Teledyne T3SP Series Operator's Manual page 42

Click the menu entry Extra
A dialog is raised, showing a table with calculated impe-
dance slopes of selected samples. The mean value can now
be applied to the selected samples.
Please note: another suitable method for determining reasonable val-
ues for Ohmic Losses is to measure the same line from both ends and to
adjust the value until the measured wave impedance of the beginning
of the first measurement matches to the end of the second.
Remark: use the automatic slope determination only if you are familiar
with this topic. It is recommended to use this function only in combi-
nation with plain lines (as commonly used on impedance test coupons)
with a length of at least 50mm.
•
In the Geometry field the definitions for microstrip- and striplines (sin-
gle-ended and/or differential) can be set. In the context of the impe-
dance measurements the values are used to calculate the propagation
velocity. If another line type is selected, they have no influence and
can be set to some default values (e.g. h = 1mm, w = 1mm, t = 0.1mm).
Remark: the propagation velocity depends on the dielectric constant, the
line-type and (in case of e.g. top/bottom-layer lines) on the particular ge-
ometry. Complex models described in specialized literature are integrated
in the software. Please be aware, that these models cover a wide range of
parameters and make no claim of being exhaustive.
Please note: the roughness of the conductor is not taken into account.
•
The y-tolerance mask can be defined by setting the nominal impe-
dance and tolerance values.
•
The tolerance x-axis [ns] can directly be set as follows:
T3SP-Series Operator's Manual
Calculate Impedance Slopes.
42
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