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(a) Obtain an expression for V0 in terms of Vs, R, and the reverse saturation current Is of the transiostor.
(b) If R = 1$$\Omega $$, Is = 1pA and the thermal voltage VT = 25mV, then what is the value of the output voltage V0 for an input voltage Vs = 1V?
(c) Suppose that the transistor in the feedback path is replaced by a p-n junction diode with a reverse saturation current of Is. The p-side of the diode is connected to node A and the n-side to node B. Then what is the expression for V0 in terms Vs, R and Is ?
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The characteristics of the diode are given by the relation I = Is $$\left[ {{e^{{{qV} \over {KT}}}} - 1} \right],$$
Where V is the forward voltage across the diode
(a)Express V0 as a function of Vi assuming Vi> 0.
(b)If R = 100K$$\Omega $$ , Is = 1$$\mu $$A and $${{KT} \over q}\,\, = \,\,25mV$$
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