Full-Wave Simulation of System-Level Disruption during Secondary ESD Events in a Smartphone

To demonstrate the electromagnetic full-wave simulation of a secondary electrostatic discharge (ESD), an ESD generator is modeled in three dimensions (3D) and in contact mode discharging to a non-grounded, metallic ear-mesh of a smartphone. The nonlinear Rompe-Weizel SPICE model computes the arc resistance of the secondary discharge between ungrounded metal and a grounded enclosure. The SPICE model is solved using a circuit simulator, and the 3-D model is solved using the transmission-line matrix time-domain numerical method. Transient cosimulation is a new technique that is used to solve both circuit and 3-D models at the same time. The simulation predicts the coupling from ESD to a victim trace in the smartphone. Measurements performed at several stages validate the simulation results. Using this novel methodology, the user can simulate the secondary discharge in products to predict ESD damage and disruption on a system level.