TSOP solder joint reliability

This article reports the results on assessment of TSOP (thin small outline package) solder joint reliability. Several accelerated thermal cycling test data of various TSOPs under different cyclic temperature profiles, tested in our lab and reported by others, were analyzed in the context of the AT&T thermal fatigue database of a broad spectrum of surface mount packages-Comprehensive Surface Mount Reliability (CSMR) model. It was found that our TSOP data fitted well with the AT&T database. Four models of calculating the acceleration factor (AF) were compared for their suitability for TSOP solder joints. The failure analysis of few field returned TSOP indicated that the failure mechanism of the field returned TSOP might be different from TSOPs cycled in an accelerated thermal chamber. These observations provide explanations for discrepancy between the predicted service lives based on the accelerated thermal cycling tests and the actual service lives