[SI-LIST] Re: Twisting of differential pair traces
- From: "Nitin Sood" <Nitin.Sood@xxxxxxx>
- To: <si-list@xxxxxxxxxxxxx>
- Date: Fri, 23 Jun 2006 14:13:48 -0700
Joaquin,
If you can minimize the intermediate traversal of traces between the =
layers ,
you should be ok.=20
You can do a quick simulation to see the effect. I have seen minimal =
effect
on gigabit traces with this scenario Of twisting the differential =
signals.
Regards
Nitin Sood
-----Original Message-----
From: si-list-bounce@xxxxxxxxxxxxx [mailto:si-list-bounce@xxxxxxxxxxxxx] =
On
Behalf Of jain.nitin@xxxxxxxxx
Sent: Thursday, June 22, 2006 12:28 AM
To: JFonseca@xxxxxxxxx; si-list@xxxxxxxxxxxxx
Subject: [SI-LIST] Re: Twisting of differential pair traces
Hi Joaquin,
There is no problem in doing so but only when you are trying to twist, =
you=3D
will introduce an extra length for one of the trace. In other words =
you=3D
will introduce some skew b/w 'p' & 'n' trace. If that skew is under =
your=3D
tolerance level, no issues otherwise you will have to compensate for =
that=3D
skew maintaining your 100ohm differential impedance. If you have =
loosely=3D
coupled traces matching p & n length is not a problem. You can do it=3D
anywhere b/w your driver & receiver. But if you have edge coupled =
traces,=3D
the best way is to add extra trace length to p/n (which ever is short) =
at=3D
driver or receiver pins only. Hope it helps.
With regards,
Nitin=3D0D
-----Original Message-----
From: si-list-bounce@xxxxxxxxxxxxx [mailto:si-list-bounce@xxxxxxxxxxxxx] =
On=3D
Behalf Of Fonseca, Joaquin
Sent: Thursday, June 22, 2006 11:39 AM
To: si-list@xxxxxxxxxxxxx
Subject: [SI-LIST] Twisting of differential pair traces
I have a question regarding routing differential signals on a =
board.=3D0D For
the case that the pair of traces of a given differential pair travels=3D =
from
layer to layer using vias, what is the effect if the traces are=3D =
allowed to
twist?. That is, what is the effect of having the plus trace on=3D one =
side of
the pair on a layer, and then having it on the other side on=3D another =
layer
(after transitioning thru vias)? (I hope I am able to=3D explain the =
"twist"
issue).
Any comments are welcome.
Regards,
Joaqu=3DEDn
------------------------------------------------------------------
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 FAQ wiki page is located at:
http://si-list.org/wiki/wiki.pl?Si-List_FAQ
List technical documents are available at:
http://www.si-list.org
List archives are viewable at: =3D0D
//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
=3D0D
The information contained in this electronic message and any attachments =
to=3D
this message are intended for the exclusive use of the addressee(s) =
and=3D may
contain proprietary, confidential or privileged information. If you=3D =
are not
the intended recipient, you should not disseminate, distribute or=3D =
copy this
e-mail. Please notify the sender immediately and destroy all=3D copies =
of this
message and any attachments.=3D0D
WARNING: Computer viruses can be transmitted via email. The recipient=3D
should check this email and any attachments for the presence of =
viruses.=3D
The company accepts no liability for any damage caused by any virus=3D
transmitted by this email.
=3D0D
www.wipro.com
------------------------------------------------------------------
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 FAQ wiki page is located at:
http://si-list.org/wiki/wiki.pl?Si-List_FAQ
List technical documents are available at:
http://www.si-list.org
List archives are viewable at: =20
//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
=20
------------------------------------------------------------------
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 FAQ wiki page is located at:
http://si-list.org/wiki/wiki.pl?Si-List_FAQ
List technical documents are available at:
http://www.si-list.org
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:
