PWB Internal Short – Example C
This slide presents a failure analysis case study of a printed wiring board (PWB) that developed an internal short during burn-in testing. The cross-sectional SEM images highlight localized laminated damage, which was likely caused when a warped board was forcibly mounted flat, inducing internal mechanical stress. Comparison with an undamaged region confirms the localized nature of the failure. Additionally, the use of an unusual blind via construction appears to have exacerbated the issue, contributing to the internal short.