電源網路規劃 (Powerplanning)一直是實體設計中一個非常重要的議題。隨著製程進入奈米時代，功率消耗呈現劇烈地成長，因此多重電壓設計 (Multiple-supply voltage design) 常被使用來降低動態功率的降低，這使得電源網路的設計複雜度變得越來越高。目前工業界的做法大多數是透過經驗豐富的工程師利用手動的方式去完成電源網路規劃，這樣的方式不僅會拉長整體實體設計流程需要花費的時間，而且也常常會浪費不必要的繞線資源。雖然過去學術界有許多關於這方面的研究被提出，但是它們使用的方式多半是去調整電源網路金屬線的粗細，以滿足電壓下降的限制，此方式和工業界實際的做法不同。因此，為了滿足工業界的需求，我們在本論文提出一個可應用在多重電壓設計的電源網路規劃方法。為了節省電源網路的面積，我們提出了一個兩階段的設計流程來調整電源網格的密度，最後，我們還將產生的電源網路載回實際的工具中。實驗的結果顯示，我們所自動產生的電源網路不僅僅可以符合電壓下降的限制，而且比使用規律網格方式產生的電源網路使用更少的金屬線。

Powerplanning is an important issue in physical design flow for a long time. As process technology advances, dynamic power grows dramatically. Hence, a multiple-supply voltage (MSV) design is widely used to handle this problem, which makes Powerplanning become more difficult. In industries, powerplanning is usually made by handcraft and takes a lot of time, which increases Time-to-Market. Besides, it may waste unnecessary routing resource. Although there exist several works discussing powerplanning, most of these researches usually adjust metal widths to handle this problem, which is not adopted by industries. In order to satisfy requirements in industries, this thesis proposes a powerplanning methodology which can be applied in multiple-supply voltage designs. To reduce routing resource, a two-stage approach is proposed to adjust density of power meshes. Besides, powerplanning results are imported back to commercial tools. The experimental results demonstrate that power networks generated by our approach require less routing resource than those use regular power mesh.

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