1. Write the significance of lock range of a PLLMay/June 20132. What is the function of a voltage regulator?May/June 2013A voltage regulator is an electronic circuit that provides a stable dc voltageIndependent of the load current, temperature, and ac line voltage variations.3. What is the principle of SMPS?May/june 20134. Why VCO is called voltage to frequency converter? Nov/Dec 20125. What is an isolation amplifier? Nov/Dec 2012,2011An isolation amplifier is an amplifier that offers electrical isolation between its input and output terminals.

6. Name the various protection circuits used for voltage regulators.Nov/Dec 20127. In what way VCO is different from other oscillatorsMay/June 20128. Mention any two applications of 555 timer in monostable mode.May/June 20129. Why do switching regulators have better efficiency then the series regulators?May/June 201210. What is an OptocouplerMay/June 2012, Nov/Dec 200911. What are the advantages of IC voltage regulators?Nov/Dec 2009 low cost high reliability reduction in size excellent performance12. Give the drawbacks of linear regulators:Nov/Dec 2011 The input step down transformer is bulky and expensive because of low line frequency. Because of low line frequency,large values of filter capacitors are required to decrease the ripple. Efficiency is reduced due to the continous power dissipation by the transistor as it operates in the linear region.13. Define capture range of PLL.Nov/Dec 2011The range of frequencies over which the PLL can acquire lock with the input signal iscalled as capture range.14. List the applications of NE565. Nov/Dec 201015. Draw the relation between the capture range and lock range relationship in a PLL.16. How will you increase the output of a general purpose op-amp?17. Using LM380 draw the circuit for audio power amplifier18. Draw the pin diagram of IC 555 timer.Apr/May 201019. Mention any two application of multiplier IC.20. List the important parts of regulated power supply.21. What are the advantages of switch mode power supplies?22. What is the need for switching regulators?Nov/Dec 200923. Enlist the important features of 555 timer circuit.24. Determine the output pulse width of the monostable amplifier using 555 timer if R = 10K and C = 0.01F.25. List the characteristics of OptocouplerApr/May 200826. Mention the advantages of an isolation amplifierNov/Dec 200827. What is an Optocoupler? Where is it used?Nov/Dec 200828. Draw the block diagram of PLL as frequency multiplier.Nov/Dec 200829. What is the function of reset in 555 timer?Apr/May 2007, Nov/Dec 200630. Define PULL time of PLL.Nov/Dec 2006