Analog Electronics - 1 - May 2012

Electronics & Telecomm. (Semester 3)

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. 1 (a) Design single stage R-C coupled CE audio frequency amplifier employing BC147B BJT to satisfy the following requirements. IAvI?100, S_ICO ?10, Load resistor RL=10k? and output voltage Vo=3volts.(15 marks) 1 (b) For the designed amplifier in part (a) determine; expected voltage gain, input impedance, output impedance and current supplied by source voltage V_CC {Use complete h-model for part(a) and (b) }(5 marks) 2 (a) Design single stage R-C coupled CS audio frequency amplifier employing JFET BFW-11 to satisfy the following requirements. |Av|?10, V_GSO=0.3Vp, RL=120? V_DD=20 vlts and output peak voltage V₀=4.5volts (12 marks) 2 (b) For the above designed circuit with source resistor ?R_S? unbypassed determine; voltage gain, input impedance, output impedance and output voltage for input voltage of 20 Vpp.(8 marks) 3 (a) For the circuit shown in Fig A. determine the following: 1. Voltage at collector terminal V_C 2. Voltage at base terminal V_B 3. Stability S_ICO 4. Voltage gain (10 marks) 3 (b) For the network of Fig B. With RD=2k2, RS=0.68k? and V_DD=20volts determine the following: 1. I_DQ and V_GSQ 2. V_DSQ and V_D 3. V_G and V_S 4. I_DQ if R_S is bypassed by capacitor C_S (10 marks)

Compare the following (Any Four)

4 (a) Output characteristics of CE and CS amplifier(5 marks) 4 (b) BJT series and BJT shunt voltage regulator (5 marks) 4 (c) D-MOSFET and E-MOSFET(5 marks) 4 (d) SCR and TRIAC (5 marks) 4 (e) LC and C-L-C filter (5 marks) 5 (a) Design a full wave rectifier dc supply using centre tapped transformer with two diodes to give dc output voltage at 300 volts to a variable resistive load. The load current expected is 75 ± 25 mA with ripple factor not to exceed 0.07. Use C-L-C filter.(12 marks) 5 (b) For the network of Fig C with RD=2K?, RG=10M?, and VDD=12volts.Determine the following: 1. I_DQ 2. V_DSQ (8 marks) 6 (a) Describe the operation of BJT series regulator and derive an expression for line regulation(Sv) and load regulation (Ro)(12 marks) 6 (b) Explain with the help of a circuit diagram the working of a UJT relaxation oscillator. (8 marks)

Explain the following (any four)

7 (a) Self thermal stability of JFET(5 marks) 7 (b) Utility of h- parameters(5 marks) 7 (c) Graphical determination of FET parameters (5 marks) 7 (d) Features of IGBT (5 marks) 7 (e) BJT as a Switch(5 marks) 7 (f) Power MOSFET (5 marks)