Werner Almesberger wrote: > ?lvaro Lopes wrote: >> How are we to use those layers ? Which will be mostly ground, vcc, and >> routing ? > > I was thinking of something like this (assuming six layers): > > - TOP (LCM side): components, local routing, and test pads > - L1: power (routing if necessary) > - L2: ground (less strict) > - L3: routing > - L4: ground (strict) > - BOTTOM (battery side): components and local routing > > That way, we can "sandwich" EMI-sensitive traces between ground planes > in layer 3.
Not good for RF lines - vias introduce a lot of reflection. But might be good for other signals. > But ... I've never designed a multilayer board myself, let alone one > with RF subsystems, so my ideas may be totally wrong. > >> Shall we use OM approach ? > > Hmm, what would that be ? >From a quick inspection: BOTTOM: components + routing L7: ground (less strict) L6: routing + ground L5: ground (strict) ?? L4: (power routing ?) L3: ground (strict) ?? L2: power TOP: components, routing > >> I also think we can do it with a 6-layer, as long as we can use >> buried and blind vias. > > Blind vias should be no problem. I would try to avoid buried vias > if we can. Not only because they may make the board harder to > manufacture, but also because they effectively hide a trace from > measurements. Current design has many. Not sure we can avoid buried vias at all. Álvaro _______________________________________________ gta02-core mailing list [email protected] https://lists.openmoko.org/mailman/listinfo/gta02-core
