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UTOPIA interface signal traces

Started by Nithin April 29, 2005
Hi
I am new to UTOPIA interface. I would like to know how critical it is
to have matched lengths for UTOPIA data and clock traces on PCB with
multiple processers (all processer having UTOPIA interface).

It would be nice if somebody could reply as soon as possible.

Regards
Nithin

Hi Nithin,

It depends. Look inside the datasheets of your utopia transmitter and 
receiver to see the timing requirements. If I'm looking e.g. in my 
IXP425 datasheet at AC characteristics I can find the recommended 
setup/hold time requirements for the UTOPIA receiver. With these values 
I can go to the transmitter timings and calculate the reserve between 
transmitter timing and receiver timing and the rest is available for 
everything that happens (bad edges, length differences between clock and 
signals, ...)  between transmitter and receiver.

I hope this helps,

Michael


PS: Remove the ABC chars to get my correct e-mail.


Nithin wrote:
> Hi > I am new to UTOPIA interface. I would like to know how critical it is > to have matched lengths for UTOPIA data and clock traces on PCB with > multiple processers (all processer having UTOPIA interface). > > It would be nice if somebody could reply as soon as possible. > > Regards > Nithin >
An inch or two is not going to make much of a difference if you ar
talking about uotopia level 1/2 (50 Mhz).  You will have more of 
problem on the higher speed utopia busses.  You will however need t
watch clock distribution