RE: [SI-LIST] : Overshoot/Undershoot

Barnes, Larry ([email protected])
Mon, 23 Feb 98 17:09:00 MST


Suppose you are transiting from voltage level A to voltage level B. If
the signal goes past B then settles back to B, probably with some
oscillations around B, you have overshoot. If the signal doesn't make it
to B, or gets to B some time later than you desired you have undershoot.
If the signal gets to B without going over or under you have the ideal
condition, or from control theory, a signal that is critically damped.
To further confuse things, overshoot implies under-damping and
undershoot implies over-damping

Larry Barnes
Symbios Inc.

From: Mike Mayer[SMTP:[email protected]]
Sent: Monday, February 23, 1998 3:52 PM
To: [email protected]
Subject: Re: [SI-LIST] : Overshoot/Undershoot

=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

So for those of us who have only heard "undershoot" applied to
negative-going overshoot, what is the correct definition of

Mike Mayer Artesyn Technologies - Communication Products