Characterization of an electrostatic discharge tester

The experimental characteristics of a commercial electrostatic discharge (ESD) tester operating in air discharge mode are reported. Specifically, the discharge current and radiated electric field intensity of a KeyTek Corp. Series 2000 ESD Tester are measured using a Tektronix 7912HB (750 MHz bandwidth) voltage transient digitizer. The following discharge waveform parameters are considered: rise times and peak values in the time domain, and amplitude and low-pass cutoff frequency in the frequency domain. The 10%-to-90% rise times increased from 1.0 kV to about 15 kV, and then decreased for the discharge current and radiated electric field intensity. The measured peak values of the radiated field (over a copper ground plate) varied from about 50 V/m to about 200 V/m. The discharge current amplitude increased with increasing spark gap voltage, as did the radiated E-field intensity. However, the cutoff frequency of the radiated E-field decreased with increasing spark gap voltage