JAWAHARLAL NEHRU TECHNOLOGICAL UNIVERSITY HYDERABAD B.Tech II Year ELECTRONIC CIRCUITS Previous Question Paper (September/October - 2023 - R16)

Define the Miller Effect Capacitance in amplifiers.

Define harmonic distortion in amplifiers and explain its implications in audio amplification.

Define the term “harmonic distortion” in amplifiers.

Explain the significance of the tank circuit in an LC oscillator?

Describe thermal runaway in transistors.

Explain why phase inversion is important in push-pull amplifiers.

Define a comparator and discuss its role in electronic circuits.

Describe the functioning of a low-pass RC circuit.

Define collector-emitter breakdown voltage (VCEO) for a transistor.

Explain the primary function of a Schmitt Trigger circuit.

Explain the key characteristics and operating principles of Common Emitter (CE) configuration amplifier and provide equations for voltage gain and input/output impedances.

What are the various types of distortion that can occur in amplifier circuits? Explain how distortion can be minimized or eliminated in amplifier design?

Compare and contrast the Common Emitter (CE), Common Base (CB), and Common Collector (CC) amplifiers in terms of voltage gain, input/output impedances, and applications.

Describe the low-frequency analysis of a Bipolar Junction Transistor (BJT) amplifier. Explain the role of coupling and bypass capacitors in shaping the low-frequency response.

Describe the operation of Wein Bridge oscillator and explain the frequency determination.

In an amplifier circuit, the open-loop voltage gain is 2000, and the feedback fraction is 0.02. Calculate the closed-loop voltage gain when negative feedback is applied.

With a neat circuit diagram, explain the principle of operation of a Colpitts oscillator and describe the role of each component in generating the oscillations.

In a feedback amplifier, the input impedance of the amplifier without feedback is 5 kΩ, and the feedback factor is 0.1. Calculate the input impedance of the feedback amplifier.

Explain the concept of complementary symmetry in push-pull amplifiers.

A transistor has a maximum power dissipation rating of 1 watt and a junction-to-ambient thermal resistance of 1000C/W. If the transistor's junction temperature is 1000C and the ambient temperature is 250C, calculate the maximum allowable power dissipation to avoid thermal runaway.

Discuss the operation of a Class-B power amplifier. Calculate the efficiency of a Class-B amplifier and explain why it is theoretically higher than that of Class A.

In a Class-B power amplifier, the collector current for each transistor is 1 A, and the supply voltage is 30 V. Calculate the power delivered to the load, the total power input, and the efficiency of the amplifier.

In a comparator circuit, the reference voltage is set at 1.5 V, and the input voltage is a triangular waveform that varies between 0 V and 3 V. Determine the points in time when the comparator switches its output state.

Explain how a diode clipper works. Present the transfer characteristics of a diode clipper and discuss its behavior when subjected to input signals exceeding the clipping levels.

With circuit diagrams and waveform illustrations, describe the operation of clamping circuits using diodes with square wave input signal.

In a transistor clipper circuit, a transistor is used to clip a sinusoidal input signal. The clipping levels are set at ±2 V. If the input voltage is a sinusoidal signal with a peak amplitude of 4 V, calculate the clipped output voltage.

Explain the concept of transistor switching times, including turn-on and turn-off times. Discuss factors that influence these times and their impact on switching applications.

Given a power supply voltage (VCC) of 12 V and a collector-emitter breakdown voltage (VCEO) of 30 V for a transistor, calculate the maximum allowable collector-emitter voltage to ensure the transistor's safe operation as a switch.

Describe the operation of bistable and monostable, multivibrators using transistors.

A Bipolar Junction Transistor (BJT) with turn-on and turn-off times of 50 ns and 30 ns, respectively, calculate the total switching time for the transistor when used in a switching circuit. Determine the maximum switching frequency achievable with this transistor.