Question

1. Explain the Barkhausen criterion for sustained oscillation. How is it satisfied in the phase-shift oscillator circuit?
2. Design a zener regulated power supply to give 9.1V DC output with maximum load current of 50 mA. Assume that the minimum IZ required for proper functioning of zener diode is 5 mA, and the unregulated DC input is 12V. Indicate the value of RS and power ratings of zener diode and RS.
3. a) Which parameters of an op-amp become significant for a fast varying ultra low input voltage signal? What should be the values of these parameters for a triangular wave signal of ±5 mV peak to peak with 50 MHz frequency given to a unity gain op-amp amplifier?
b) Design and draw the circuit using op-amp to provide the output voltage obeying following relation of input voltages:
Vo=-10V1 - 0.3 dV2/dt -2V3
7. a) Design and draw a voltage comparator circuit using op-amp IC 741 to give +VSat at the output if the input voltage is less than -3V and -VSat for input more than -3V. b) Design and draw the circuit of a voltage regulator using LM 317 to provide an adjustable voltage between 6 to 12V.
8. a) Divide 11618 by 318. Express the obtained result in decimal number. b) Draw a half adder circuit using only NAND gates.
9. a) Explain the working of J-K flip flop. How does it differ from R-S flip flop?
b) With the help of a diagram explain the construction of a cathode ray tube. What measurements can you do by using of a CRO?

Answer 1

I don't know..... Mm