analog electronic circuits unit 1 vtu

8/13/2019 Analog Electronic Circuits unit 1 vtu

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ANALOG ELECTRONIC CIRCUITS

(VTU)

3rdSem EC/EE/TC

UNIT 1:

Diode Circuits: Diode Resistance, Diode equivalent circuits, Transition and diffusion

capacitance, Reverse recovery time, Load line analysis, Rectifiers, Clippers and clampers.

(Chapter 1.6 to 1.14, 2.1 to 2.9)

6 Hours

TEXT BOOK:

1. Electronic Devices and Circuit Theory, Robert L. Boylestad and Louis Nashelsky,

PHI/Pearson Education. 9TH Edition.

REFERENCE BOOKS:

1. Integrated Electronics, Jacob Millman & Christos C. Halkias, Tata - McGraw Hill, 2nd

Edition, 2010

2. Electronic Devices and Circuits,David A. Bell, PHI, 4thEdition 2004

3. Analog Electronics Circuits: A Simplified Approach, U.B. Mahadevaswamy,

Pearson/Saguine, 2007.

BY:

RAGHUDATHESH G PAsst Prof

ECE Dept, GMIT

Davangere 577004

Cell: +917411459249

DIODE CIRCUITS RAGHUDATHESH G P Asst Prof

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Diode Circuits

Diode Basics:

A diode is a specialized electronic component with two electrodes called the anodeand

the cathode.

Most diodes are made with semiconductor materials such as silicon, germanium, or

selenium. Some diodes are comprised of metal electrodes in a chamber evacuated or

filled with a pure elemental gas at low pressure.

Diodes can be used as rectifiers, signal limiters, voltage regulators, switches, signal

modulators, signal mixers, signal demodulators, and oscillators.

The fundamental propertyof a diode is its tendency to conduct electriccurrent in only

one direction.

When the cathode is negatively charged relative tothe anode at a voltage greater than acertain minimum calledforward breakover, then current flows through the diode.

This is a simplistic view, but is true for diodes operating as rectifiers, switches, and

limiters.

The forward breakover voltage is approximately six tenths of a volt (0.6 V) for silicon

devices, 0.3 V for germanium devices, and 1 V for selenium devices.

When an analog signal passes through a diode operating at or near its forward breakover

point, the signal waveform is distorted.

This nonlinearityallows for modulation, demodulation, and signal mixing.

Semiconductor diodes can be designed to produce direct current (DC) when visible light,

infrared transmission (IR), or ultraviolet (UV) energy strikes them. These diodes are

known as photovoltaic cells and are the basis for solar electric energy systems and

photosensors.

Another form of diode, commonly used in electronic and computer equipment, emits

visible light or IR energy when current passes through it. Such a device is the familiar

light-emitting diode(LED).


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http://searchcio-midmarket.techtarget.com/definition/semiconductorhttp://searchtelecom.techtarget.com/definition/switchhttp://searchcio-midmarket.techtarget.com/definition/currenthttp://searchcio-midmarket.techtarget.com/definition/currenthttp://searchtelecom.techtarget.com/definition/switchhttp://searchcio-midmarket.techtarget.com/definition/semiconductor


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Various ClipperConfigurations



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Various ClamperConfigurations

(CHEET SHEET)



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Question Bank

1. What do you understand by transient and diffusion Capacitance?2. Draw a double diode clipper, which limits at two independent levels and explain its

operation.

3. Explain different resistance levels associated with diode.4. Descried diode equivalent model.5. Explain reverse recovery time associated with the diode.6. What is the difference between positive and negative clippers? Explain with the help of

output waveform.

7. With the help of circuit diagram, describe the operation of clipper that can clip at twoindependent levels. Choose a suitable waveform for clipper description. Explain how

the two clipping level can be controlled independently

8.

Sketch the circuit of a positive series clipper showing the input and output waveforms,Briefly explain its operation.

9. Distinguish between clipping and clamping circuits with suitable circuits with suitablediagram and supporting input and output waveforms.

10.Distinguish between clipping and clamping circuits with suitable circuits with suitablediagram and supporting input and output waveforms.

11.Write the difference between clipping and clamping circuits.12.What is the purpose of a clamping circuit? Explain the working of a diode clamper. How

clamping to a dc level is achieved.

13.How does an ideal diode behave as an amplitude limiter?14.Briefly explain how a diode capacitor circuit serves as a dc restorer.15.Draw and explain the working of positive clamper16.Draw the circuit of negative clipper with input and output waveforms.17.Draw a simple clamping circuit and explain its working?18.Draw the circuit diagram of half-wave rectifier. Explain its working. What is the

frequency of ripple in its output?

19.Draw the circuit diagram of full-wave rectifiers (a) with centre-tap connection, and b)bridge connection. Explain their working. What is the peak-inverse voltage of a diode in

each case?

20.What are the advantages of a bridge rectifier as compared to a full-wave centre-tappedrectifier

21.What is efficiency of rectification? Compare half-wave and full-wave rectifiers from thepoint of view of rectification efficiency.

22.Define (i) a ripple factor, (ii) rectification efficiency, and (iii) transformer utilizationfactor for a rectifier.


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23.Define Transformer Utilization factor.24.Define the terms P.I.V and regulation as applied to rectifiers25.Explain the validity of the piecewise linear approximation of the diode model26.Draw the circuit diagram of a bridge rectifier. Plot its input and output waveforms.27.

Explain reverse recovery time associated with diode.

28.Differentiate between half, full and bridge rectifier.29.A full-wave rectifier is fed by a 24 \lac (rated) centre-tapped transformer. What is the d.c.

output voltage of the circuit. If the rectifier is connected to a load resistance of 2.2 k

load, what is the d.c. value of load current.

30.A full-wave rectifier uses two diodes; the forward resistance of each diode is 20. Thetransformer r.m.s. secondary voltage from centre-tapped to each end of the secondary is

50 V and the load resistance is 980 . Determine (a) the average val ue of load current,

and (b) the r.m.s. value of load current.

31.A 50 Hz transformer having 50 V r.m.s. on each side of the centre-tap supplies a full-wave rectifier circuit. The circuit load is 150 Q with a shunt capacitor filter of 1000 F.

Find the ripple factor.


analog electronic circuits unit 1 vtu

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