Agilent Technologies 4155C, User Manual

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Agilent 4155C/4156C VXIplug&play Driver User’s Guide, Edition 4 7-5
Sample Application Programs Using VEE
Introduction
Definition of Vth
The threshold voltage (Vth) is extracted by a linear interpolation using two
measurement points, which are the nearest from the targeted point for both higher
and lower directions. The targeted point (Vg_extract,Id_target) is an ideal point,
which indicates the Id_target value on the line through the two measurement points
on the Id-Vg curve. See Figure 7-1.
Figure 7-1 Definition of Vth
Id
Vg
If Id(n)=Id_target, Vth=Vg(n)
If Id(n)<>Id_target, Vth=Vg_extract
(Vg(n+1),Id(n+1))
(Vg(n),Id(n))
(Vg_extract,Id_target)
Definition of Vth