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Article: The inductance of a transmission line: understanding the relationship between total loop inductance of a line, time delay and its characteristic impedance. (No Myths Allowed).
- Article from:
- Printed Circuit Design & Manufacture
- Article date:
- July 1, 2003
- Author:
CopyrightCOPYRIGHT 2003 UP Media Group, Inc. This material is published under license from the publisher through the Gale Group, Farmington Hills, Michigan. All inquiries regarding rights should be directed to the Gale Group. (Hide copyright information)
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IN EVERY UNIFORM transmission line there is a simple relationship between its characteristic impedance, its time delay and its loop inductance. This applies to every line, whether a microstrip, stripline, coplanar or even twisted-pair. The only criterion is that it be of uniform cross-section, which is, of course, the definition of controlled impedance interconnect. If we know any two of the following--time delay (TD), characteristic impedance ([Z.sub.0]) or loop inductance (L)--we can find the third.
Every interconnect in every board is really a transmission line. It takes two conductors to make up a transmission line. One we label the signal path; the other we ...