electronics lab manual

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LABORATORY MANUAL

ECE 132

BASIC ELECTRICAL AND ELECTRONICSENGINEERING LABORATORY

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LIST OF PRACTICALS

S.No. Title of experiment Page No.

1 AC circuits (Familiarization of resistors, capacitor and inductor) 03-13

2 House wiring (Wiring of different lamp control, stair casing circuits,assembly and wiring of fluorescent tube light) 14-16

3Distribution board (To make a single phase main distortion board withfive outgoing circuits for light load and fan load including main switchand fuses)

17-17

4PN Junction Diode (To study the VI characteristics of PN junction diodeandZener diode)

18-20

5 voltage regulator (Implementation of voltage regulator using Zenerdiode) 21-23

6 Rectifier (Implementation of half wave and full rectifier using diodesand thyristors on bread board and also on Pspice) 24-26

7 Resonance (To verify series and parallel resonance in AC circuits) 27-30

8Bipolar junction transistor (To study the VI characteristics of Bipolarjunctiontransistor)

31-36

9 DC Motor (Direction control of DC motor) 37-37

10 Thyristor (Study the VI characteristics of a Thyristor) 38-39

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EXPERIMENT NO. 1

AC circuits:Familiarization of resistors, capacitor and inductor

Familiarization of resistors:

Learning Objectives:

Explain the function of and unit of resistors Measure the value of a resistor Measure the tolerance of a resistor Explain the types of resistors

Resistors:

Oppose the flow of current (electrons) Resistance is measured in Ohm 1000 Ohm resistor is shown as 1 k Ohm and 1000 K Ohm resistor is shown as 1 M Ohm

Types of resistors:

Fixed Variable

Fixed resistors:

Carbon film, metal film, wire wound resistors (value of resistor is specified and cannot be changed)

Variable resistors:

Semi fixed completely variable, potentiometer (can be changed by rotating the wiper)

Reading value of fixed resistors:

Resistors are color coded as they are too small for the value to be written on them.There are 4 or 5 bands of color. Value of a resistor is decoded from these bands of color.

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EXPERIMENT NO. 1





Resistors:


Types of resistors:

Fixed Variable

Fixed resistors:


Variable resistors:




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EXPERIMENT NO. 1





Resistors:


Types of resistors:

Fixed Variable

Fixed resistors:


Variable resistors:




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Reading value: Step 1:

If your resistor has four color bands, turn the resistor so that the gold or silver band is on the right handside or the end with more bands should point left.

Step 2:

The first band is now on the left hand side. This represents the first digit. Based on the color make a noteof the digit. In this case- 4 band its ‘5’ and for 5 band its ‘2’.

Step 3:

The second band represents the second digit. The colors represents the same numbers as did the firstdigit. In this case- 4 band its ‘6’ and for 5 band its ‘3’.Step 4:

The third band divulgues how many zeros to add/divide to the first two numbers – for a 4 band resistor.In this case- 4 band its ‘4’ zeros to be added. So value is 560K.

Step 5:

The third band denotes the 3rd digit – for a 5 band resistor. In this case -5 band its ‘7’. So the value of the5 band resistor is 237 Ohms as its multiplier digit is ‘0’.

Tolerance:

The last band denotes the tolerance. So the value of the 4 band resistor it is +/- 1%.

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Step 2:


Step 3:



Step 5:


Tolerance:


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Step 2:


Step 3:



Step 5:


Tolerance:


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Tolerance of a resistor is also an important property to consider A 100 Ohm resistor with a 10 % tolerance can mean its value can be any fixed value between 90

to 110 Ohms A 120 Ohm resistor with a 10 % tolerance can mean its value can be any fixed value between 108

and 132 Ohms So there is some overlap between 100 Ohm and 120 Ohm resistance in terms of its limits.

Mnemonic to remember:

5





5





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Carbon film resistors: Most general purpose, cheap resistor Tolerance of resistance value is usually +/- 5 % Power ratings of 1/8 W, 1/4 W, and 1/2 W are usually used Con: Tend to be electrically noisy

Metal film resistor: Used when higher tolerance is needed, ie more value They have about +/- 0.05 % tolerance

Wire wound resistors: A wire wound resistor is made of metal resistance wire, and because of this they can be

manufactured to precise values Also, high wattage resistors can be made by thick wire material Have very high power ratings

Familiarization of Capacitor:


1. Provides definition of capacitance and name its unit2. Explain how capacitor can be constructed to give a particular value of capacitance3. Explain why capacitor has maximum working voltage4. Determine experimentally the energy stored in the capacitor

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5. Identify the value and type of capacitor6. Determine the polarity of terminals

What is a capacitor?

