Time varying electromagnetic fields generated by electrostatic discharges

This paper presents the time domain measurements of current and electromagnetic fields generated by electrostatic discharges (ESD). Electromagnetic fields a few centimetres away from the ESD were measured in time domain using passive near field probes. The time domain signals were converted into the frequency domain by FFT, and antenna correction factors were applied. The ESD current was generated by an ESD generator. A typical ESD current of 10 A with 25 ns rise time can create a magnetic field of the order of 70 μT at a distance of 10 mm from the ESD and an electric field of the order of 6 kV/m at a distance of 30 mm from the ESD. The variation of these electromagnetic fields with distance from the discharge is also investigated