Modal analysis and dynamic responses of board level drop test

Board level solder joint reliability during drop test is a great concern to semiconductor and electronic product manufacturers. In this paper, comprehensive dynamic responses of printed circuit boards (PCBs) and solder joints, e.g., acceleration, strains, and resistance, are measured and analyzed in detail with a multi-channel real-time electrical monitoring system. Control and monitoring of dynamic responses are very important to ensure consistent test results and understand the mechanical behaviors, as they are closely related to solder joint failure mechanisms. The effects of test variables, such as drop height, number of PCB mounting screws, tightness of screws, and number of felt layers, are studied by comparing and analyzing the dynamic responses.