Re: [SI-LIST] : PCB track length and ringing

Dmitri Kuznetsov (vdm@iname.com)
Wed, 24 Sep 1997 17:14:46 -0700

I would like to point out the effect the switching speed and
interconnect length have on the ringing.

The magnitude of ringing cannot be larger than the transient slew rate
times the round-trip delay thru the trace. For the ringing to reach its
maximum magnitude under given terminations, the interconnect round-trip
delay has to be greater than the switching time.

As a result, even for large reflections and small loss, the ringing may
be almost unnoticeable in slower circuits and shorter interconnects, and
becomes more pronounced as switching speed and interconnect length
increase.

Regards,
-- Dmitri

=======================================================
Dmitri Kuznetsov, Ph.D.
R&D Engineer

Avant! Corporation e-mail: vdm@avanticorp.com
46871 Bayside Pkwy. Tel: (510)413-8631
Fremont, CA 94538 Fax: (510)413-7706
=======================================================

Gopala Krishna M.R. wrote:
>
> Hi,
>
> Can someone explain how the PCB (printed circuit board) track (signal
> trace) length causes ringing in the High Speed Digital Signal systems.
>
> Regards,
> Gopalkrishna