Building accurate Spice models for multi-Gbps interconnect in computer systems

In this paper, we established an efficient methodology to build accurate Spice models for multi-Gbps interconnects in computer systems. The transmission lines are modeled with frequency dependent RLGC matrices, with surface roughness included. The vertical discontinuities are modeled with full-wave EM solver, and converted to equivalent Spice models through rational function approximation. VNA measurements were performed on a typical multi-Gbps interconnect that includes package, socket, PCB and via, etc. Calculated S parameters with the Spice models correlate very well to measurement data from DC up to 14 GHz or higher.