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PLEASE MATCH YOUR ASSIGNMENT QUESTIONS ACCORDING TO YOUR SESSION
IGNOU MPH-05 (January 2026 – December 2026) Assignment Questions
PART A
1. a) Describe various electron-hole pair generation processes in semiconductor.
b) Explain the complete switching ON and OFF cycle of a power diode with the help of appropriate diagram. What are forward and reverse recovery times of a power diode?
c) How can the efficiency of a solar cell be increased? How is the optimum bandgap chosen for the solar cell material?
2. a) Describe the difference between the construction and operation of enhancement mode and depletion mode MOSFET.
b) What are the causes of non-ideal characteristics of a p-n junction diode?
3. a) Define intrinsic stand-off ratio of a UJT. Draw and explain the I-V characteristic of UJT.
b) In single ended input – single ended output configuration of a differential amplifier, the input voltage is 10 mV. If the collector resistors RC1= RC2= 47k, emitter resistor RE= 39 k and supply voltage is 12V, calculate the differential gain and output voltage of the circuit. Assume that the you are using Si transistors.
4 a) Draw the lead-lag network of Wien bridge oscillator and obtain the expression for its oscillation frequency and required amplifier gain using time domain analysis.
b) Draw and explain the equivalent LCR resonant circuit of an oscillating crystal. A crystal has C = 0.04 pF, L = 1 H and R= 2 k. Calculate its series resonant frequency. What is the effect of the crystal thickness on its frequency?
c) Describe the construction of Gunn diode. Explain with the help of E-k diagram the origin of negative resistance region in its I-V characteristics.
PART B
5. a) Design and draw the circuit using op amps to solve the following simultaneous equations:
3x + 4y = 12
x – 4y = 20
b) Design and draw the circuit of a non-inverting Schmitt trigger using op-amp with hysteresis of 40% of VSAT.
6. a) What are CMRR and slew rate of an op-amp? Explain with examples their effects on the performance of an op-amp.
b) Explain the working of an op-amp based full wave precision rectifier with the help of appropriate circuit diagram. What are its advantages over a simple diode rectifier?
c) Draw the circuit of antilogarithmic amplifier using an op-amp and obtain the expression for its output voltage.
7. a) Explain the working of a shunt regulator using zener diode. What are the limitations of this circuit due to the non-idealities of the zener diode?
b) Explain the terms lock range and capture range with reference to PLL. Why is the capture range smaller than the lock range?
8. a) Describe the software techniques used for improving the signal-to-noise ratio of an electronic system.
b) Output of a 4-bit DAC for digital input of 1001 is 4.5 V. Determine its step size and percentage resolution. What will be the output for digital input of 1110?
c) Write an Assembly language program for microcontroller 8051 to compute the average of 6 bytes data stored from RAM location 45H and store the result at RAM location 30H.
