Secondary discharge - a potential risk during system level ESD testing

By means of a floating handheld electronic product this work describes the influence of secondary discharge events during system level ESD testing on the failure threshold of the involved electronic circuit. In order to increase the robustness it was necessary to determine the discharge current target levels by a dedicated test set-up which was also used to verify the success of system modifications. This was a prerequisite for identifying the sensitive pins and for increasing the ESD robustness of the system.