Conductivity
Conductivity is used in EMI Analyst to calculate
characteristic impedance and to determine ac and dc resistance of . At low frequencies conductivity can have
a noticeable effect of characteristic impedance.
To change the conductivity, select the material name from
the drop-down list box. The corresponding relative conductivity will be
displayed in the adjacent text box.
Absolute conductivity is equal to conductivity of copper
divided by the relative conductivity.
Several hypothetical semiconductors are included in the
list of materials available from the drop-down list box. The values of
these materials, while not specific to any known materials, allow calculations
to be carried out for a broad range of lossy materials. These
semiconductors may be helpful in evaluating non-metal conductors such as
carbon-fiber ground planes or ferrite-loaded wiring.
Tech Note - Conductivity
Relative
conductivity is a measure of the material conductivity, relative to that of pure
copper. A material having a relative conductivity of 0.1, for example, is
one-tenth as conductive as (10 times more resistive than) pure copper.
Selecting a material other than copper increases the complexity of the
calculations and may increase calculation time slightly. Generally the
conductivity of the conductors has negligible effect. However, for very
long cables, very high frequencies, or low conductivity conductors, results may
be different than for copper conductors. See Conductors for more information. More:
 Permeability
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