An electrical-level superposed-edge approach to statistical serial link simulation

Abstract

Brute-force simulation approaches to estimating serial-link bit-error rates (BERs) become computationally intractable for the case when BERs are low and the interconnect electrical response is slow enough to generate intersymbol interference that spans dozens of bit periods. Electrical-level statistical simulation approaches based on superposing pulse responses were developed to address this problem, but such pulse-based methods have difficulty analyzing jitter and rise/fall asymmetry. In this paper we present a superposing-edge approach for statistical simulation, as edge-based methods handle rise/fall asymmetry and jitter in straightforward way. We also resolve a key problem in using edge-based approaches, that edges are always correlated, by deriving an efficient inductive approach for propagating the edge correlations. Examples are presented demonstrating the edge-based method's accuracy and effectiveness in analyzing combinations of uniform, Gaussian, and periodic distributed random jitter.