Patent ID: 6182272
Filing Date: 2001-01-30
Classification: G06F

Abstract:
A method for assigning routing layers to connection segments in integrated circuit design, said method comprising:an obtaining step of obtaining a routing description of a net that includes plural connection segments and plural vertices, each of the plural vertices being a vertex;a generating step of generating a tree-shaped routing graph from the routing description by selecting one of the plural vertices to be a root and forming edges corresponding to the connection segments such that each vertex other than the root has only one edge leading to it from a next higher hierarchical level;a determining step of determining penalty values for plural different potential routing layer assignment combinations by traversing the tree-shaped routing graph in a bottom-up fashion, wherein each potential routing layer assignment combination represents one possible combination of assignments of at least a subset of the edges to specific routing layers; andan assigning step of assigning routing layers to the plural connection segments based on the penalty values determined in said determining step.