薄膜電晶體液晶顯示器全數位驅動法之驗證

Verification of Fully Digital Driving Method for TFT LCD

何宗軒(Tsung-Hsuan Ho)

指導教授 ： 戴亞翔

國立交通大學/電機學院/電機學院電子與光電學程/碩士(2018年)

摘要

本論文驗證之前所提出以Ramp-Stop概念來操作的新型全數位介面源極驅動電路的可能問題，以確認其可行性。全數位介面源極驅動電路使用脈衝寬度調變(PWM)電路、電位轉換器(Level Shifter) 、以及做在玻璃上的資料開關(Data Switch) ，以Ramp-Stop的概念來取代傳統源極驅動電路中的數位/類比轉換器與緩衝器，藉此使源極驅動電路全數位化。新型的全數位源極驅動電路少了類比電路的部分，因此在功率消耗上以及佈局面積上的表現會優於傳統類比介面電路，全數位驅動電路也降低了設計難度及縮短了設計的時程。另外我們也進一步的提出各種有可能發生的問題如：功率消耗問題、寄生電容造成的延遲問題及開關元件的均勻性問題，並針對這些問題進行模擬及實作研究，結果發現，這些問題都不會對顯示品質有所影響。總之，全數位介面源極驅動電路不但可在佈局面積及功率消耗上取得優勢，在充電電壓控制上也比傳統類比電路來的容易。我們認為全數位界面源極驅動電路在未來是很有潛力可以完全取代舊有的類比驅動電路。

關鍵字

全數位驅動資料IC ； 全數位驅動法

並列摘要

In this thesis, the possible issues of the previously proposed fully digital interface data driver are verified to prove its validity. The circuit uses the concept of ramp-stop by manipulating the pulse width of the control signal to catch the moment to stop the ramp voltage. In new method, we use pulse width modulation (PWM) circuit, level shifter and data switch to replace the conventional digital-to-analog converter (DAC) and buffer to fully digitalize and simplify the data driver. Due to reduce analogue circuit, the fully digital data driver can offer benefits include less power consumption, less layout area and shortened design schedule. In the meantime, we have studied the possible issues of power consumption, device non-uniformity, and parasitic capacitance. The results proved the fully digital driving method has advantage of less layout area, less power consumption and flexible timing control can fully replace conventional analogue method. Therefore we believed the fully digital driving method is prospectively expected to substitute for the conventional analogue driving method in the future.

並列關鍵字

Fully digital driving data driver ； Fully digital source driver

參考文獻

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