Download PTU B.Tech 2021 Jan ECE 3rd Sem 78746 Electronic Devices Question Paper

Download PTU (Punjab Technical University) B.Tech (Bachelor of Technology) / BE (Bachelor of Engineering) 2021 January ECE 3rd Sem 78746 Electronic Devices Previous Question Paper

Roll No.
Total No. of Pages : 02
Total No. of Questions : 18
B.Tech. (ECE) (Sem.?3)
ELECTRONIC DEVICES
Subject Code : UC-BTEC-301-19
M.Code : 78746
Time : 3 Hrs. Max. Marks : 60
INST RUCT IONS T O CANDIDAT ES :
1 .
SECT ION-A is COMPULSORY cons is ting of TEN questions carrying TWO marks
each.
2 .
SECT ION-B c ontains F IVE questions c arrying FIVE marks eac h and s tud ents
have to atte mpt any FOUR q ues tions.
3 .
SECT ION-C contains THREE questions carrying T EN marks e ach and s tudents
have to atte mpt any T WO questio ns.
SECTION-A
Write briefly :
1)
How can you classify solids on the basis of conductivity? Give examples also.
2)
Give the Energy band diagrams of Intrinsic and Extrinsic Semiconductors.
3)
Differentiate between Drift current and Diffusion current in a semiconductor.
4)
What do you understand by :
i) Depletion region and
ii) Potential barrier - in a semiconductor.
5)
What is Ebers-Moll model in Transistors?
6)
Define MOSFET. Give its types.
7)
What is the purpose of Sputtering in Fabrication process of ICs or devices?
8)
Give the circuit symbols for Zener diode, Tunnel diode, Varactor diode and a Transistor.
Label them properly.
9)
Draw the Input and Output V-I characteristics of a bipolar junction transistor. Label the
characteristics wherever required.
10) What is the significance of Etching in fabrication processes of Electronics devices? Name
some commonly used etchants.
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SECTION-B
11) Discuss the behavior of pn-junction diode when forward biased as well as reverse biased
giving suitable neat diagrams.
12) Explain the construction and working of a MOSFET. Give its V-I characteristics.
13) What are the three important configurations in which the transistor can be connected?
Discuss any one of them.
14) Define: Diffusion and Ion-Implantation. What are the various types of Ion-implantation
techniques that are commonly used in fab line?
15) A full-wave rectifier uses two diodes, the internal resistance of each diode may be
assumed constant at 20. The transformer r.m.s. secondary voltage from centre tap to
each end of secondary is 50V and load resistance is 980V. Find:
i) The mean load current (Idc)
ii) The r.m.s. value of load current
SECTION-C
16) Draw and explain Half-wave and full-wave (center-tapped & bridge) rectifiers with
suitable circuit diagrams. Which one is more preferable and why?
17) Write short notes on :
i) Light Emitting Diode (LED)
ii) Schottky Diode.
18) List and explain the various important fabrication processes used for the fabrication of
BJTs/MOSFETs.
NOTE : Disclosure of Identity by writing Mobile No. or Making of passing request on
any page of Answer Sheet will lead to UMC against the Student.
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