[SI-LIST] : Re: [SI-LIST] - Overshoot/U

MARK GAILUS (mark_gailus@tcsmail.tcs.teradyne.com)
24 Feb 1998 13:31:01 -0400

RE>>[SI-LIST] : Overshoot/Undershoot 2/24/98

I whole-heartedly agree with Mr. Sessions's last statement (appended). As
digital designers find themselves increasingly forced to cross over into the
analog world of signal description to analyze performance, they would serve
themselves and others well by utilizing existing carefully crafted
terminology, when available. This also applies to areas of overlap with
existing RF and microwave design.

--Mark Gailus
Teradyne, Inc.
--------------------------------------
Date: 2/24/98 11:17 AM
To: MARK GAILUS
From: Si List
Steve Williams wrote:
>
> >> I have a question. When the term "undershoot" is used
> >> on this mail group is it to be interpreted as "negative overshoot"?
> >> Or in fact are some engineers having undershoot problems?
> >
> >Alas, 'tis true. For too many years the digital crowd, having
> >heard the term 'undershoot' but never really worked with it,
> >assumed that it was what is known more precisely, negative-going
> >overshoot. Books, articles, and instrumentation all made
> >this usage the only one known to many young and impressionable
> >engineers.
>
> English is the language of democracy, I guess, and majority rules. So what
> do you call it when a signal doesn't reach its intended level on the first
> pass? Maybe if don't have a name for it, it will just go away...

Except that there's a large and valuable body of literature which
has always used 'undershoot' consistently. That usage is in fact
reflected in the IEEE standard lexicon (standard number slips
mind). We've had quite a bit of success in getting instrument
and software manufacturers to comply with the standard, so we
may as well continue and get the digital community to clean up its
act rather than change the standard, the tools, and the analog
and control groups.

-- 
D. C. Sessions
dc.sessions@tempe.vlsi.com