Re: [SI-LIST] : Stackup Extraction

Mike Mayer (Mike.Mayer@cp.artesyn.com)
Thu, 19 Aug 1999 10:32:53 -0500 (CDT)

>>>>> "Michael" == Michael C Greim <mgreim@dnaent.com> writes:

> Here's something that you might not have considered. Other than
> edge connector boards where you are tied to a specific card
> thickness most other systems are specified in terms of card
> guide thickness. By performing milling on the top and bottom
> sides of card in the guide area allows the designer the
> flexibility to use substrate thicknesses and copper weights that
> he needs while meeting the requirements of the system. This is
> easily the most cost effective way to get there from here
> compared with esoteric materials or low yield thicknesses of
> material or traces. This has worked very well for us in the
> past.

> Michael

I have thought about it, but there are specs like CompactPCI that have
a board thickness spec (1.6mm +/- .2mm). I don't know why actually --
as long as the component side is in the same place (so that the
backplane connectors mate properly) and the board edges are the
correct thickness it should not matter. A thicker board would need to
have a reduced height on the back of the board to keep out of the
"board envelope" area of the board next to it in the chassis. I
haven't looked into the specific board in question to see if the
height of components on the back of the board was a factor.

-- 
=============================================================================
Mike Mayer                               Artesyn Communication Products, Inc
                                         Madison, WI
                                         http://www.artesyn.com/cp
=============================================================================

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