Numerical modeling of electrostatic discharge generators

The discharge current and the transient fields of an electrostatic discharge (ESD) generator in the contact mode are numerically simulated using the finite-difference time-domain method. At first the static field is established. Then the conductivity of the relay contact is changed, which initiates the discharge process. The simulated data are used to study the effect of design choices on the current and fields. They are compared to measured field and current data using a multidecade broadband field and current sensors. The model allows accurate prediction of the fields and currents of ESD generators, thus it can be used to evaluate different design choices.