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Re: PCI board outline
Ah, actually the outline Protel's template generates is a bit off... if you
check the actual dimensions of one of the keying slots on the universal 32-bit
PCI template (I used the short one) it's a little wide (~5 mils).
Been using Protel for about 8 years now (due to the fact I almost sued another
EDA tool vendor after releasing their first Windows version). It's a nice
product. I've made many $80.00 phone calls to Australia to talk to some of the
team and got the feeling they have their act together.
If you need a mid-priced EDA tool, I'd say you can't get much better. Good
forum for Protel users currently on techserve too (Visit
http://www.techservinc.com/protelusers/subscrib.html to subscribe)
Just turned another crypto accelerator for my day job. Looks good. The
first 4
protos of the original 60 Mbit 3DES card we did were a bit loose causing the
card to slightly mis-register the fingers with the contacts in a standard AMP
PCI MB connector. I then checked the PCI spec and sure enough, the one slot
was
a little large and was not what the template dimensions said it should be (the
dimensions in the Protel template aren't "live" dimensions). I then used
Solidworks to accurately model the PCI card from the PCI spec (needed it for
the chassis mechanicals anyway) and then brought this into ACAD as an ACIS
parasolid. I then exported a 2D outline from ACAD as DXF V12 and brought that
into Protel 99SE SP5. I was then able to re-export the finished board back to
DXF, strip out the layer info leaving the mechanical 4 layer (which was the
correct outline from the solid), create the panel with tab routes (with the
correct clearance at the corners for a standard .093" end mill) and mouse
bites
of the panel (which was interesting since you have to leave the fingers open
for plating extensions and chamfering), then import that into Camtastic DE,
bring in the gerbers and drill; copy, rotate the copy and place it using
object
snaps and re-export the panel gerbers and drill. To keep from getting DRC
violations in Protel, I used two more mechanical layers for the finger
plating
extensions and merged this to the top and bottom layers in the gerber CAM
tool.
The CM we used love the data files and said it was the best package he'd ever
recieved; made it easy to bring into his pick and place front end tool.
A bit of work but well worth the effort. The production run went well and the
cards fit nicely aligned regardless of chassis and or bracket tolerance (I use
Purcell and Gompf).
Since then I've done many more cards and PICMG backplanes with very acurate
results. In one design we had less than 5mil tolerances for a single U rack
mount PICMG. Using the techniques listed above and extending that technique
for
the complete chassis, backplane, and card design everthing fit perfectly. The
old-timer at the metal shop was a bit amazed at how tight the design was.
An aside: check out www.ultracad.com for some cool tools for calculating
various trace geometries. They also have some good info concerning split
planes
and other PCB layout related stuff.
--
WAM
http://home1.gte.net/wamnet
http://members.aol.com/wamnet
"Two things are infinite: the universe and human stupidity;
and I'm not even sure about the universe."
~~Albert Einstein (1879-1955)
burched - tony burch wrote:
> Duncan,
>
> I'd just like to second Henry's suggestion.
> The Protel 99SE Board Wizard generates a correct
> outline, edge connector, mounting holes and
> track and component keepouts as defined
> by the PCI spec. It was easy to use - it
> will generate outlines for short or long
> cards, 5V, 3.3V or universal - the wizard
> gives you the options.
>
> Just this week I plugged in a PCI card that
> was designed using Protel 99SE. No problems,
> very happy.
>
> I have no affiliation with Protel. I just use
> their products.
>
> Best regards
>
> Tony Burch
>
> www.BurchED.com.au
> Lowest cost, easiest-to-use
> FPGA prototyping kits!
>
> > Duncan,
> >
> >
> > Why don't you try an EDA, such as Protel. Protel create a PCI PCB
> > automatically with detaled mechanical information.
> >
> > Henry Gong
> > Cisco Systems
> > .
> >
> > Duncan Ross wrote:
> >
> > > Can anyone provide me with a mechanical drawing of a PCI BUS board
> outline?
> > > I am only concerned with profile details, PCI BUS edge connector
> position
> > > and pin numbering. A PDF format document or a web address for download
> > > would be great. This information, strangely, does not seem to be freely
> > > available from PCISIG or anywhere on the internet??
> > >
> > > Working for a poor University, we can not afford fees to obtain this
> > > information :-(
> > >
> > > Help much appreciated
> > >
> > > Thanks
> > >
> > > Duncan Ross, Head Electronics Technician
> > > Space Research Centre
> > > Department of Physics and Astronomy
> > > University of Leicester
> > > University Road
> > > Leicester
> > > LE1 7RH
> > >
> > > Tel +44 (116) 2523012
> > > Fax +44 (116) 2522464
> > >
> > > Space Research Centre web pages at: http://www.src.le.ac.uk/
> > > Electronics workshop web pages at: http://www.star.le.ac.uk/~dro/
> >