Hi Bob -  As precious as real estate tends to be under BGA's for circuit
layout and heat removal, the non plated hole is probably more than many of
us can afford.  This is something that could well be accomplished on a
development board to support the solder profiling operations, then never
used again.  Most of the newer convection furnaces are a bit easier to deal
with and less tempermental than their predecessors, making the process more
stable.  Development boards could also be used to support R&R equipment
profiling.

Regards - Kelly



-----Original Message-----
From: Bob Walker <[log in to unmask]>
To: [log in to unmask] <[log in to unmask]>
Date: Wednesday, August 25, 1999 9:21 PM
Subject: [DC] PCB designs using BGAs


>Hi All,
>
>I'd like to know how many designers provide an unplated hole under each BGA
>component in a design, so that a thermocouple can be placed to monitor
>temperature. I'm thinking of doing this in all of my designs to help make
it
>easy to create a temperature profile on a new design. Do you use more than
>one hole or is one sufficient?
>
>Regards,
>
>Bob Walker
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