Combined circuit/full-wave simulations for electromagnetic immunity studies based on an extended S-parameter formulation

This paper describes an extended S-parameter formulation for electronic subcomponents (printed circuit boards, integrated circuits,...) which includes both the regular S-parameter description between the circuit ports of the subcomponent as well as an extra column/row characterizing the coupling between the circuit ports and outgoing/incoming plane waves. The advantage of this extended S-parameter model is that it can be easily integrated into regular circuit simulators and connected to complex linear or non-linear circuitry. This allows to study both Electro-Magnetic Emission and Immunity phenomena in full detail. In this paper, the extended S-parameter model is specifically applied to the study of Electro-Magnetic Immunity problems. In a first example, the influence of an incoming plane wave on the eye diagram of a differential pair is studied. In a second example, the extended S-parameter formulation is combined with a behavioral model of an integrated circuit in order to characterize the radiated immunity of the integrated circuit.