EDC LAB VIVA Questions with Answers :-
EDC VIVA Questions and Answers :-
[MUST ASKING QUESTIONS IN VIVA & EXAM]
41.Why are the coupling capacitors required?
To filter the Dc term from the Input signal , Collector output in amplifiers.
42.What is meant by thermal stabilization?
Maintain a constant operating point when temperature varies
43.Explain why reversal of phase occurs in a BJT CE Amplifier.
As Base voltage increases, base current increases, then collector current increases so voltage drop across Rc increases so out put voltage decreses.
44.What happens if an amplifier is biased at cutoff or at saturation?
In cutoff region Ic is 0, in saturation region Vce is almost Zero.
45.What is the significance of the bandwidth of an amplifier?
Bandwidth specifies the input signal frequency range that can be applied to amplifier to get maximum gain.
46.What is meant by Gain-Bandwidth Product? What is its significance?
The name itself expressing it is the product of gain of a device and its bandwidth. For any system (circuit) gain bandwidth product is constant, if gain increases bandwidth decreases vice versa.
47.What are the advantages of using a FET instead of a BJT?
FET has high input impedance, lower noise, low to medium gain,
48.What are the specifications of the SCR ?
gate trigger voltage, gate trigger current, holding current, on-state voltage, peak gate power dissipation.
49.Can we interchange the source and drain terminals in a FET circuit? Can we do the same with the emitter and collector terminals of a BJT circuit?
We can interchange drain and source but we cannot change emitter and collector because emitter and collectors dimensions and doping concentration is different
50.What is a MOSFET? How is it different from a JFET? What are its typical applications?
Metal oxide semiconductor can be operated in both depletion and enhancement modes, but Junction field effect Transistor can be operated in depletion mode only.