A wire length estimation technique utilizing neighborhood density equations

Abstract

This paper presents a new wire length estimation technique for row-based design. Noting that the local topological structure of the network is often reflected in the local structure of the placement, we present a technique of topological analysis of the network, in which the local structure of the network is characterized by a growing sequence of multilevel neighborhoods. By assuming a pointwise independent branching process, we derive equations for the probability density of multilevel neighborhoods. The wire length distribution is found by solving these equations. For thirteen industrial circuits tested, this technique gives an average of 15.1% estimation accuracy.