Interconnection delays in hierarchical timing simulation

A simple and efficient method has been developed for computing interconnection delays in an event-driven hierarchical simulator, when multiple driving sources are present. The theory is based on T.M. Lin and C.A. Mead´s algorithm (see IEEE Trans. Comput.-Aided Design, vol. CAD-5, p.188-197, 1986) for computing delays in general RC networks by converting them to trees using node splitting. However, their algorithm requires iteration to solve the resulting linear system of equations. The present technique requires no iteration and yet gives the same results. The accuracy improves as technology is scaled down and when interconnection delays dominate