Analog Electronics 2 - Dec 2015

Electronics & Telecomm. (Semester 4)

TOTAL MARKS: 80
TOTAL TIME: 3 HOURS (1) Question 1 is compulsory.
(2) Attempt any three from the remaining questions.
(3) Assume data if required.
(4) Figures to the right indicate full marks.

Solve Any Four:

1 (a) In case of CE amplifier, why does the bandwidth of amplifier decrease with increase in gain? Support the answer with relevant mathematical equation.(5 marks) 1 (b) Instead of single Power Supply, why we use Dual power supply biasing for differential amplifier?(5 marks) 1 (c) Why Efficiency of class A power Amplifier is less than class B.(5 marks) 1 (d) What is the drawback of current mirror circuit using MOSFET? How it is overcome?(5 marks) 1 (e) Why we prefer series voltage Regulator over shunt voltage Regulator? Explain in detail.(5 marks) 2 (a) The Parameters of transistor are V_BE=07 V and β=100, V_A=0V, Determine
a) Q point of BJT
b) Time constant associated with C_C1 and C_C2
c) Lower cut-off frequency due to C_C1 and C_C2. (10 marks) 2 (b) For the PMOS CS amplifier, transistor parameters are V_TP=-2.V, Kp=1 mA/V², λ=0, Cgs=15 pf, Cgd=3pf
Determine
(a) Equivalent Miller capacitance
b) upper 3dB frequency (10 marks) 3 (a) For the given circuit, Determine
i) Differential mode gain Ad
ii) Common mode gain Ac
iii) CMRR
For BJT β=100 V_BE=0.7V, V_A=100V. (10 marks) 3 (b) Draw and explain the working of class A power amplifier (Transformer coupled). Derive the expression for efficiency.(10 marks) 4 (a) Draw and explain current mirror circuit using MOSFET, for the given circuit determine the value of l_ref and l₀ (10 marks) 4 (b) Draw the circuit diagram of Darlington pair using BJT, and derive the expression for Av, Ai, Zi and Zd.(10 marks) 5 (a) For the given circuit, derive the equation for voltage gain A_f and find V_o for given cor

Write short note on (Attempt any Four:)

6 (a) High pass and low pass filter using OPAMP(5 marks) 6 (b) Cascode amplifier using BJT(5 marks) 6 (c) Widlar current source using MOSFET.(5 marks) 6 (d) Transistor shunt voltage regulator.(5 marks) 6 (e) High frequency hybrid-π model of BJT.(5 marks)