利用低溫多晶矽薄膜電晶體整合源極驅動電路於顯示面板上之可行性研究

Abstract

本論文提出一種能以全數位訊號來驅動的新型源極驅動電路架構及一種實現源極驅動電路陣列(SoA，Source Driver on Array)技術的方法。SoA電路利用脈衝寬度調變(PWM)電路、資料電壓設定電路(Data Voltage Setting Circuit)來取代數位類比轉換器與緩衝器，藉此簡化源極驅動電路。新型的源極驅動電路少了類比電路的部分，因此較容易使用薄膜電晶體將源極驅動電路直接製作於玻璃基板上。進一步的，我們將對源極驅動電路陣列技術的可行性進行研究。結果發現，如果我們想要利用薄膜電晶體來完成源極驅動電路陣列技術，在佈局面積及功率消耗方面將是一大的阻礙。有利的是，全數位訊號驅動的觀念可以使源極驅動電路發展成數位界面的架構。我們利用外部的源極驅動電路來產生數位脈寬訊號，進而設定畫素電壓。此方法避免了佈局面積及功率消耗的議題。因此，從佈局面積及功率消耗的觀點來看，發展數位界面的觀念較源極驅動電路陣列技術來的可行與實際。

In this thesis, we proposed a new kind of source driver with fully digital driving and a new approach to implement source driver on array (SoA). For the SoA circuit, the digital/analogue converters (DACs) and buffers are replaced with pulse width modulation (PWM) circuit and data voltage setting circuit to simplify the source driver. Thus, the signal converting part in the conventional source driver can be omitted and is much more easily to be built with thin film transistors on the glass. Further, the feasibility of integrating source driver on array will be studied in the practical way. The layout area and power are found to the obstacles if we want to use the current thin-film transistor (TFT) technology to implement SoA. However, the fully digital driving concept can be still be applied to develop the configuration of digital interface. We can use the external source driver to produce the digital pulse width signal to set the pixel voltage. This method avoids issue of layout area and power. Hence, the concept of digital interface is much more practical and feasible to reduce the layout area and power of data driving instead of SoA.