Routability checking for general area routing problems

This paper presents a scheme for checking the routability of nets for use in general area routing problems (GARPs). The scheme is based on the extended Pascal´s triangle method which was previously proposed as a routability measure for GARPs. It also uses the counting method of Pascal´s triangle for determining the number of potential routes of each net. However, instead of performing a comprehensive analysis for each net, the new scheme considers a subset of grids within the net´s bounding box for fast routability determination. This technique detects if the nets will be potentially routable in the presence of arbitrary obstacles including possible limitations on the number of vias/bends. Experimental results of the proposed technique are presented