Re: [SI-LIST] : Differential Clock Routing

Richard Koshak (rkoshak@viewlogic.com)
Thu, 08 Jan 1998 15:49:44 -0500

I can help you with your second question. You don't need to use connect
node for this. Differential devices are identified by the XTK device models
for the components on the nets. There is additional information in the part
of the model that associates drivers and receivers with pins that
identifies differential pairs. There are good examples in the modeling
documentation. When the translator ,isf2xtk, sees these models on the nets
it creates one simulatable differential net in the topology file for xns.
The simulator drives both ends of the pair simultaneously so that you can
analyze the nets the way they are meant to be used.

---------------At 09:02 AM 1/8/98 -0700, skolli@smartm.com you
wrote------------------

Si-list Subsribers,

I am looking for information on the following. Your help would be much
appreciated.

1) Guidelines on how differential clock routing should be done. If any
one can point me to some availble "printed material" would do me a
great service. The clocks will be running at 125-150MHz.

2) How do you simulate this kind of differential transmission lines
using QUAD XTK tools. They have some thing called a "Connect_Node"
which is supposed to be used for defining the topology. However there is
very little explanation on one can use it.

Thanks.