Analog Electronics — DU B.Sc. (Prog.) Physical Science courses pertaining to Electronics Previous Year Question Papers

(Under NEP-UGCF 2022) : IV – (DSE Paper) Attempt four questions in all. 1. (a) Describe the working principle of the Solar Cell. (3) (b) What is the importance of the Q-point in transistor circuits like amplifier? (3) (c) Draw and explain the I-V characteristics of a p-n junction diode in forward and reverse bias. (3) (d) Discuss the characteristics of an ideal OP-Amp. (3) (e) Distinguish between half-wave and full-wave rectifiers. (3) (f) Derive the current gain of an op-amp in a non-inverting configuration. (3) 2. (a) Explain the structure and working of n-p-n or p-n-p transistors. (8) (b) What is the ripple factor and rectification efficiency of a full-wave rectifier? (7) 3. (a) Describe the working of the Zener diode as a voltage regulator with a neat circuit diagram. (8) (b) Discuss the input and output characteristics of a transistor in CB configurations. (7) 4. (a) Define CMRR slew rate with respect to the Op-Amp. (b) (c) (6) Describe the working of a CB amplifier using the h-parameter model and derive the expression for voltage gain. (6) Discuss the Op-Amp as both an integrator and a comparator. (3) 5. (a) Derive the expression for the frequency of a Colpitt oscillator. (7) (b) The operating point is selected such that IC = 5 mA, VCE = 5 V, RC = 2 K and VCC = 20 V. Find R1, R2 and RE. Current through R1 is 10 times the base current. Assume  = 50 and VBE = 0.7 V. (5) (c) Explain the effect of a change in  on the characteristic curve of BJT.