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Re: Double height PCI cards
You need to send your email to: pci-sig@znyx.com. I'll post this reply and
your quoted email to the board since it appears you sent it directly to
me...
As to the PCI card issue you have, I did dev board a few months ago for the
now out-of-business Acorn Networks Genflow OC48 part...
It was way too tall and, as in your application, 5 times outside of the 25W
limit. To get around this (remember this is a development board for
engineers evaluating a chip) we used a drive connector, similar to those
found on hard drives.
This allowed us to satisfy the power requirements by using on-board
regulators for the many power rails. We did power the PLX PCI chip using
the PCI buss power; since it was universal it had an onboard 3V# reg for 5
volt slots.
A low resolution screenshot is available on my web page
http://home1.gte.net/wamnet.
Just click on the Product Design and Development link.
Here's some info about it (for anyone that cares):
OC48 traffic management device
BGA's included 901, 600, 388 and 432 ball devices
806 components
5 clock domains 4 of which were >100Mhz
5 busses including SDRAM configured for 128bit wide data path, static RAMS
for DES, SCH, XCH, CAM
many of Mictor connectors for logic analysers
UTOPIA to the Framer
LVPECL to the transponder
12 layer - 6 routing 6 planes
so many split planes I can't remember
all signals at 50 ohm with diff routing for the LVPECL
all PLX to PCI were 60-100 ohm routed to 2.2 spec.
you can see the 4 main regulators on the right below the drive connector.
This allowed us to get well over 50 watts from a 350W PC-style supply...
Andrew Ircha wrote:
> This is my first posting to this list. Forgive me if I've posted to the
> wrong address, or if the threading doesn't work.
>
> If anyone can point me to the rules of this list, and/or an FAQ I'd be
> grateful.
>
> I have an application where I intend to have a card which plugs into a
> PCI slot of a PC. My card will be much too tall to stay within the
> 14.48mm height restriction, and in any case is likely to exceed the 25W
> per slot power limit.
>
> My plan was to have a PCI card + daughter card arrangement with the
> daughter card plugging into the adjacent PCI slot for extra power.
>
> Would this violate the PCI mechanical requirements? Does that matter?
>
> Would 2.54mm connectors be suitable as the local signal connector
> between cards (at TTL levels, not PCI levels)?
>
> How do other do this? 3D Labs' Wildcats do something like this, but I
> don't know how they connect the local bus signals.
>
> Many thanks,
>
> Andrew Ircha
--
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)