Measurement of Transient Magnetic Field caused by ESD between Spherical Electrodes using a Shielded Loop Probe and Current Estimation of EM Radiation Model

Abstract

Transient magnetic field caused by micro-gap ESD was measured to examine the discharge current of a dipole radiation model. The magnetic field measured by a shielded loop probe, a conversion factor from an output voltage of the probe to the magnetic field strength was derived as a probe correction factor (magnetic-field antenna factor) obtained by the three-antenna method. The magnetic field strength calculated by the conversion factor considering the frequency characteristic of probe correction factor using a process of FFT and IFFT. As a result, the peak value of magnetic near field strength was about 500 A/m - 700 A/m in discharge voltage of 600 V.