Re: +3.3V should be created on the PWB using a regulator

[Ivor Bowden <ivor@peritek.com>]

At 08:24 AM 6/28/00 -0700, Mike Dini wrote:
>I would like to comment that we do not believe a PCI board designer can 
>guarantee that +3.3V is provided from the backplane in any PCI-based system 
>that is not 66MHz.  The motherboard may have the connections, and be v2.2 
>compliant, but it still is quite possible that the manufacturer of the 
>computer didn't attache a power supply to the motherboard.

Isn't it true that EVERY PCIv2.2 system MUST have 3.3V on the backplane?
So if you state your card will only run in a PCI v2.2 system, or v2.x if
3.3V is present on the backplane you should be OK. But if you are targeting
the commercial market it would probably be a good idea to have the regulator
to support all the old PCs out there.

>For the present and into the near future, all PCI designs that are not 
>66MHz should create +3.3V from +5v/+12v using a regulator.
>
>Mike Dini
>
>
>