On Sat, Sep 10, 2005 at 04:17:48PM -0400, Timothy Miller wrote:
>
> Coplanarity is a concern, and one thing we should do early on is find
> out the component heights (thicknesses) of those two chips.
Soldering an IC to a board isn't mechanically precise. A lot of
things affect the thickness of a solder joint, and the differences between
joint thicknesses on the same IC. So besides differences in nominal height,
you also get tilt. Thermal interfaces thick enough and soft enough to
compensate for that tend to have fairly high thermal resistances. Also,
board warp and twist can add to coplanarity discrepancies between
components.
All of that can be solved, but it gets into the realm of
conduction-cooled aerospace boards, with assembly jigs and highly engineered
heat sinks and thermal interfaces. I think it's a lot easier to use
individual heat sinks.
_______________________________________________
Open-graphics mailing list
[email protected]
http://lists.duskglow.com/mailman/listinfo/open-graphics
List service provided by Duskglow Consulting, LLC (www.duskglow.com)
