Modeling of the test-fixture / Horizontal Coupling Plane interaction in system-level ESD test setups

Experimental results supported by mixed-mode simulations show how standalone ESD clamps can provide different passing levels from system-level ESD tests due to the variable impedance of the discharge current path with varied test-board size. This can lead to overdesign of the ESD protection clamp if IEC61000-4-2 current amplitudes specifications are considered, or misleading test results.