Prognostic health monitoring method for printed circuit boards subjected to random cyclic loads

For random dynamic loads such as cyclic shock and vibration of semiconductor modules, a method using field load assessment and fatigue life estimation is proposed in order to improve the reliability of electronic products. The evolutionary spectrum method is introduced for random dynamic load modeling. The statistical distribution of structural responses such as the deformation and strain of solder joints and printed circuit boards can be predicted by Monte Carlo simulations based on the finite element method and random dynamic load modeling. A feasibility study of the failure probability estimation method is conducted for application to a printed circuit board on which a flip-chip ball grid array (BGA) package is mounted using BGA solder joints. The proposed method is found to be useful for prognostic health monitoring of solder joint failure.