eispice is a clone of the Berkley Spice 3 Simulation Engine with a Python based front-end. It contains a subset of standard spice device models and a set of unique models that are targeted towards PCB level Signal Integrity
MMTL (Multilayer Multiconductor Transmission
Line) is a 2-D and 2.5-D electromagnetic
modeling tool suite. It generates transmission
parameters and SPICE models from
descriptions of electronics interconnect
dimensions and materials properties.