1
GATE EE 2001
Subjective
+5
-0
The transistor in the amplifier circuit shown in the figure is biased at $${{\rm I}_C} = mA.$$ Use $${V_T}\left( { = {{kT} \over q}} \right) = 26\,mV,$$ $${\beta _0} = 2000,\,{r_b} = 0$$ and $${r_0} \Rightarrow \infty$$
$$(a)$$ Determine the AC small signal midband voltage gain $$\left( {{\raise0.5ex\hbox{\scriptstyle {{V_o}}} \kern-0.1em/\kern-0.15em \lower0.25ex\hbox{\scriptstyle {{V_i}}}}} \right)$$ of the circuit
$$(b)$$ Determine the required value of $${C_E}$$ for the circuit to have a lower cutoff frequency of $$10Hz$$
2
GATE EE 2000
Subjective
+5
-0
A current amplifier has an input resistance of $$10\Omega ,$$ an output resistance of $$10\,\,k\Omega$$ and a Current gain of $$1000.$$ It is feed by a current source having a source resistance of $$10$$ $$k\Omega$$ and its output connected to a $$10\,\,k\Omega$$ load resistance. Find the voltage gain and the power gain
3
GATE EE 1999
Subjective
+5
-0
For the small signal $$BJT$$ amplifier shown in given figure. Determine at $$1$$ $$kHz$$ the following

$$(a)$$ $$\,\,\,\,\,\,\,\,$$ Quiescent collector current $${{\rm I}_{CQ}}$$
$$(b)$$ $$\,\,\,\,\,\,\,\,$$ Small signal voltage gain $${{{V_o}} \over {{V_i}}}$$
$$(c)$$ $$\,\,\,\,\,\,\,\,$$ Max. possible swing of the collector current.

4
GATE EE 1992
Subjective
+5
-0
For the $$JFET$$ amplifier shown in figure $$\mu = 100,\,{r_d} = 50k\Omega$$
$$(i)$$ Draw the $$AC$$ equivalent circuit
$$(ii)$$ Find the voltage gain of the amp
EXAM MAP
Medical
NEET