JNTU, B.Tech,I-Semester BASIC ELECTRONICS, November 2008
(Mechanical Engineering, Production Engineering and Automobile Engineering)
1. (a) Draw the atomic structure for P and N type semiconductors. Explain about minority and majority carriers.
(b) Draw Bridge rectifier circuit and explain the working of it. What are the advantages of it over the full wave rectifier with centre tapped transformer?
2. (a) What is “Early effect”phenomenon in a transistor and explain its consequences.
(b) Draw and explain the input and output characteristics of n-p-n transistor in
C- B configuration.
3. (a) State the merits and demerits of Negative feedback in amplifiers.
(b) What is an oscillator? Explain why positive feedback is necessary to produce oscillations.
4. (a) Classify the timers according to the function and the technique used to achieve
the industrial timing.
(b) List the electronic welding controls used in resistance welding.
5. (a) Explain the principle of dielectric heating.
(b) Explain the application of dielectric heating for
i. Pre-heating of plastic preforms and
ii. Food processing.
6. (a) Explain the working and construction of a CRT with neat sketch. Give the detailed description of all parts in a CRT.
(b) What is a time base? State the need for time base in CRO.
7. (a) What is a Microprocessor?
(b) Explain about various addressing modes of microprocessor with suitable examples.
8. (a) Derive an expression for an output voltage of inverted R-2R ladder DAC.
(b) The digital input for a 4-bit DAC is 0110. Calculate its final output voltage.