Analog Electronics
Exam Duration: 45 Mins Total Questions : 30
The hybrid -\(\pi \) parameter values of gm,r\(\pi \) and r0 are
- (a)
24 mA/V, \(\infty \) , 5k\(\Omega \)
- (b)
24 mA/V, 5k\(\Omega \),\(\infty \)
- (c)
48 mA/V, 10 k \(\Omega \),18.4 k\(\Omega \)
- (d)
48 mA/V, 18.4 k \(\Omega \) ,10\(\Omega \)
When we say, S = 51 which means that
- (a)
IC increases 51 times as fast at ICO
- (b)
IC is 51 times greater than ICO
- (c)
IC is 51 times greater than IB
- (d)
None of the above
The p-MOS transistor in figure has parameters
\(V_{TP}=-1.2-V,{W\over L}=20\)
and Kp=30μA/V2
If ID =1 mA and VD = - 5 V, then values of Rs and RD
are
- (a)
4kΩ, 5.8kΩ
- (b)
4kΩ, 5kΩ
- (c)
5.87kΩ, 4kΩ
- (d)
6.98kΩ, 5kΩ
For the circuit shown below transistor parameters are VTN =2 V2 Kn =0.5 mA/V2 and ⋋.=0.The transistor is in saturation
If IDQ is to be 0.4 mA, the value of VCS,Q is
- (a)
5.14V
- (b)
4.36V
- (c)
2.89V
- (d)
1.83V
For the circuit shown below transistor parameters are VTN =2 V2 Kn =0.5 mA/V2 and ⋋.=0.The transistor is in saturation
The value of gm and ro are
- (a)
0.89 mS, infinite
- (b)
0.89 mS, ze
- (c)
1.48 mS, zero
- (d)
1.48 mS, infinite
In UJT relaxation oscillator, if supply voltage is doubled then, the amplitude of the voltage waveform across capacitor will
- (a)
get doubled
- (b)
reduce to half
- (c)
not change at all
- (d)
None of these
In the circuit given below, the CMRR of the op-amp is 30 dB. The magnitude of the V0 is
- (a)
2mV
- (b)
100mV
- (c)
200mV
- (d)
1mV
In the op-amp circuit shown below, it is desired that V0 = V2/3 - 2V1 what is the value of R to achieve Va?
- (a)
100kΩ
- (b)
40kΩ
- (c)
80kΩ
- (d)
30kΩ
The input voltage in shown below circuit is Vi = 5 sin rotmV. The current I0 is
- (a)
-2sin ωt μA
- (b)
-2.2sin ωt μA
- (c)
-5sin ωt μA
- (d)
zero
For half wave rectifier with capacitor input filter what will be the maximum voltage that will appear across the diode of an input AC of 10 V?
- (a)
10V
- (b)
14V
- (c)
28V
- (d)
1.5V
For a silicon diode, the incremental resistance at (c) room temperature and current 26 mA is
[Vr = 0.026 V, where VT=volt equivalent of temperature]
- (a)
2Ω
- (b)
1Ω
- (c)
10Ω
- (d)
20Ω
The diodes in the figure are ideal.
The transfer characteristics for - 20 V ≤ V1 ≤ 20 V is
- (a)
- (b)
- (c)
- (d)
None of these
Which of the following figures indicates the equivalent circuit for tunnel diode?
- (a)
- (b)
- (c)
- (d)
The operating state that distinguishes a Silicon Controlled Rectifier (SCR) from a diode
- (a)
\({20\over 3}V\)
- (b)
10V
- (c)
14V
- (d)
20V
The common-emitter forward current gain of the transistor shown is \({ \beta }_{ F }\) =100.
The transistor is operating in
- (a)
saturation region
- (b)
cut-off region
- (c)
reverse active region
- (d)
forward active region
The value of R for which the PMOS transistor in figure will be biased in linear region is
- (a)
220 \(\Omega \)
- (b)
470 \(\Omega \)
- (c)
680 \(\Omega \)
- (d)
1200 \(\Omega \)
The input signal Vin shown in the figure is a 1 kHz square wave voltage that alternates between + 7 V and -7 V with a 50% duty cycle. Bith transistors have the same current gain, which is large. The circuit delivers power to the load resistor RL. What is the efficiency of this circuit for the given input?