A capacitor is an electronic component which has a wide range of uses in various circuits due to theirability to store charge.

There are several types of capacitors which will vary in its construction but all will function in the similarway

Construction of capacitor:

The basic construction of all capacitor is that it consists of two parallel metal plates separated by aninsulating medium (dielectric). An insulator is a medium which is non- conducting i.e. it shows highresistance to the path of letting to electric current flow through it.

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For a capacitor the simplest type of capacitor used is air. Other types are oil or paper. Real capacitors aremade by taking thin strips of metal foil and the appropriate dielectric medium and sandwiching them.Capacitor achieves large area (thus large capacitance) by taking a large area of foil sandwiching theinsulating medium and rolling them in form of a cylinder. Capacitor is so called because of its capacity tostore energy. Capacitor are marked by a value indicating its capacitance i.e. their ability to store charge.Capacitance can be thought of as the electrical capacity of the body. It is measured in Farads.

Maximum working voltage:

If the voltage across the capacitor plates is too high the insulator between the plates fails to insulate andcharge passes from one plate to another. Capacitors are usually marked with the working voltage to avoidthis situation. A good thumb rule is that never place a voltage to the capacitor which exceed two third ofits maximum voltage especially in alternating current circuits.

Function of capacitor:

Consider a circuit set up i.e the capacitor is connected inseries with the ammeter and the switch is closed.

The ammeter will show

1. Steady state reading2. A reading of zero3. Flip back and forth4. Flip on one side and come back to zero.

Now let us extend this by using a galvanometer on bothsides of the capacitor and using a two way switch

If the switch is connected to ‘p’ then

1. Neither moves2. Both flick briefly to left3. Both flick briefly to right4. They flick briefly in opposite directions

Now if the switch is connected to the ‘o’ terminal:


If instead of first moving it to ‘p’ if it’s moved to ‘o’then it might be the possibilities as mentioned above.

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From the behavior of the ammeter needle it suggests that the current first flows in one way and then itflows in the other direction when the switch is moved from ‘p’ to ‘o’

So this suggests that

1. Equal amount of current flows off from one plate to the other2. More charge flows of from plate A onto B3. More charge flows of from plate B onto A4. No charge flows at all

Charging and discharging of capacitor:

We can say that capacitor is charged when connected to P and discharged when connected to terminal O

Charging:

The plate of the capacitor that is connected to the negative terminal of the battery accepts electrons thatthe battery is producing. The plate of the capacitor that is connected to the positive terminal of the batteryloses electrons to the battery. Once it is charged, the capacitor has the same voltage as that of the battery.

Let us connect a battery a light bulb and a capacitor in series. What are the possibilities that are about tohappen?

1. The bulb will glow as long as the battery is connected2. It will never glow3. It will first glow and then dimming of slowly and then finally turns off

If we then remove the battery and replace it with a wire, current will flow one plate of the capacitor to theother. The bulb will glow initially and then dim as the capacitor discharges, until it is completely out.

A static description of a capacitor behavior is understood by the expression

Q = CV where Q is the total charge, C signifies how big the capacitor is and V is the voltage across it.

The dynamic description i.e. the one which changes with time is given by the equation.

I = dV/dt

This is just time derivative of static description, ‘C’ is theconstant with respect to time and ‘I’ is the rate at which chargeflows.

This essentially shows that the bigger the current the faster thecapacitor’s voltage changes.

Analogy:

Think of capacitor as a tub that can hold charge. A tub of largediameter (C), holds a lot of water (Q) for a given height (V). Ifwe fill the tub with a thin straw (small I) then water level –V-

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Charging:








I = dV/dt



Analogy:


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Charging:








I = dV/dt



Analogy:


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will rise slowly. If we use a large pipe (large V) then water level will rise faster. Similar for draining(discharging) tub. Of course a tub of larger diameter takes longer to fill than a tub of smaller diameter.

Classification of Capacitors:

Polarized: They have a positive and negative electrode.o Electrolytico Tantalumo Super

Un-Polarized: They don’t have a positive and negative electrode indicationo Ceramico Multilayer ceramico Polystyrene filmo Polyester filmo Polypropyleneo Mica

Electrolytic capacitor:

Electrolytic capacitors are polarized and they must be connected thecorrect way round. It is easy to find the value of electrolytic capacitorsbecause they are clearly printed with their capacitance and voltagerating.

