For a high current, power type design, Or
maybe for ease of X-ray inspection. I could maybe
see the restriction.

But, for tight placement, decoupling caps, etc. there is
a huge advantage which can't be beat.

Think about memory modules with double sided BGAs.

dave


Terry Kozlyk wrote:

>Yesterday a colleague of mine at work said 2 comps on opposite sides of the
>PCB could NOT share a GND via which was nailed down to a solid plane in
>between. After thinking about it for an hour or so, I came up with my own
>several reasons. Just wanted to hear anyone elses opinions about this
>practice. I do it mainly to economize on vias taking up less space. Of
>course, the via has to be close to each comps GND pad. The comps are
>literally placed coincident to each other, for the main purpose of sharing a
>GND via.
>
> 
>
>TDK (Terry)
>
> 
>
>
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-- 
Dave Seymour, CID+
Catapult Communications Inc.
800 Perimeter Park Dr, Suite A
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