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FIGURE 11.32 Measurement of open-circuit voltage and short-circuit current.
FIGURE 11.33 i-v characteristic of exponential resistor.
The following are expressions for the true short-circuit current and open-circuit voltage.
i N = i SC 1 + r m
------
R T
(11.26)
v T = v OC 1 + R T
------
r m
where i N is the ideal Norton current, v T the Thévenin voltage, and R T the true Thévenin resistance.
Nonlinear Circuit Elements
Description of Nonlinear Elements
There are a number of useful cases in which a simple functional relationship exists between voltage and
current in a nonlinear circuit element. For example, Fig. 11.33 depicts an element with an exponential
i-v characteristic, described by the following equations:
i = I 0 e , v > 0
a v
(11.27)
i = – I 0 , v ≤ 0
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