A Method of Determining Reliability Testing Conditions for Solder Joints of Electronic Devices

A method is proposed for determining the temperature cycling test conditions for solder joints of electronic devices. First, the purpose of the temperature cycling test is clearly expressed. Next, the concept of the fatigue damage rate based on Miner's law is introduced. The fatigue damage rate is obtained from the finite element analysis of the solder joint and the fatigue strength data of the solder. In this method, the testing conditions are determined so that the damage rate during the temperature cycling test equals that in the Hield after the reliability guaranteed period. The influence of temperature and cycling frequency on the fatigue strength of the solder and the dispersion of the strength of solder joints are considered in determining the testing conditions. Finally, an example of the proposed method is shown.