[SI-LIST] Re: 2.5Gbit connectors and cables
- From: "john lipsius" <johnlipsius@xxxxxxxxx>
- To: <jtreeve@xxxxxxxxxxxxxxx>, <si-list@xxxxxxxxxxxxx>
- Date: Tue, 1 Oct 2002 13:57:29 -0700
Jeff,
Assuming coax interconnect....
1. If the board pairs are 100ohm Zdiff pairs, then interconnecting with
coax will present a pretty large problem in that you'll have two zeven/
zodd discontinuities, plus the coax connector stubs in the pcb.
2. Instead, I would route the board traces as microstrip single-ended on
the opposite surface from the the smb mounting surface, or use SMT
coax connectors, to mitigate the stub. Further, I would use 0402 series
R to attenuate the signal and slow the edges, also to mitigate the
discontinuities.
You can always put in a 0 ohm value if needed, but driver amplitude
control is better than this approach, if available. Also, experiment
with disabling any pre-emphasis in the driver since the link is short and
discontinuous.
None of the above replaces the need to simulate or prototype.
-John
----- Original Message -----
From: "Jeff Reeve" <jtreeve@xxxxxxxxxxxxxxx>
To: <si-list@xxxxxxxxxxxxx>
Sent: Monday, September 30, 2002 9:43 PM
Subject: [SI-LIST] 2.5Gbit connectors and cables
>
> SI-List,
>
> I need to specify a connector and cable to accomodate board to board
> interconnect of four 2.5Gbps differential pairs. The length of the cable
> would be about 2" between boards and the trace on each PCB to the SerDes
> would be <3" for a total length of 8". Any suggestions, solutions or
> pointers would be greatly appreciated.
>
> Thanks in advance
> Jeff
>
> ------------------------------------------------------------------
> To unsubscribe from si-list:
> si-list-request@xxxxxxxxxxxxx with 'unsubscribe' in the Subject field
>
> or to administer your membership from a web page, go to:
> //www.freelists.org/webpage/si-list
>
> For help:
> si-list-request@xxxxxxxxxxxxx with 'help' in the Subject field
>
> List archives are viewable at:
> //www.freelists.org/archives/si-list
> or at our remote archives:
> http://groups.yahoo.com/group/si-list/messages
> Old (prior to June 6, 2001) list archives are viewable at:
> http://www.qsl.net/wb6tpu
>
------------------------------------------------------------------
To unsubscribe from si-list:
si-list-request@xxxxxxxxxxxxx with 'unsubscribe' in the Subject field
or to administer your membership from a web page, go to:
//www.freelists.org/webpage/si-list
For help:
si-list-request@xxxxxxxxxxxxx with 'help' in the Subject field
List archives are viewable at:
//www.freelists.org/archives/si-list
or at our remote archives:
http://groups.yahoo.com/group/si-list/messages
Old (prior to June 6, 2001) list archives are viewable at:
http://www.qsl.net/wb6tpu
Other related posts:
