Re: [SI-LIST] : TDR formula

Dr. Edward P. Sayre (esayre@nesa.com)
Tue, 29 Jul 1997 17:46:04 -0400

To a first approximation, the inductance of a single inductive discontinuity
on a trnasmission line of impedance Zo is given by:

L = 2*(Ref. Coef.)*Zo*Tr,

where: Tr is the risetime of the incident pulse.

As a matter of practicality, you can also use for Tr the width of the half
height of the inductive bump. It works better most of the time.

Dial into our web site and look if the seminars on line are of interest to
you. We cover this and many other SI topics from a theoretical and
practical viewpoint. We are designers ourselves.

ed sayre

At 10:15 AM 7/28/97 -0400, you wrote:
>Can anybody tell me the formula for inductance calculation using the
>bump height of TDR trace?
>Since the network that I am on is not subscribed to SI-List, please send
>it to me directly.
>
>Thanks in advance.
>
>
>

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