Baking is more like damage control than a preventative measure. Baking is used when life goes wrong, as it so often does. Storing MSD is not the issue. Not storing MSD is. Central services are a thing of the past. Distributed processing is were people want be.
We have been talking about solutions to storing MSD on SMTnet since the beginning of time. Why sonny, I recall a thread back in �99 when Chris G. was talking about converting a frig to a N2 cabinet. Now those were the days, eh?
Storing MSD: Storing devices in a humidity-free cabinet until seconds before the component is required would be real nice. Goody, everyone gets his or her own cabinet. Finally, we�ve been saying that for years.
Scale of the problem * Moisture sensitivity is not a NEW problem. Years ago, we baked all of our boards prior to mass soldering. We still schedule a bake of multiwire boards prior to paste print. * Some tantalum capacitors take on moisture and we solder them after board cleaning. * 98 per cent of our MSD don�t cause us to miss a beat. * Accounting for exposure time is not a trivial problem. Firms sell bar code software to help manage this issue.
For us, �poor planning� drives to the requirement for MSD baking. Just about everyone stirs that fine kettle of soup [Marseillais fine bouillabaisse, I think].
General observations are: * �In my view this is rework.� => Could be. It does indicate imperfection. * �The component was manufactured and shipped correctly and should not need baking in order to use it.� => Sounds good. Most classes of MSD packaging have a self-life. Lots of times it�s expired before it comes in-house. * �The component was manufactured and shipped correctly and should not need baking in order to use it.� => Sounds good. Try as we might, most MSD package quantities does not match-up with product lot sizes.
reply »