Bangalore University 2005 Diploma Instrumentation & Control Engineering SEMICONDUCTOR DEVICES ( Code EP, EC & IC) - Question Paper

Second Semester Diploma (Annual) Examination, 2005
E & C Board
SEMICONDUCTOR DEVICES
(Course Code EP, EC & IC)

Time : three Hours Max. Marks : 100

Note : i) ques. No. one of part – I is compulsory
ii) ans any 6 full ques. choosing 2 ques. every from Sections-II, III and IV.

part - I

1.a) Fill in the blanks with improper word / words:

i) A semiconductor has ………….. temperature co-efficient of resistance.

ii) Varactor diode is always ……………. biased.

iii) A tunnel diode is a …………….. PN junction diode.

iv) The noise level in JFET is ............ as compared to ordinary transistor.

v) CMOS has a ............ power consumption.



b) Write short notes on burglar alarm and smoke detector.



part - II

2.a) What is PN Junction? discuss the formation of depletion layer in a PN Junction?

b) elaborate donor and acceptor impurities? discuss with examples.

c) What is barrier potential? provide its value for germanium and silicon.

3.a) With the help of suitable diagram, discuss the V-I characteristics of PN Junction diode.

b) elaborate an ideal diode and a real diode? discuss.

c) List the applications of a Junction diode.

4.a) Explain the output characteristics of a common base NPN transistor. Indicate the active, cut-off and saturation regions.

b) If a transistor has Ic = 4.8 mA, Ib = 100 mA and IE = 4.9 mA, compute the values of a and b.

c) Write a short note on Heat sink.

part - III

5.a) discuss the transfer and draw characteristics of a JFET.

b) describe the subsequent terms for JFET

i) Drain Resistance (rd)

ii) Transconductance (gm)

iii) Amplification factor m

c)Explain the working of a transistor as a switch.


6. a) discuss the construction and operation of enhancement kind MOSFET.

b) Compare JFET with MOSFET.

c) discuss the advantages of N-channel MOSFET over P-channel.

7.a)Explain the V-I characteristics of UJT and indicate how it exhibits
negative resistance property.

b) List the applications of UJT.

c) discuss the working of CMOS inverter.

part - IV

8.a)Explain the construction and working principle of a Tunnel diode.

b)Explain Opto coupler.

c)List the application of a PIN diode

9.a)Explain the construction, working principle and characteristics of a photo transistor.

b) discuss the working of a LASER.

c) List the applications of GUNN diode.

10.a) discuss the processes involved in the fabrication of monolithic ICs.

b) describe SSI, MSI, LSI and VLSI.

c) Write a short note on IMPATT diode.

* * * * * *

Earning:   Approval pending.