[PEDA] First BGA design with blind-buried vias.

[Brian Guralnick]

Ok, I'm still using P99SE.

    I need to upgrade an existing project with the main IC being a 240 QFP, 
going to an Altera 484 pin, 1mm fineline BGA, however, there are some parts 
under the chip.

    My PCB is only 6 layers.  I've never done blind/buried vias before in 
protel.  How should I configure protel to handle the blind-buried vias under 
the BGA pads.  Am I attempting something that shouldn't be done?  Can some 
BGA pads just be pads with no holes at all without upsetting the mounting? 
Is there any good reason to switch to microvias?


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Brian G.