Tantalum capacitors:

Tantalum bead capacitors are polarized and have low voltage ratings likeelectrolytic capacitors. Usually, the ‘+’ symbol is used to show thepositive component lead. Modern tantalum bead capacitors are printedwith their capacitance, voltage and polarity in full. However older onesuse a color-code system which has two stripes (for the two digits) and sspot of color for the number of zeros to give the value in F.

Un-Polarized capacitors - small values upto 1F:

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Un-Polarized capacitors – Number code:

Un-Polarized capacitors – Color code:

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Familiarization of inductor:


Explain function of inductor Explain the factors influencing inductance

Function of an inductor:

The function of a value is to control the amount of fluid thatflows through a pipe.

In an electric circuit, the resistor is used to control the amount ofcurrent that flows through a conductor.

Another device that controls the current is the inductor:

However unlike the resistor that affects the current uniformly at alltimes, the inductor only affects currents when they are changing invalue.

Similarity with capacitor:

Rate of change of voltage in a capacitor depends upon thecurrent through it

Rate of change of current in an inductor depends upon thevoltage applied across it.

Like capacitive current, inductive current is not simplyproportional to voltage.

Unlike the situation in a resistor, the power associated withinductive current (V times I) is not turned into heat but is stored as energy in the inductor’smagnetic field.

V = L*dI/dt, Where, L is the inductance and is measured in henry.

Putting a voltage across an inductor causes the current to rise as a ramp. 1 volt across 1 henry produced a current that increases at 1 amp per second

Structure of an Inductor:

It consists of a wire wound as a coil around a core. The core may consist of a air filled hollow tube orsolid material.

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Inductance:

The amount of inductance in henries a coil has, is determined by the following factors:

Inductive Kick:

An inductor is capable of producing a momentary voltage that is muchhigher than the voltage of the power source that supplied the current tocreate its magnetic field. This temporary voltage is called an inductivekick.

Example of applications of inductive devices to provide an inductivekick is a combustion engine ignition system that creates the sparkacross the gap of the spark plug.

Result:The basic fundamentals of passive elements have been studied.

Learning outcome: To be written by students in 50-70 words.

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Inductance:


Inductive Kick:





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Inductance:


Inductive Kick:





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EXPERIMENT NO. 2

Wiring of different lamp control, stair casing circuits, Assembly and wiring of fluorescent tube light.

To control one lamp with the help of Two way switch

Material Used: Switch board, Two way switch, Lamp holder, PVC wires, Switch sheet, Casing &Capping batten, Lamp, Nail & Screw

Tool used: Combination pleir, Test pen, Screw driver, Knife, Poker

Learning objective: Assembly and wiring of fluorescent tube light

Circuit Diagram:

Outline of Procedure:

1) Take a wooden board.

2) Fixed casing & capping on wooden board & fixed three switch board at the end of casing & capping

batten two for 2 way switch & one for Lamp.

3) Fixed Lamp holder on board.

4) Connect Phase wire to lamp holder through switch.

5) Connect neutral wore directly to lamp holder.

6) Check the circuit before connecting main supply.

Precautions:

1) All connection should be tight.2) Wire should not over long.3) After completing the job all tools must be kept at proper place.4) Keep your mind and eyes on the job & don’t talk any one while working.5) Tools not being used should not be scatter on working table.

Learning outcome: To be written by students in 50 to 70 words

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Lay out of complete house wiring with batten wiring with lamp, fan, tube light.

Equipment/Tool Used: 1- phase energy meter, DP main switch, fuse, neutral link, Combination pliers, screwdriver, test pen, side cutting plier, and electrician knife.

Consumable Material: PVC Wire, Screw, PVC Batten, , Lamp holder, switch sheet, switch board, Insulationtape, fuse wire, lamp, tube fitting.

Learning Objective: To practice how to make the connection of house wiring and domestic appliances.

Outline of Procedure:Fixed 1-phase energy meter, DP main switch and switch board on their on respectiveplaces.Make the connection as per circuit diagram.Connected phase wire to lamp, socket, tube light and fan through switch and connectneutral directly.Now, switch on the power supply and job will the function.

Result:1. Analysis of the connection of domestic wiring.2. Proper connection of lamp, tube light and fan.

Precaution:1. Connection should be tightly done.2. Keep your mind and eyes on the job and don’t talk any one while working.3. Tools being used should not be allowed to scatter on working table.

