Are there any good resources for learning the intricacies of PCB layout when dealing with BGA packages?
I'm very familiar with layout for almost every SMT part that has leads on the edge (QFP, TSSOP, QFN, etc…) However, I have not ever had a chance to work with BGA parts because of the difficulties involved in their assembly, as the shop where I work does not have the facilities to do so.
Anyways, I've been looking into farming assembly out, and am hoping for some reference material for dealing with BGA devices.
I'm interested in both general and specifics. Escape routing, blind vias, vias in pad, SMD pads vs NSMD pads, filled and open vias, etc…
I've done a lot of sporadic reading (blogs, mainly), but am missing the bigger picture, namely how different techniques interact and a lot of basic common sense knowledge that likely comes through actual experience, even if only by proxy.
So far, I have spent some time studying any open-source project that uses BGA I can find (the BeagleBoard, Mainly) but most open source projects are not at the level of complexity that requires a BGA device, and the ones that do are rather rare.
Best Answer
If you want affordable boards, forget about blind vias, via in pad, and filled vias. This is a good presentation on BGA routing, albeit for very high-density boards, but the basic principles will be the same for less demanding layouts.
SMD pads vs NSMD pads is something you need to ask the company doing your BGA assembly about. The latter seems to be preferred. Some chip manufacturers have recommendations, as well.
If you have questions, this forum is very useful. You can also learn a lot by reading the various posts.