Finite-difference time-domain analysis of the ESD current diffusion in metallic enclosures and of the related radiated electromagnetic fields

In this paper, the problem of the electromagnetic diffusion of electrostatic discharge (ESD) currents, interfering directly on the metallic enclosures of electronic equipment, and of the electromagnetic interference (EMI) produced, is modeled and computed via a suitable finite-difference time-domain numerical approach. The levels of the radiated fields produced by standard ESD current waveforms in grounded metallic shells are evaluated, and the effects of the different arrangements of the grounding wires of the enclosure on the resulting EMI levels are discussed.