IMPORTANT QUESTIONS FOR MID – 1

1. (a) Explain about the forward bias and reverse bias of PN junction.

    (b) Distinguish between Avalanche and Zener breakdown mechanisms.

2. (a) Give the relation between voltage and current of PN junction and explain each term in detail.

   (b) problem

3. (a) Derive the expression for transition capacitance of a diode.

    (b) Derive the expression for Diffusion capacitance of  a diode.

4. (a) What is a rectifier ? draw the circuit diagram of a HWR and explain its operation.

    (b)  Derive the expression for the ripple factor for a PI section filter when used with a FWR.

5. (a) Problem

    (b) Derive the expression for ripple factor, efficiency, average value, rms value, form factor and peak factor for a HWR.

6. (a) Define I_CBO and I_CEO.  Derive the following relations.

             (i)  1-α  = 1 / (1+ β)                (ii)  I_CEO = (1+ β ) I_CBO  

     (b) Explain the current components of a NPN transistor.

7. (a) Explain about CE transistor input and output characteristics interms of cutoff, active and saturation regions.

    (b) Compare CB, CC and CE configurations.

8. (a) Explain the need of biasing a transistor.

    (b) Explain the concept of dc operating point with the help of dc load line with neat sketches.