RE: [SI-LIST] : Overshoot/Undershoot

Andrew Ingraham (
Tue, 24 Feb 1998 08:23:40 -0500

Thanks for this discussion; it has reminded me that it was only a short
time ago that I always used "overshoot" for both positive and negative
directions, and "undershoot" was different.

Funny how just a few years of dealing almost exclusively with non-ECL
digital logic, changes one's perspective. Between co-workers and IC
vendors, and without realizing it, I have gotten completely into the
habit of using "undershoot" to mean negative overshoot.

It's shorter and easier to say... ;-)

Even IC data sheets have changed to using "undershoot" to mean "negative
overshoot." I have some examples on my desk.

For kicks, I pulled out my old MECL System Design Handbook. Figure 4-1
(in my copy) illustrates overshoot and undershoot as it used to be.
Other figures in the book also show the cases where the signal plateaus
before reaching the desired value.

I tend to agree that language is what we make it ... as long as we all
understand each other.