.Learning Outcome: To be written by students in 50-70 words

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Assembly and wiring of fluorescent tube light

Equipment/ Tool Required: Combination pleir, test pen, screw driver, knife, poker

Learning Objective: To practice how to make the connection of tube light.

Reference Drg. No. LPU/ELECT/04(b)

Circuit Diagram:


1) Make the tube light circuit as shown in circuit diagram.2) Connect phase wire through switch.3) Connect neutral wire directly to tube rod.4) Connect starter to two spare terminals.

Result: Now we are familiar with making a tube light circuit

Learning Outcome: To be written by students in 50-70 words

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EXPERIMENT NO. 3

Distribution board (To make a single phase main distribution board with five outgoing circuits for lightand fan load including main switch and fuses (only internal connections), Wiring and testing of alarmand indicating relays, indicating lights etc.)

To prepared a distribution board with four outgoes circuit for fan and light loadalong with main switch and fuses

Equipment/ Tool Required: Plier, Screw Driver, Test pen, Claw hammer, Poker, Knife, Energy meter,DP main

Switch, Distribution box 4-way, MCB 6A, Neutral link.

Consumable Material: PVC Wire, Screw, PVC Batten, Switch, Lamp holder, switch sheet, switchboard.

Learning Objective: In this the student knows how to divide the load to different circuit.


1. First of all we fixed energy meter, main switch, and distribution box on woodenboard and a Bus bar and neutral link fused in distribution box.

2. Now Connect Phase wire to bus bar and neutral wire to Neutral link.3. One Phase wire taken from main bus bar and neutral wire from Neutral Link

through fuse or MCB each ckt is made from pair of Phase and Neutral wire.

Result: In this system the number of ckt and Sub ckt are divided on the basis of Load to be connectedto the supply.


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EXPERIMENT NO. 4

PN Junction Diode (To study the VI characteristics of PN junction diode and Zener diode)

Plotting V-I characteristics of PN junction diode:

Equipment Required: Diode D1N4002, Resistor 1 kὩ, Multimeter , Wires.

Material Required: Bread board, connecting wires

Software Required: Pspice

Learning Objective: Study of characteristics of a diode.

Circuit diagram:


Connect the circuit as per circuit diagram. Use PSpice to obtain the i-v characteristic of the diode with model number D1N4002.

Sweep the input voltage from -15 V to 15 V. When simulation is complete probe graphic window appears. Add the trace I (D1).

This is the trace of the diode current versus the supply voltage Vss. We need to changethe x-axis variable to V (Vd) to obtain the plot of diode current versus diode voltage. Todo this from the Plot pull-down menu select X Axis Settings, click the Axis Variablebutton to open the variable list, and select V (Vd) to be the horizontal axis.

After performing the simulation, implement the same on the bread board to draw VIcharacteristics of PN junction diode.

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Ideal graph:

Plotting V-I characteristics of Zener diode:

Equipment Required: Zener Diode D1N750, Resistor 1 kὩ, Multimeter .

Material Required: Bread board, connecting wires

Software Required: Pspice

Learning Objective: Study of characteristics of a Zener diode.

Circuit diagram:

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Construct the above schematic and label the output node as Vout. Select the setup fromthe analysis menu; click the DC Sweep dialog button. The DC sweep dialog boxappears. For the Sweep variable type select the voltage source, and set its name to V1.Using the sweep type linear, set the starting value to 0, end value to 20 and incrementto 0.05.When simulation is complete probe graphic window appears. From the Plot pull-downmenu select X Axis Settings, click the Axis Variable button to open the variable list,and select V (Vout) to be the horizontal axis.

Ideal graph:

Scope of result to be reported: Observe the V-I Curves of PN and Zener diode inPSPICE window.

Cautions:Connect circuit very carefully with all components from proper Library.

Result: In this, we studied the characteristics of PN junction and Zener diode.


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EXPERIMENT NO. 5

Voltage regulator (Implementation of voltage regulator using Zener diode)

Voltage regulator:

Learning Objective: To know about voltage regulation

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RESULT- In this, we studied how Zener diode acts as voltage regulator.

Precautions:Connect circuit very carefully with all connections tight and clear.Do not short circuit +ve and - ve terminals of supply at any point in circuit.

Learning Outcome: To be written by students in 50-70 words.

