Contents I. Introduction
Quasi static models have been used to model electromagnetic propagation along interconnects since the late 19th century when Oliver Heaviside invented distortionless transmission lines and proposed extending the telegraphs range with lumped coils [1]. While interconnect circuit models are inherently approximate, they are useful when the frequencies are low and dimensions are small [2]. For interconnect analysis this means the cross-section of a wire, its neighbors and their high frequency return path is small relative to the wavelengths of interest and the lines and planes are discretized sufficiently short. PATSextends this approach into the 21st century for package signal integrity analysis. PATSextracts circuit models and uses a fixed-time step circuit simulator to create time domain scattering models [3] which are then used in an internal transmission line simulator (FastLine) [4] for system level signal analysis.
