a pulse width modulation (PWM) and a reference tracking circuit according to the variation of forward voltage of LEDs. The advantage of the proposed method is to offer high reliability to the LED voltage and current use.Moreover considering the accurately matched LED currents for multi-channel Through the help of highly matched layout scheme, the accurately matched LED currents for multi-channel are achieved with high tolerance to process, temperature and voltage (PVT) variations. The color shift problem of LED brightness can be avoided by using digital pulse width modulation (DPWM) control, and the DPWM technique has capability of linear dimming.

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