Multiple Edge Responses for Fast and Accurate System Simulations

High-speed input/output (I/O) link performance is limited by random noise as well as signal integrity issues such as dispersion, reflections, and crosstalk. Hence, accurate prediction of system performance including these random and deterministic noise is crucial in high-speed link design. This paper presents a novel, fast, and accurate method to simulate the time-domain system response. The presented method calculates the system response using multiple edge responses (MER) based on linear superposition. Being able to take into account system nonlinearity more accurately, the presented method significantly improves simulation accuracy compared with the other published fast simulation techniques based on either single bit response (SBR) or double edge responses (DER), while at the same time maintaining equivalent numerical efficiency. Furthermore, peak distortion analysis, which is commonly used to find the worst-case data pattern based on SBR, is extended for DER and MER using dynamic programming. A multiphase worst-case data pattern approach is also introduced in this paper in order to determine the worst-case system performance under both timing and voltage consideration.