Vibration test and simulation of printed circuit board

摘要

Automotive environment generates vibration, which can be damaging for electronic boards. Furthermore, combined temperature and vibration is a type of testing that recreates environments approximating more closely actual operating environments. High Cycle Fatigue (HCF) behaviour of the package solder joints is important for all application including vibration loading, but there is very little data in the literature on this topic. The characterization of a complex PCB was released using tension and flexure tests, to extract user input parameter for simulations. An accurate numerical model for vibration simulation was established by applying a modal analysis. Comprehensive dynamic responses of PCB, e.g., acceleration, strains and stresses, were measured and analysed in detail. Experiments were conducted to validate simulation results. The model established has excellent correlation with experimental measurement of peak displacement, output acceleration and vibration frequency. Furthermore, the influence of PCB anisotropy on the natural frequencies and mode shapes has been investigated. It was observed that, after a modal analysis, the values of the natural frequencies were not similar for isotropic and anisotropic PCBs. Then, the impact of spacing between the fixation points has been studied using different fixation configurations. The results showed that increasing spacing between the fixation points increases the values of the natural frequencies. Finally, the most constrained areas on the board were determined for several board configurations. This finding could be useful during assembling process by using the least constrained configuration.