[snip] > At 03:53 PM 11/29/2001 -0600, Jeff Stout wrote: > >1. Can I use a hole pair that goes through the prepreg, but > >does not go through the core material above or below that > >level? I just don't see how it can be manufactured. > > No. At least not to my knowledge. My understanding of the process is that > basically you can only use blind vias on cores. You may not connect cores > to one another except with full through-hole vias. > Exception: If you have 2 internal cores you can prepreg these together and > then drill through them... plate to connect these cores together, and then > prepreg more cores to the outside of that unit, through-hole drill the > whole thing and plate again, etc, etc, etc. >
So if you want to connect two layers across a layer of prepreg, your stuck with having holes on the outside of the two cores surounding the prepreg. Well t'aint that shitty. So in a PCB, with a stack up like: T --C-- 1 --P-- 2 --C-- 3 --P-- 4 --C-- B It's only possible to manufacturer: T -> 1 T -> 3 T -> B 2 -> 3 2 -> B 4 -> B Without having some extra "through holes" somewhere, of course. I think I'm beginning to understand this. Jeff Stout [snip] * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * To post a message: mailto:[EMAIL PROTECTED] * * To leave this list visit: * http://www.techservinc.com/protelusers/leave.html * * Contact the list manager: * mailto:[EMAIL PROTECTED] * * Forum Guidelines Rules: * http://www.techservinc.com/protelusers/forumrules.html * * Browse or Search previous postings: * http://www.mail-archive.com/[email protected] * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
