具有數位亮度調整之白光發光二極體驅動器晶片設計

Design of the White LED Driving Chip with Digital Brightness Adjustment

游東明(Dong-Ming Yu)

指導教授 ： 宋國明

國立臺北科技大學/機電學院/電機工程系所/碩士(2006年)

摘要

本篇論文描述一個內建數位亮度調整功能的白光發光二極體驅動器晶片，利用限流脈波頻率調變(Current-limited Pulse Frequency Modulation)控制架構，完成升壓式直流對直流轉換器，再者利用脈波寬度調變(Pulse Width Modulation)的方式完成亮度調整功能。當輸入電壓3V時輸出電壓可達23V，輸出電流可達40mA以上，因此輸出端可提供兩條電流迴路(每條迴路20mA)，其中一條迴路作為LCD基礎背光源，另一條迴路作為亮度調整的光源，每條迴路均可以驅動6顆白光LED。
本論文的直流對直流升壓轉換器控制晶片實現上採用TSMC 0.35μm，2P4M互補金氧半混合信號製程，面積為1.39mm×1.53mm。當輸入電壓4V、輸出電壓23V以及輸出電流40mA時，系統轉換效率可達87% 。

關鍵字

限流脈波頻率調變 ； 脈波寬度調變 ； 電流幫浦轉換器 ； 白光發光二極體

並列摘要

This paper will describe the white LED driver with digital brightness adjustment on chip. By using the control structure of current-limited pulse frequency modulation, we can implement the Boost DC-to-DC switching converter. Furthermore, the brightness turning will be completed with the pulse width modulation technique. When the input voltage is 3V, the system output voltage can be boosted up to 23V and the output current value is greater than 40mA. Thus the output port can supply two loops of current (each one flow through 20mA), one is for the base source light of the LCD, the other for the source light of brightness adjustment. Each loop can drive six white LEDs.
The proposed chip is designed and implemented with the TSMC 0.35um 2P4M CMOS process. The simulation results show that the chip area, the power efficiency, the output voltage and the output current are 1.39mm×1.53mm, 87%, 23V, 40mA, respectively.

並列關鍵字

Current-limited Pulse Frequency Modulation ； Pulse Width Modulation ； Charge Pump converter ； White LED

參考文獻

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