Small Signal Modeling · Analog Electronics · GATE EE

Marks 1

For an ideal MOSFET biased in saturation, the magnitude of the small signal current gain for a common drain amplifier is

GATE EE 2022

In the single stage transistor amplifier circuit shown in figure, the capacitor $${C_E}$$ is removed. Then the ac small signal midband voltage gain of the amplifier

GATE EE 2001

In the transistor amplifier shown in figure, the ratio of small signal voltage gain when the emitter resistor is bypassed by the capacitor $$'{C_e}'$$ to when it is not bypassed. (Assuming of simplified approximate $$h$$- parameter model for transistor) is

GATE EE 1996

Marks 2

The transconductance $${g_m}$$ of the transistor shown in figure is $$10$$ $$mS.$$ The value of input resistance $${R_{in}}$$ is

GATE EE 2004

Marks 5

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 $$10Hz$$

GATE EE 2001

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

GATE EE 2000

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.

GATE EE 1999

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

GATE EE 1992

Figure shows a common emitter amplifier

GATE EE 1991 Analog Electronics - Small Signal Modeling Question 3 English 1

$$(a)$$ 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.

GATE EE 1991