Re: compact PCI clock distribution

["Peter Marek" <peter.marek@marekmicro.de>]

Hi,

Please consider the loading issues for CPCI. Only two loads (i.e. two chips)
allowed on the system board.
That's why most people use a PCI2PCI bridge chip between the system board's
local PCI bus and the CPCI backplane. The PCI bridges available usually have
PCI clock buffers for teh backplkane built into the chip.

In case you don't use a PCI bridge, you may just use a oscillator and a zero
delay clock buffer. The skew compensation can easily be done in the layout.
We have used the Cy2309 and have made good experience. Pericom also works
fine. (This does not mean that other vendor's solutions won't work).

regards,

Peter Marek
General Director
MarekMicro GmbH
tel.: 049-9621-9732-110
fax: 049-9621-9732-199
www.marekmicro.de

----- Original Message -----
From: "Nico Fleurinck" <nico.fleurinck@verhaert.com>
To: <pci-sig@znyx.com>
Sent: Wednesday, November 06, 2002 3:56 PM
Subject: compact PCI clock distribution


> Dear experts,
>
> For my compact PCI system board design i'm thinking to use the following
> components for the clock distribution:
> An oscillator that generates the 33MHz PCI clock
> A ROBOCLOCK CY7B991V of cypress for the skew regulation
> A zero delay buffer of cypress CY2309 for the generation of the 7 clock
> signals for the peripheral boards.
> (details about the components can be found at  www.cypress.com )
>
> Is this a correct way to do the clock distribution?
> If you have experiences with the design of clock distibution of compact
PCI
> or PCI board please send me some feedback.
> If you have a better way to do the clock distribution do not hesitate to
> tell me that, i'm very interesting to hear your approach.
> Thank you very mutch for reading this mail and taking some time for
sending
> me some feedback.
>
> Best regards,
> Nico
>
>
>
> Nico Fleurinck
> Junior Design Engineer
> VERHAERT Satellites & Platforms
> Hogenakkerhoekstraat 21
> B-9150 Kruibeke
>
> Tel : +32 3 250.1984
> Fax : +32 3 254.1008
> e-mail : nico.fleurinck@verhaert.com
> Visit us : www.verhaert.com
>
>
>