Hi gang! I have been looking for some data and am not having any great success so I thought I would ask TechNet! I am looking for solder joint integrity data for BGAs and CSPs where you have a two sided board and the BGAs or CSPs are "mirrored" (aka side one has a BGA exactly opposite of a BGA on side 2). I have found publications discussing the impact of mirrored BGAs due to rework but I am looking more specifically for the influence of having a mirrored configuration (or even a partially mirrored configuration) on the solder joint integrity in thermal cycle conditions. There seems to be some industry tribal knowledge that having a mirrored BGA/CSP configuration causes a degradation in solder joint integrity but I am not finding supporting data in the industry literature. If you know of any published papers/reports, please send me the citation and I can run down the papers. TIA Dave Hillman Rockwell Collins [log in to unmask] ______________________________________________________________________ This email has been scanned by the Symantec Email Security.cloud service. For more information please contact helpdesk at x2960 or [log in to unmask] ______________________________________________________________________