負回授預先增強電壓產生的液晶螢幕驅動電路

Abstract

液晶螢幕驅動電路在整個液晶螢幕中是一個相當重要的元件，負責把所接收到的畫素資料顯示在螢幕上。在液晶螢幕中，較高的影格速率可以為液晶螢幕的帶來較好的影像畫質。在本論文中提出了一個以「負回授」的方式來尋找最佳的預先增強電壓波形，可以使得液晶螢幕隨時都可以找到一個脈波寬度，使得不同的畫素都可以有最快的上升時間。所設計的負回授預先增強電壓產生電路，在畫素電壓是二點三五伏的畫素電壓時，與未使用預先增強電壓產生電路比較有三點四微秒的上升時間改善，在控制電路和可調的單位脈衝寬度也比先前的文獻有大幅度的改善。 本晶片採用0.35微米CMOS製程製作，負回授預先增強電壓產生電路的晶片面積為756 μm×646 μm。在五伏的供應電壓之下，核心電路的功率消耗少於7毫瓦。可將本論文所提出的設計概念應用在真正的液晶螢幕驅動電路中，來達到較好的影像品質。

LCD driver is an important component in the LCD. It receives the pixel data and shows it on the monitor. In the LCD monitor, higher frame rate can have better image quality. In this thesis, a feedback method for finding the best pre-emphasis voltage waveform is proposed. It can makes the LCD monitor find a best pulse width to have the highest rise time of each pixel at anytime. The LCD driver with feedback pre-emphasis voltage generation circuit has 3.4μs rise time improvement compared with the LCD driver without it when the pixel voltage is 2.35V. The control circuit and tunable pulse width also have large improvement than previous work. The chip is fabricated in 0.35μm CMOS technology. The chip area of the pre-emphasis voltage generation circuit is 756 um×646 um. The core circuit consumes less than 7mW at 5V supply voltage. It can realize the design concept designed in this thesis to a real LCD driver to have better image quality.