隨著製程不斷的進步，漏電流功率已成為功率消耗的主因之一，為了解決這個問題，電源關斷(power gating)結構已被廣泛使用在當今的超大型積體電路(VLSI)中，在此結構的設計議題中，以瞬間輸入浪湧電流(Rush current)，開機時間(wake up time)，電源開關開啟時間(sequence time)為最重要的議題。因此在此篇論文中，我們提出一個包含菊花鏈(daisy chain)以及分散式魚骨(foshbone)結構的混和式電源開關繞線結構，先利用菊花鏈結構對整體電源網路作緩慢的充電，利用此結構的特性降低瞬間輸入浪湧電流，且利用本論文所提出的充放電模型去估量所需的最小菊花鍊深度，當電源網路已充到一定準位後，再利用魚骨結構做快速的開啟，因電源網路已充到一定準位，此時利用魚骨結構開啟不會引起大量的瞬間輸入浪湧電流，且可讓整體電源開關開啟時間大量降低。我們的結構已實現在奇景公司(Himax Technologies Inc.)所提供的設計上，根據PrimeRail的測量，我們的結構的確不僅可以降低瞬間輸入浪湧電流，且可以大量減少電源開關開啟時間。

As technology advances, leakage power increases dramatically in modern VLSI designs. To reduce leakage power, power-gating technology has been widely applied to circuit designs. Rush current and sequence time of the circuits are determined by the turn-on speed of power switches. To consider this problem, this paper proposes a hybrid routing structure, which includes a daisy chain and fishbone, to connect power switches. First, it builds a daisy chain to slowly charge voltage to a desired value in order to reduce rush current. According to the model and the equations proposed by this paper, proper number of power switches in a daisy chain which can satisfy the design constraint can be determined quickly. To further reduce sequence time, fishbone is applied to connect the remaining power switches. Experimental results show that our methodology builds designs which have smaller rush current than those using daisy chain only. More importantly, our designs still have small sequence time in real designs provided by Himax Technologies Inc..

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