Electronic Circuits and Devices Question Paper of 3rd Semester ECE16 Download Previous Years Question Paper 4

Roll No.

Total No. of Questions : 091

B.Tech. (Sem. – 3rd)

ELECTRONICS DEVICES & CIRCUITS

SUBJECT CODE : EC - 201

Paper ID : [2126]

Time : 03 Hours

Instruction to Candidates:

1) Section - A is Compulsory.

2) Attempt any Four questions from Section - B.

3) Attempt any Two questions from Section - C.

Section - A

Ql)

a)     Draw the Ideal characteristics of the Diode.

b)    With the characteristic curves & write briefly about working of photo diode.

c)     Write the advantages of MOSFET.

d)    In a fixed bias circuit

R_B =150kΩ, R_C. = 2kΩ, V_CC = l2V,Transistor is silicon with B=100

then find ‘i_B’.

e)     Write the advantages of class 'AB' amplifier.

f)      In what type of applications tuned coupling are used. ..

g)     What is meant by feed back? What type of feed back is used in oscillator.

h)    write the characteristics of current shunt feedback amplifier.

i)       Draw and explain the general tank circuit of LC oscillator.

j)       Expl4rn Thermal Runway.

section-B

 Q2) (a) In a diode how the carrier is developed.

(b) Draw the equivalent circuit of Junction Diode

.

Q3) Draw the hybrid model of a low frequency small signal voltage Amplifier.

Q4) Draw and explain the V-I characteristics of JFET.

Q5) A silicon transistor uses potential divider method of Biasing V.. = 12V

R₁ = 10 kΩ, R₂ = 5 kΩ, R₁ = 1 kΩ and R_E = 3 kΩ. Determine the operating point using The venin’s theorem.

 Q6) For class A, CE, amplifier circuit shown in Figure (V_CE)r=10V and

(I_C ), =500mA. If the output current varies by +250mA when an input signal  is applied at the Base, compute the collector efficiency and over all efficiency.

Section - C

Q7) (a) Why the transistor circuit requires stabilization?

(b) Derive the stability factor(s) for voltage division method.

Q8) (a) Draw the circuit of a class 'B' push-pull amplifier and explain its operation

(b) Derive the voltage distortion in push-pull amplifier.

Q9 Derive the expression for the frequency of oscillations and condition for sustain oscillations in a Colpitt’s oscillator.