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EXPERIMENT NO. 6

Rectifier (Implementation of half wave and full wave rectifier using diodes on bread board andalso on Pspice)

Half wave rectifier:

Learning Objectives:To recognize a half-wave rectified sinusoidal voltage.To understand the term ‘mean value’ as applied to a rectified waveform.To understand the effect of a reservoir capacitor upon the rectified waveform and

its mean value

Apparatus: Diode, Wires, Power supply, resistor, capacitor.

Simple Half-Wave Rectification

Circuit diagram:


Switch on the oscilloscope and the sinusoidal supply. With the oscilloscope d.c. coupled adjust the time-base and the Y amplifier sensitivity

to obtain a steady trace of about 4cm vertical and 5ms/cm horizontal. Measure and record time T and peak voltage Vpk: Sketch the waveform and label it to show the periods when the diode is conducting

and those when it is not. Time T depends upon the frequency of your power supply.

Confirm this. Vpk should be very nearly equal to the peak voltage of the alternatingsupply

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Output waveforms:

Full wave rectifier:

Circuit diagram:

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Switch on the sinusoidal supply. Measure and record time mean value of output voltage indicated on the voltmeter Vm. Compare the mean value of output voltage indicated on the voltmeter those obtained

in the Half-Wave rectification.

Output waveforms:

Result:

Rectification of Halfwave and fullwave using diodes have been studied.



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Output waveforms:

Result:




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Output waveforms:

Result:




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EXPERIMENT NO. 7

Resonance (To verify series and parallel resonance in AC circuits)

Series resonance:

Appartaus Required-

Equipment Range Quantity

Signal generator 0-1 MHz 1

Voltmeter 0-10V 3

Ammeter 0-10mA 1

Learning Objective: Resonance in AC circuits

Circuit Diagram-


1. Set up the circuit as shown in circuit diagram2. Set input voltage =5V using signal generator and vary the frequency from 0-1 MHz in regular

steps.3. Note down the corresponding output voltage and current.4. Plot the following graph

a. Current v/s frequenciesb. Voltage v/s frequencies

5. To measure the resonance frequency:

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a. Plot the graph current v/s frequenciesb. Draw a horizontal line, which intersects the curve at 1/sqrt(2) times the maximum

current readingc. Lower intersected point and upper intersected point are respectively called lower cut

off frequency and upper cut off frequency on frequency axis

BANDWIDTH:

BW=f2-f1

BW=ω0/Q

ωn=√ω1ω2

SELECTIVITY:

S=1/Q

S=R/ω0L

Model graph:

Tabulation:

Frequency (Hz) Output Circuit(mA)

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Parallel resonance:

Equipment Required-

Equipment Range Quantity

Signal Generator 0-1 MHz 1

Voltmeter

Ammeter

Circuit Diagram-


1. Set up the circuit as shown in fig2. Set input voltage =5V using signal generator and vary the frequency from 0-1 MHz in regular

steps3. Note down the corresponding output voltage and current4. Plot the following graph: Impedance v/s frequency5. To measure the resonance frequency:

a. Plot the graph Impedance v/s frequencyb. Draw a horizontal line, which intersects the curve at 1/sqrt(2) times the maximum

impedance readingc. Lower intersected point and upper intersected point are respectively called lower cut

off frequency and upper cut off frequency on frequency axis

QUALITY FACTOR:

Q0=R/ω0L=R√(C/L)

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BANDWIDTH & SELECTIVITY-

BW=f2-f1

SELECTIVITY=BW/f0=(f2-f1)/f0

Model graph:

Tabulation-

Vi = 5 V

Frequency (Hz) Current (mA) Z=Vi/I

Result:

Series and parallel resonance in AC circuit have been studied.



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BW=f2-f1


Model graph:

Tabulation-

Vi = 5 V


Result:




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BW=f2-f1


Model graph:

Tabulation-

Vi = 5 V


Result:




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EXPERIMENT NO. 8

Bipolar junction transistor (To study the VI characteristics of Bipolar junction transistor)

CB configuration:

Learning Objective:- To plot the transistor characteristics of CB configuration.

THEORY:

In this configuration the base is made common to both the input and out. The emitter is given theinput and the output is taken across the collector. The current gain of this configuration is lessthan unity. The voltage gain of CB configuration is high. Due to the high voltage gain, the powergain is also high. In CB configuration, Base is common to both input and output. In CBconfiguration the input characteristics relate IE and VEB for a constant VCB. Initially let VCB =0 then the input junction is equivalent to a forward biased diode and the characteristics resemblesthat of a diode. Where VCB = +VI (volts) due to early effect IE increases and so thecharacteristics shifts to the left. The output characteristics relate IC and VCB for a constant IE.Initially increased IC also increases. proportionality. Though increase in VCB remains a constantfor all values of VCB once it levels off.

