Course Code:EC202
Analog Electronic Circuits
Duration: 3 Hrs Maximum Marks: 100
Note:
1. Part-A is mandatory.
2. Answer any five full questions from Part-B choosing at least one from each module.
PART-A
Q.No. Question BL CO PO Marks
List any two advantages of doping in semiconductors.
1 L1 1 1 2
List any two advantages of Schottky barrier diode.
2 L1 1 1 2
3 Mention any four applications of bipolar junction transistor. L1 1 1 2
4 What is base width modulation in BJT? L1 2 1 2
5 What you mean by biasing ?Also mention the need for biasing L1 2 1 2
6 State the drawback of zero crossing detector. L1 3 1 2
Give at least two applications for the PLL. 2
7 L1 3 1
Design a monostable 555 timer to produce an output pulse of 2
8 L1 3 1
10msee wide .
Explain the purpose of solder mask and silkscreen. 2
9 L1 4 1
1
What is DRC,DFM? Why these tests are done? 2
10 L1 4 1
PART-B
Q.No. Question BL CO PO Marks
Module-1
1 a) Explain the operation of CMOS inverter. L2 1 1 6
b) A silicon at T = 300 K doped with phosphorous and boron at a L2 1 1,2 3
concentration of Nd = 1016cm-3 and Na = 5 x 1016cm-3 respectively.
Calculate the thermal equilibrium electron and hole concentrations.
Assume ni = 1.5 x 1010cm-3 .
Using a piecewise linear model, determine the diode voltage and diode
current in the circuit shown in Figure 1. Also determine the power
dissipated in the diode. Assume piecewise linaer diode parameters of
Vγ = 0.6V and rf = 10Ω.
c) L3 1 1,2,3 7
Figure1
OR
2 With a neat constructional diagram, explain the working principle of L2 7
a) 1 1
Schottky barrier diode. Also, write the applications of Schottky barrier
diode.
Calculate the current in an n-channel MOSFET. Consider an L2 3
n-channel enhancement-mode MOSFET with the following para
b) meters: VTN = 0.4V, W = 20μm, L = 0.8μm,μn = 650cm2/V–s, tox 1 1,2,3
= 200Å, and Cox = (3.9)(8.85 × 10−14) F/cm. Determine the
current when the transistor is biased in the saturation region for
VGS = 0.8V.
2
Analyze and determine the DC and AC quantities in the circuit shown L3 6
in Figure 2. Assume the circuit and diode parameters of Vps = 5V, R =
5KΩ, Vγ = 0.6V, and vi = 0.1sinωt(V).
c) 1 1,2,3
Figure 2
Module-2
3 a) Analyze and design the DC analysis of npn transistor in L2 2 1,2 8
common-emitter configuration. Assume the transistor is biased in
forward-active mode. Also write its DC equivalent circuit.
Analyze the common-emitter circuit with a pnp transistor for the
circuit shown in Figure 3. Calculate the IB, IC, IE and Rc such
that VEC = V+/2 Assume the transistor parameters are VEB(on) =
0.6V and β = 100. Also indicate the calculated values in the
circuit diagram.
b) L3 2 1,2 8
Figure 3
OR
a) With neat circuit diagrams and relevant equations, explain the L2 2 1 8
transistor behaves as a switch and digital logic.
3
For the circuit shown in Figure 8, let VCC = 3.3 V, RE = 500 , RC =4k
,R1 =85k ,R2 =35k ,and β =150. (a) Determine RTh and VTh. (b) Find
IBQ, ICQ, and VCEQ.
b) L3 2 1,2,3 8
Module-3
5 Draw and explain the working of differentiator using op amp, Obtain
a) expressions for the cut off frequencies 𝑓𝑎 𝑎𝑛𝑑 𝑓𝑏. L2 3 1 8
Explain the working of a first order active high pass filter with circuit
and frequency response. Design a first order high pass filter for 𝑓𝐿 =
b) 5𝐾𝐻𝑧, pass band gain = 4. Assume 𝐶 = 0.01 𝜇𝐹. Draw the circuit L2 3 1,2,3 8
diagram and its frequency response. &
L3
OR
6 a) Define the following (i)Common mode gain (ii)Differential mode gain L1 3 1 3M
(iii) input and output impedance
b) With a neat diagram explain the op amp based difference amplifier L2 3 1 7M
circuit with relevant expressions for the output.
Design an averaging amplifier in inverting mode. Assume the input
c) voltages are 𝑉𝑎 = 1𝑉, 𝑉𝑏 = 2𝑉, 𝑉𝑐 = 3𝑉. Draw the circuit diagram. L3 3 1,2,3 6M
Module-4
7 Explain the operation of a successive approximation analog to digital
a) converter and mention it’s advantages. L2 3 1 8
4
Design an astable multivibrator using 555 IC timer with
(i) fo = 1 kHz and D = 40%
b) (ii) fo = 2 kHz and D = 50% L3 3 1,2,3 8
(iii) fo = 1 kHz and D = 70%
Assume c = 0.01uF for all cases.
OR
8 What is R-2R network type DAC? Explain with relevant expressions L2
a) & 3 1 8
L2
Explain the operation of 555 timer as a Monostable multivibrator with L2
relevant expressions. Also write it’s applications.
b) & 3 1 8
L2
Module-5
9 a) Explain different types of PCB, based on layers with a neat diagram. L2 4 1 8
b) List and explain all the mechanical layers of PCB. L2 4 1 8
OR
Explain in depth all the key elements of PCB.
10 a) L2 4 1 4M
Explain two types of components used for making PCB?
b) L2 4 1 4M
c) Explain in brief different layers used in two layer PCB? L2 4 1 8M
5
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