Download ESDEMC_TN001 ESD Target Adapter Line Calibration Method (PDF )
1. Calibration Objective
The objective of this report is to calibrate the ESD target adapter line and check its performance and compare the results to the requirements of the IEC 61000-4-2 standard.
Requirements from IEC 61000-4-2 standard:
The 50 ohm conical adapter line connects the 50 ohm cable to the input of the ESD target. Geometrically, it smoothly expands from the diameter of the 50 ohm coaxial cable to the diameter of ESD target. If the target is made such that the impedance calculated from the diameter ratio d/D not being equal to 50, the target adapter line shall be made such that the outer diameter of its inner conductor equals the diameter of the inner electrode of the current target. The impedance is calculated considering the dielectric constant of the material that fills the conical adapter line (typically air).
The target adapter line shall show an impedance of 50 ohm +/-2% from DC to 4 GHz. The reflection coefficient of two target adapter lines face-to-face mounted shall be better than 30 dB up to 1 GHz and better than 20 dB up to 4 GHz while the insertion loss shall be less than 0.3 dB in the same configuration.
2. Measurement Setup and Results:
In the test, two identical ESD target adapter lines are mounted face to face and connected to a calibrated network analyzer.
The measure results, S11 and S22 values, show the reflection coefficient of the ESD Target adapter line, which according to the standard the value should be better than 30 dB up to 1 GHz and better than 20 dB up to 4 GHz, the S21 or S12 values show the insertion loss of the shall be less than 0.3 dB. The results below are the examples passed the Requirements from IEC 61000-4-2 standard: