TRANSIENT SIMULATION OF LOSSY INTERCONNECTS BASED ON THE RECURSIVE CONVOLUTION FORMULATION

A new approach for transient simulation of lossy interconnects terminated in arbitrary nonlinear elements is presented. The approach is based on convolution simulation. By making use of the Pade approximations of each line's characteristics or each multiconductor lines' modal functions, we derive a recursive convolution formulation, which greatly reduces the computation used to perform convolutions. The approach can handle frequency-varying effects, such as skin effects, and general coupling situations. In this paper, we analyze the errors introduced by Pade approximations and develop a scheme to determine the necessary order for an approximation. We have incorporated the proposed approach to the stepwise equivalent conductance timing simulator (SWEC) [1], [2] for digital CMOS circuits. The comparisons with SPICE3.e [7] indicate that SWEC, which gives accurate results, can be one to two order-of-magnitudes faster.