Investigating the solder mask defects impact on leakage current on PCB under condensing humidity conditions

Abstract

This paper focuses on conducting a thorough investigation into the solder mask defects and their influence on the leakage current development in PCB under operating conditions. A practical commercial PCBA has been used as a reference to construct a realistic numerical model, integrating the solder mask layer through COMSOL software. Comprehensive investigations cover scenarios with and without pinholes, conducting precise electrochemical reaction simulations under critical electrical conditions for validation against experimental data. The outcomes notably reveal how pinholes level up leakage current (LC) and reshape its paths. To validate the proposed method, experiments under real operating conditions and humidity were conducted. The comparison between the simulation and experiments demonstrated the effectiveness of the numerical model.