Werner Almesberger wrote: > ?lvaro Lopes wrote: >> Not good for RF lines - vias introduce a lot of reflection. > > So you'd keep RF on the surface ? And RF signals crossing a can > boundary get a hole in the can ? I now see that this seems to be > what has been done with GPS.
Yes, that's exactly it. Same reason to avoid 90 degree direction changes in RF lines - reflection. >> BOTTOM: components + routing >> L7: ground (less strict) >> L6: routing + ground >> L5: ground (strict) ?? >> L4: (power routing ?) >> L3: ground (strict) ?? >> L2: power >> TOP: components, routing > > So you'd start with 8 layers and then see if two of them end up > bring avoidable ? No, I think we should start with a 6 layer. Unless someone disagrees. I was just stating what I think is current FR PCB layer structure. > >> Current design has many. Not sure we can avoid buried vias at all. > > The fewer layers we have, the less difference there is between a > buried and a blind via ;-)) True, true :) Álvaro _______________________________________________ gta02-core mailing list [email protected] https://lists.openmoko.org/mailman/listinfo/gta02-core
