Article

An Exact Jumper-Insertion Algorithm for Antenna Violation Avoidance/Fixing Considering Routing Obstacles

Dept. of Electr. Eng., Nat. Taiwan Univ., Taipei
IEEE Transactions on Computer-Aided Design of Integrated Circuits and Systems (Impact Factor: 1.2). 05/2007; DOI: 10.1109/TCAD.2007.892338
Source: IEEE Xplore

ABSTRACT We study in this paper the problem of jumper insertion on general routing (Steiner/spanning) trees with obstacles for antenna avoidance/fixing at the routing and/or postlayout stages. We formulate the jumper insertion for antenna avoidance/fixing as a tree-cutting problem and present the first optimal algorithm for the general tree-cutting problem. We show that the tree-cutting problem exhibits the properties of optimal substructures and greedy choices. With these properties, we present an O((V+D)lgD)-time optimal jumper-insertion algorithm that uses the least number of jumpers to avoid/fix the antenna violations on a Steiner/spanning tree with V vertices and D obstacles. Experimental results show the superior effectiveness and efficiency of our algorithm

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