(1) Clemson University
(2) Juniper Networks
(3) University of Missouri‐Rolla
EMCCompo 2007
6th International Workshop on
Electromagnetic Compatibility of Integrated Circuits
Torino, November 28th-30th 2007
Using Electric and Magnetic
“Moments” to Characterize IC
Coupling to Cables and Enclosures
T. Hubing (1), S. Deng (2), and D. Beetner (3)
EMCCompo 2007
Torino, 28th-30th November, 2007
Introduction
ICs are often the source of radiated energy, but usually not not the
“antenna”.
ICs couple to the structures that serve as antennas conducted,
electric‐field, or magnetic‐field coupling.
The electric and magnetic field coupling from an IC can be quantified
by measurements using a TEM Cell and a hybrid coupler.
These measurement results can be expressed as electric or magnetic
moments that fully describe an ICs ability to couple to nearby objects.
EMCCompo 2007
Torino, 28th-30th November, 2007
Hybrid TEM Cell Test Set-Up
A hybrid can be used to
differentiate electric and magnetic
field coupling.
The A-B output indicates the
amount of magnetic field coupling.
The A+B output indicates the
amount of electric field coupling.
EMCCompo 2007
Torino, 28th-30th November, 2007
Hybrid TEM Cell Electric Field Coupling
Electric
Moment
EMCCompo 2007
Torino, 28th-30th November, 2007
Hybrid TEM Cell Magnetic Field Coupling
Magnetic
Moment
EMCCompo 2007
Torino, 28th-30th November, 2007
Measurement Test Set-Up
EMCCompo 2007
Torino, 28th-30th November, 2007
Model vs. Measurement
EMCCompo 2007
Torino, 28th-30th November, 2007
Maximum Emissions Estimate
l
1 m
EMCCompo 2007
Torino, 28th-30th November, 2007
Conclusions
Measurements of an integrated circuit in a hybrid TEM cell
configuration can be used to obtain values for the “electric
moment” and “magnetic moment” associated with an IC as
it is configured on a given circuit board.
ICs with smaller moments are less likely to couple to other
parts of a system resulting in unintentio