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Input characteristics:

It is the curve between emitter current IE and emitter-base voltage VBE at constant collector-base voltage VCB.1. Connect the circuit as per the circuit diagram.2. Set VCE=5V, vary VBE in steps of 0.1V and note down the corresponding IB. Repeat theabove procedure for 10V, 15V.3. Plot the graph VBE Vs IB for a constant VCE.

Output characteristics:

It is the curve between collector current IC and collector-base voltage VCB at constant emittercurrent IE.

1. Connect the circuit as per the circuit diagram.2. Set Ib=20 mA, vary Vce in steps of 1 V and note down the corresponding Ic.repeat the

above procedure for 40 mA,80 mA etc..3. Plot the graph VCE Vs IC for a constant IB.4. Find the h parameters .

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Results:

Fill in the observed response in the following table and design the characteristics on its basis.


CE configuration:

Learning Objective:- To plot the transistor characteristics of CE configuration.

Outline of procedure:


1. Connect the circuit as per the circuit diagram.

2. Set VCE ,vary VBE in regular interval of steps and note down the corresponding IBreading. Repeat the above procedure for different values of VCE.

3. Plot the graph: VBE Vs IB for a constant VCE.

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Results:



CE configuration:







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Results:



CE configuration:







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2. Set IB, Vary VCE in regular interval of steps and note down the corresponding ICreading. Repeat the above procedure for different values of IB.

3. Plot the graph: VCE Vs IC for a constant IB.

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Model graph:

Result: The transistor characteristics of a Common Emitter (CE) configuration wereplotted.


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Model graph:



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Model graph:



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EXPERIMENT NO. 9

DC motor (Realization of the Direction control for DC motor circuit)

Direction control of DC motor:

Equipment Required: Wires, Multiple Power Supply & multimeter.

Material Required: Resistor (10K, 2.2 K -2 each), Diodes (IN4007-5), Transistor (instead of TIP31 useBC 548) and DC motor (12V).

Learning Objective: Direction control of DC motor using transistors.

Outline of Procedure: Connect circuit as per as the circuit diagram. Operate switches S1 and S2 to direction control of

DC motor.Circuit Diagram:

Scope of result to be reported: Observe the direction of rotation of motor as we turn on the switchesS1 and S2 alternately.



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EXPERIMENT NO. 10

Thyristor (Study the VI characteristics of a thyristor)

VI characteristics of a Thyristor:

Apparatus required:

SCR – TY604, power supplies, wattage resistors, ammeter, voltmeter.

Learning Objective: To study the VI characteristics of a Thyristor

Circuit Diagram:


Connections are made as shown in the circuit diagram. The value of gate current Ig, is set to convenient value by adjusting VGG By varying the anode – cathode supply voltage VAA gradually in step by step, note down the corresponding

values of VAK and IA. Note down VAK and IA at the instant of firing of SCR and after firing (by reducing thevoltmeter ranges and in creasing the ammeter ranges) then increase the supply voltage VAA. Note downcorresponding values of VAK and IA

The point at which SCR fires, gives the values of break over voltage VBO A graph of VAK vs IA is to be plotted The ON state resistance can be calculated from the graph by using a formula The gate supply voltage VGG is to be switched off Observe the ammeter reading by reducing the anode-cathode supply voltage VAA. The point at which the

ammeter reading suddenly goes to zero gives the value of holding current IH. Steps no. 2 to 8 are repeated for another value of the gate current IG.

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EXPERIMENT NO. 10



Apparatus required:



Circuit Diagram:






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EXPERIMENT NO. 10



Apparatus required:



Circuit Diagram:






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Tabular column:

Ig = ________mA Ig = ________mA

S.NO VAK (V) IA (A/mA/A) S.NO VAK (V) IA (A/mA/A)

Result :

V-I characterstics of SCR have been studied.

Precautions:Connect circuit very carefully with all connections tight and clear.Do not short circuit +ve and ve terminals of supply at any point in circuit.


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Tabular column:

Ig = ________mA Ig = ________mA


Result :




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Tabular column:

Ig = ________mA Ig = ________mA


Result :




electronics lab manual

Documents

short circuit ve

bipolar junction transistor

pn junction diode

phase energy meter

axis variable button

full wave rectifier

dp main switch

wire wound resistors