由於液晶面版的寄生電容和寄生電組的存在，導致液晶驅動電路中的功率大部分都消耗在面版的交流功率上(AC power)。要降低面版交流功率，可由降低改變電壓(Swing Voltage)部分著手。傳統的方法雖然可以有效降低改變電壓，但是先前的方法需要外部大電容輔助。增加外部電容將會導致I/O pad增加，此外傳統方法的電路繞線也比較複雜。本篇論文利用液晶面版的寄生電阻和寄生電容，提出一個多相位電荷平均方法來降低改變電壓，降低驅動電路的功率損耗。電路中不同的群組大小(Group Size)，將會影響省電的效率和電路複雜度。較大的群組可以得到較高的省電效率，但是額外付出的代價是使用較複雜的控制電路和開關。在我們提出的方法中，可以有相當多的電路組合可以達到低功率設計的要求，我們利用程式找出最佳化的架構。並且透過步驟壓縮，將執行改變電壓步驟減少，亦即是減少操作時間。另外基於實際的考量，有限的開關距離可以降低電路繞線的複雜度，並且降低找尋最佳電路組合的時間複雜度。得到幾組最佳化的組合後，將這些組合實現成電路，並且帶入四種不同的測試數據做比對，模擬結果顯示，當群組大小為八的時候，與不做任何省電裝置比較，可以得到23-68%的省電功率。與前人的研究作比較可以得到10-18%％的省電功率，但是不用外加大電容，且電路較為簡單。

A novel multi-phase charge-sharing technique is proposed for the dot inversion method to reduce AC power consumption of the TFT-LCD column driver without requiring any external capacitor for charge conservation. The Searching Algorithm discovers near-optimal configurations. After the exhaustive search, Phase Compression is also applied to reduce the time of charge conservation. For realistic consideration, the switching distance is limited to reduce the complexity of Searching Algorithm and decrease switch routing between column lines. Simple and easy-to-control circuitry is applied in the proposed method, and the power saving efficiency depends on number of charge phases. Increasing the number of charge phases, the saving power efficiency is also raised. Excluding power dissipation of switches, the power saving efficiency is up to 75% theoretically with infinite phases. For previous work, the maximum power saving efficient is 50% without external capacitor. The HSPICE simulation results including power dissipation of all switches show that the proposed method with seven charge phases (eight-column lines as one group) decreases the power consumption of 23%-68% and 10%-18%, respectively, compared with original circuit (without any low-power scheme) and previous low-power charge-recycling works.

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