Abstract
An ESD (electrostatic discharge) testing is specified in the IEC 61000-4-2, in which the detailed waveform of the discharge current injected by an ESD-gun is prescribed. However, due to lack of understanding of the discharge process, it is difficult to confirm whether or not such the IEC current waveform be injected onto actual equipment. We thus previously proposed an equivalent circuit model for the ESD-gun based on its geometrical structure, and showed decisive factors for the discharge current. In this study, in order to confirm the feasibility of the above equivalent circuit model, we measured with a 6-GHz wide-band digital oscilloscope the discharge current through an SMA connector and the resultant magnetic near-field for the contact discharge of an ESD-gun. As a result, we found that both the measured waveforms approximately agree with those calculated from our equivalent circuit model. We then measured with respect to charge voltages the magnetic near-fields for the contact discharge of the ESD-gun to the ground, which showed that the measured waveform around the first peak fairly agrees with the calculated one. Furthermore, we also found that the magnetic field peak increases with increasing the charge voltage, whose dependence can be predicted from our equivalent model.
