基于ANSYS/LS-DYNA板级焊点跌落分析

摘要

In order to study the influence of stress variation on the board level solder joints under different drop loads, ANSYS LS-DYNA was adopted to analyze the dynamics responses of the PCB assembly. Under different heights and different stiff targeted surface of dropping, the stress concentration area of the solder joints appeared near the interface between the BGA package and pads. The higher the height is, the bigger the stress value is. The bigger the stiffness of the targeted surface and the distribution of the stress are, the easier the solder joint failure is.%研究了不同跌落条件对板级焊点跌落时的应力变化影响.运用有限元软件ANSYS 的LS-DYNA模块对电路板组件进行建模与跌落分析,比较不同跌落高度和不同刚性跌落面下板级焊点的应力变化.结果发现:通过LS-DYNA 模块对电路板组件进行跌落仿真,能更加真实地反映出电路板组件的跌落情况.跌落后焊点的应力集中区域出现在焊点与靠近封装一侧的接触面边缘处,且跌落高度越高,焊点的最大应力值越大;接触面材料刚性越大,焊点应力分布越大,焊点越容易失效.