1
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
2
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.
3
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
$$(i)$$ Draw the $$AC$$ equivalent circuit
$$(ii)$$ Find the voltage gain of the amp
4
GATE EE 1991
Subjective
+5
-0
Figure shows a common emitter amplifier
$$(a)$$ Simplify the circuit by applying thevenin's theorem to biasing network $${R_1},{R_2}$$ at
$$\,\,\,\,\,\,\,$$ the base of the transistor.
$$(b)$$ Assuming $${C_s}$$ to be a short for frequency range considered. Draw the small signal
$$\,\,\,\,\,\,\,$$ $$a.c.$$ model of the circuit obtained in $$(a)$$ by using the simple model for the
$$\,\,\,\,\,\,\,$$ transistor shown in figure.
$$(c)$$ Evaluate the small signal gain $$\left( {{{{V_0}} \over {{V_i}}}} \right)$$ of the amplifier.
Questions Asked from Small Signal Modeling (Marks 5)
Number in Brackets after Paper Indicates No. of Questions
GATE EE Subjects
Electric Circuits
Electromagnetic Fields
Signals and Systems
Electrical Machines
Engineering Mathematics
General Aptitude
Power System Analysis
Electrical and Electronics Measurement
Analog Electronics
Control Systems
Power Electronics