Fatigue Life Prediction Model for PCB under Random Vibration

Electronic products may be subjected to vibration inevitably in the process of transport, storage, and use causing electronic equipment failure. It is necessary to estimate fatigue life of electronic equipment from the board level under random vibration. At present, the common method of estimating fatigue life for general structure is to combine S-N curve with linear fatigue damage accumulation theory. Based on this theory, a new fatigue life prediction model for PCB ( Printed Circuit Board) under random Vibration was proposed. The PCB was simplified as a single-degree-of-freedom system. Transmission rate was introduced. A relationship between frequency and damping ratio established. The fatigue life formula of the PCB under random vibration was derived. Then the influence factors of fatigue life were further analyzed using the method of finite element analysis from the aspects of material structure. Finally, taking an electronic device as an example, the life of the PCB was predicted and compared with the experimental results. The results show that the model proposed in this paper is more practical and accurate.