Embedded tutorial: Fundamentals of macromodeling for signal integrity analysis

Computer aided design tools are an integral part of the design flow of modern electronic systems. However, lack of physical consistency of the models that are used in the simulation and optimization cycle can cause the design tools to slow down unpredictably or even fail. This tutorial provides a comprehensive analysis of this important topic, with emphasis on relevant properties of the macromodel and associated data such as causality, stability and passivity and their interdependency. These properties are crucial for the transient simulation of high-speed modules. Several design scenarios will be examined to show the effects of consistency violations on real design tasks, while outlining suitable best-practice rules to avoid them. Finally, an overview of the best numerical techniques for checking and enforcing physical consistency during measurement, modeling and simulation tasks will be presented.