Dr. Igor Kochikov received his PhD degree in computational mathematics from Moscow State University in 1985. Since 1998 with Mentor Graphics, focusing on PCB and interconnect electromagnetic modeling, providing software architecture definition and development of the fast and reliable simulation methods in signal integrity and power integrity applications. He has also been involved in computer-aided research in various fields of physics and authored several books and numerous papers in physical chemistry, optics, spectroscopy and molecular structural analysis.
In the GB/s regime, accurate modeling of insertion loss and phase delay is a precursor to successful high-speed serial link designs. We propose a causal (physically meaningful) form of the Hammerstad and Cannonball-Huray metal roughness frequency dependent complex correction factor. Compared to the widely used, non-causal form, it considerably increases the inductive component of internal metal impedance. Transmission lines simulated with a causal version demonstrate increased phase delay and characteristic impedance. By obtaining the dielectric and roughness parameters solely from manufacturers' data sheets, we validate the model through a detailed case study to test its accuracy.