一個低功率路徑導向簇集化電壓改變技術

Abstract

由於可攜式設備的普及化，功率較以前獲得更多的注意，並且成為除 了速度與面積外另一個超大型積體電路設計的重要考量。 在本論文中，功率最佳化技術，又稱為電壓改變技術，是我們所考慮的。 如同大家所知，功率消耗與所施電壓平方成正比，是故改變電壓可以得到 更大的功率降低率。然而，電壓改變技術有一些問題必須克服。首先，混 合電壓源會增加電路配置的困難度，並且使得繞線額外開銷快速成長。再 者，低電壓元件單元與高電壓元件單元間必須插入位準轉換器。因為位準 轉換器也會消耗能量，如何減少所需的位準轉換器便成了一項重要的課題 。最後，電路中哪些元件單元該被換成低電壓元件單元則是一個決定性的 問題。 我們的路徑導向簇集化電壓改變技術解決了上述的 問題並且在原始的簇集化電壓改變技術再提高了22％功率降低率。 Because the popularity of the portable equipments, power gets more attention than ever before, and becomes an important issue in addition to area and speed considerations in VLSI design. In this thesis, powering optimization technique, a.k.a. voltage scaling technique, is considered. As we know that power consumption is proportional to the square of the supplied voltage, then voltage scaling could get larger power reduction ratio with respect to other techniques. However, the voltage scaling technique has some problems that need to be overcome. First, mixed voltage sources will cause difficulties in circuit layout, and make routing overheads grow rapidly. Second, there are level converters needed to be inserted between low-voltage cells and high-voltage cells. Because level converters also consume power, reducing the number of level converters becomes an important issue. Finally, it is a critical problem to determine which cells in a circuit are selected to be replaced with low-voltage cells. Our path-oriented clustered voltage scaling technique solves the problems described above and add another 22% power reduction ratio over that of the original clustered voltage scaling technique.