Jawaharlal Nehru Technological University Hyderabad 2005 B.E Computer Science ELECTRONIC DEVICES & CIRCUITS I BTechRegular s, set 2 - Question Paper
Tuesday, 18 June 2013 05:20Web
Code No: RR10205 Set No.2
I B. Tech. Regular Examinations, June 2005
ELECTRONIC DEVICES & CIRCUITS
( Common to Electrical & Electronic Engineering, Electronics &
Communication Engineering, Computer Science & Engineering, Electronics
& Instrumentation Engineering, BioMedical
Engineering, info
Technology, Electronics & Control Engineering, Computer Science &
Systems Engineering, Electronics & Telematics, Electronics & Computer
Engineering and Instrumentation & Control Engineering)
Time: three hours Max Marks: 80
ans any 5 ques.
All ques. carry equal marks
? ? ? ? ?
1. (a) An electron is moving perpendicular to magnetic field ‘B’. Derive the
expression for radius ‘R’ of the trajectory and period of rotation T
(b) Derive the expression for the electro magnetic deflection sensitivity in the case
of the CRT[8+8]
2. (a) discuss why pn
junction constant potential cannot be measured by placing a
voltmeter across the diode terminal.
(b) With reference to the PN
junction diode.
i. Distinguish ranging from drif T current and diffusion current.
ii. Distinguish ranging from diffusion capacitance and transition capacitance.[8+8]
3. (a) Compare half wave, Full wave and Bridge rectifier.
(b) What is the necessity of having filter in power supply? find the ripple factor
of a full wave rectifier with shunt capacitor filter.[8+8]
4. (a) discuss the input and output characteristics of CE configuration of a transistor
and indicate different regions.
(b) Prove that for a CE transistor in active region IC = b IB + (1 + b )Ico.[8+8]
5. (a) Compare JFET and MOSFET with respect to different features.
(b) Draw the biasing circuit suitable for JFET and if the JFET is changed by a
MOSFET for what mode of operation it is valid and discuss about the function
of every component used in the circuit.[8+8]
6. (a) elaborate the compensation techniques used for VBE and ICO. discuss with
the help of suitable circuits.
(b) Draw the hParameters
equivalent circuit of CC,CE configuration and what
are the typical values of hParameters
for a transistor in CE and CB configuration.[8+8]
7. (a) Briefly explain about the effect of feedback on amplifier Bandwidth.
(b) Draw the frequency response of an amplifier with and without feedback and
show the bandwidth for every case and how these 2 curves are related to
gain bandwidth product.
(c) We have an amplifier of 60db gain. It has an output impendence Zo = 10k.
it is needed to replace its output impendence to 500 by applying negative
feedback. compute the value of the feedback factor Also obtain the percentage
change in the over all gain, for 10% change in the gain of the internal amplifiers.[8+8+8]
8. (a) Draw the circuit diagram of a RC phases shift oscillator using BJT. Derive
the expression for frequency of oscillators.
(b) Classify various kind of oscillators based on frequency range.
(c) Why RC oscillators are not suitable for high frequency applications.[8+8+8]
Earning: Approval pending. |