Application of measured twinax cable S-parameters for transient circuit simulations

Abstract

Practical methods of making use of measured twinax cable S-parameters for transient circuit simulations are discussed and compared. Due to extremely long delay of the cable, most available tools fail or give inaccurate simulation results if we use the measured S-Parameters directly. Careful verification is absolutely necessary for any tool. For complex tasks like the worst-case eye diagram with nonlinear I/O devices, we still need more accurate and faster methodologies. This long delay case has been accepted as a very good benchmark for testing S-parameter based SPICE modeling tools and the transient simulation tools implemented with the S-parameter convolution method.