- (a)
46%
- (b)
55%
- (c)
63%
- (d)
92%
The current gain of the transistor shown in the below circuit is \(\beta \) = 150. The Q point (ICQ ,VCE Q) are
- (a)
0.418 mA and 20.4 V
- (b)
1.105 mA and 18.87 V
- (c)
0.915 mA and 16.23 V
- (d)
0.418 mA and 18.43 V
Which of the following devices cannot be used as controlled in stablizer?
- (a)
Power transistor
- (b)
Diac
- (c)
Triac
- (d)
SCR
For the following fixed bias configuration determined \(V_{ CEQ },V_{ BC }\)
- (a)
-11.6 V,12.3 V
- (b)
12.3 V, -11.6 V
- (c)
11.6 V, 12.3 V
- (d)
12.3 V,11.6 V
An n-p-n transistor has a beta cut-off frequency f\(\beta\) of 1 MHz and common-emitter short-circuit low frequency current gain \(\beta\)0 of 200. If unity gain frequency fT and the \(\alpha\) cut-off frequency
f\(\alpha\) respectively are
- (a)
200 MHz and 201 MHz
- (b)
200 MHz and 199 MHz
- (c)
199 MHz and 200 Mhz
- (d)
201 MHz and 200 MHz
The op-amp circuit shown below, represents a
- (a)
high-pass filter
- (b)
low-pass filter
- (c)
band-pass filter
- (d)
band-reject filter
For an n-p-n transistor connected as shown in below figure, VBE = 0.7 V. Given that reverse saturation current of the junction at room temperature 300 K is 10-13 A, the emitter current is
- (a)
30 mA
- (b)
39 mA
- (c)
49 mA
- (d)
20 mA
RC network shown in the given figure can provide a maximum theoratical phase shift of
- (a)
\(360^{ 0 }\)
- (b)
\(180^{ 0 }\)
- (c)
\(270^{ 0 }\)
- (d)
\(90^{ 0 }\)
For the circuit shown below calculate the output voltage
- (a)
\(\frac { 38 }{ 3 } \)
- (b)
\(\frac { 32 }{ 3 } \)
- (c)
\(\frac { 37 }{ 3 } \)
- (d)
None of these
In the voltage regulator shown in figure, the load current can vary from 100 mA to 500 mA. Assuming that the Zener diode is ideal (i.e., the Zener knee current is negligibly small and Zener resistance is zero in the breakdown region), the value of R is
- (a)
7 \(\Omega\)
- (b)
70 \(\Omega\)
- (c)
\(\frac { 70 }{ 3 } \Omega \)
- (d)
14 \(\Omega\)
For the transistor in figure \(\beta =100\) The value of voltage \(V_{ EC }\) is
- (a)
3.13 V
- (b)
4.24 V
- (c)
5.18 V
- (d)
13.1 V
An ideal op-amp is used to make an inverting amplifier The two input terminals of the op-amp are at same potential because
- (a)
the two potential terminals are directly shorted internally
- (b)
the input impedance of the op-amp is infinity
- (c)
the open-loop gain of the op amp is infinity
- (d)
CMRR is infinity
Let the magnitude of the gain in the inverting op-amp amplifier circuit shown in figure be X with switch \(S_{ 1 }\)open When the switch \(S_{ 1 }\) is closed the magnitude of gain becomes
- (a)
\(\frac { X }{ 2 } \)
- (b)
-X
- (c)
2X
- (d)
-2X
In the following transistor circuit VBE=0.7V, r=25mv/IE, and \(\beta\) and all the capacitance are very large
The value of DC current IE is
- (a)
1 mA
- (b)
2 mA
- (c)
5 mA
- (d)
10 mA