Domain characterization of transmission line models and analyses

Electronic system design requires noise and delay analyses of lossy, low-loss, frequency dependent, and coupled transmission lines, along with lumped parasitic elements. Numerous models and techniques have been developed for simulating these interconnect circuits, however, no single method represents the optimal approach for all transmission line problems. Accuracy and efficiency considerations would suggest the use of different models and analyses for the various types of interconnects. Such an approach to simulating transmission lines requires a measure of goodness for selecting the appropriate model and analysis in terms of the circuit parameters. Toward this goal, this paper presents an efficient methodology for characterizing transmission line models into solution domains. This provides an efficient technique for automatically selecting the type of interconnect model and analysis. Specifically, for a specified acceptable modeling error, analysis domains are established for automatic model selection between the classical method of characteristics, a lumped modeling approach and the state-based convolution technique within a simulation and analysis tool. In general, however, this approach can be applied to any combination of models and analyses, if a measure of accuracy and efficiency can be established.