Equivalent circuit modeling to calculate discharge currents for air discharges of ESD-Guns

In order to calculate discharge current waveforms for air discharges of ESD-Guns, an equivalent circuit representation is proposed by means of applying a spark resistance formula for our previously proposed circuit modeling for contact discharges. The circuit modeling consists of a voltage source derived from a spark resistance formula, the output impedance of an ESD-gun, and an injecting-point impedance of EUT or discharge target. For validation of the equivalent circuit modeling, discharge current waveforms for air discharges onto an IEC calibration target are calculated and are compared to measured waveforms. As a result, it is found that the calculated discharge current waveforms for air discharges approximately agree with measured ones.