*I don't think IPC formally addresses this in their guidelines,*
*but here's the scoop in a nutshell:*
**
*Your fabricator wants to remove them because it saves*
*drill bit wear by not having to drill through so many*
*non-functional pads.*
**
*IPC says (informally?) along with many reliability experts*
*to leave them in, forming a more robust "rivet-like" structure,*
*less barrel cracking, etc.*
**
*I leave them in.*
**
*hope that helps,*
*Jack*


On 6/20/07, Matthew Lamkin <[log in to unmask]> wrote:
>
> Apologies if this has already been posted, I just came across it trying to
> find
> some info on removing via pads on internal layers (can anyone point to any
> articles for why/why not to do this?)
>
> The first hit on a Google search for "suppressing vias internal layers
> pcb" was this:
>
> http://www.patentstorm.us/patents/7016198.html
>
> eh?
>
> Matthew
>
>
>
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