circuits and devices lab manual

8/13/2019 Circuits and Devices lab manual

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CIRCUIT DIAGRAM:

Forward Bias Condition

Reverse Bias Condition

Pin Diagram


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Experiment No: Date:

Characteristics of PN Junction Diode

AIM:

To draw the voltage current characteristics of PN junction diode under forward and

reverse bias condition and to determine cut in voltage, static and dynamic resistance.

APPARATUS REQUIRED:

S.NO. NAME OF THE EQUIPMENT TYPE RANGE QUANTITY

1 Diode IN4007 1

2 Resistor 220 1

3 Voltmeter MC (0-1) V

(0-30) V

One Each

4 Ammeter MC (0-100)mA

(0-500)A

One Each

5 Dual Regulated Power Supply (0-30)V 1

6 Bread Board -- -- 1

7 Connecting Wires -- -- Required

FORMULA USED:

DC (or) Static Resistance, (Rf) = Vf/ If

AC (or) Dynamic Resistance, rf= Vf/ If

Where,

VfChange in Voltage in forward bias condition in Volts

If Resulting Change in current in forward condition in Amps

THEORY:

A PN junction diode conducts only in one direction. It is an example of unilateral element.The V-I characteristics of the diode are curve between voltage across the diode and currentthrough the diode. When external voltage is zero,

PROCEDURE

FORWARD CHARACTERISTICS:1. Connections are made as per the circuit diagram.

2. Keep the RPS in minimum value and switch ON the power supply.

3. Gradually increase the forward voltage in step by step of variation,

Note down the forward voltage and current values and graph is plotted.


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TABULATION

S.No Forward Bias Reverse Bias

ForwardVoltage(Vf)volts

ForwardCurrent(If)mA

ReverseVoltage(Vf)volts

ReverseCurrent(If)A

CALCULATION


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REVERSE CHARACTERISTICS:

1. Connections are made as per the circuit diagram.


3. Gradually increase the reverse voltage in step by step of variation, Note

down the reverse voltage and current values and graph is plotted.

RESULT

Thus the forward and reverse V-I characteristics of a diode were obtained and

the characteristics curves were plotted.

DC (or) Static Resistance, (Rf) =

AC (or) Dynamic Resistance, (rf ) =

Cut in Voltage =

VIVA QUESTIONS:

1. What is semiconductor material? How does it differ from a conductor?

2. Why do we prefer extrinsic semiconductor than intrinsic semiconductors?

3. Define the term drift current?

4. Define the term diffusion current?

5. What is PN junction diode?

6. What is depletion region in a PN junction diode?

7. Define the term transition capacitance CT of a diode?

8. Explain the terms knee voltage and breakdown voltage with respect to diodes?

9. List the application of PN junction diode?

10. What is avalanche breakdown in PN junction diode?


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CIRCUIT DIAGRAM:

Forward Bias Condition

Reverse Bias Condition


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Zener diode Characteristics & Regulator using Zener diode

AIM:

a. To draw the voltage current characteristics of Zener diode under forward and

reverse bias condition and to determine cut in voltage, Breakdown voltage, static

and dynamic resistance.

b. To construct a voltage regulator using Zener diode and plot the regulation

characteristics.

APPARATUS REQUIRED:


1 Diode Z9.0 1

2 Resistor 220 13 Voltmeter MC (0-1) V

(0-30) V

One Each

4 Ammeter MC (0-100)mA 1


6 Bread Board 1

7 Connecting Wires Required

FORMULA USED:

DC (or) Static Resistance, (Rf) = Vf/ If

AC (or) Dynamic Resistance, rf= Vf/ If

Where,

VfChange in Voltage in forward bias condition in Volts

If Resulting Change in current in forward condition in Amps

Theory:

A zener diode is heavily doped p-n junction diode, specially made to operate in the

breakdown region. A p-n junction normally does not conduct when reverse biased. But if the

reverse bias is increased, at a particular voltage it starts conducting heavily. This voltage is

called breakdown voltage. High current through the diode can permanently damage the

device. In zener diode, the reverse breakdown occurs at low voltages, so the flow of heavy

current can be avoided. Once the diode starts conducting it maintains almost constant

voltage across the terminals, whatever the current flowing through it. It has very low

dynamic resistance. It is used in voltage regulators.


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Zener Diode Voltage Regulator

MODEL GRAPH:

V-I Characteristics of Zener Diode

V Vs I


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Procedure

FORWARD CHARACTERISTICS:



3. Gradually increase the forward voltage in step by step of variation,

Note down the forward voltage and current values and graph is plotted.

REVERSE CHARACTERISTICS:




down the reverse voltage and current values and graph is plotted.

Voltage Regulator:




down the reverse voltage and graph is plotted.


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Voltage Regulation Characteristics of Zener Diode

TABULATION

S.No Forward Bias Reverse Bias

ForwardVoltage(Vf)volts

ForwardCurrent(If)mA

ReverseVoltage(Vf)volts

ReverseCurrent(If)A


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CALCULATION

Result

Thus the forward and reverse V-I characteristics of a diode were obtained and

the characteristics curves were plotted.

DC (or) Static Resistance, (Rf) =

AC (or) Dynamic Resistance, (rf) =

Cut in Voltage =

Breakdown Voltage =

VIVA QUESTIONS:

1. What is Zener diode?

2. Give applications of Zener diode.

3. Does the dynamic impendence of a zener diode vary?

4. Explain briefly about avalanche and zener breakdowns.

5. Draw the zener equivalent circuit.

6. What is Zener voltage?

7. Which region zener diode can be used as a regulator?

8. How the breakdown voltage of a particular diode can be controlled?

9. What is voltage regulation of Zener diode?

10. By what type of charge carriers the current flows in zener and avalanche breakdown

diodes?


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CIRCUIT DIAGRAM:

MODEL GRAPH:

INPUT CHARACTERISTICS OUTPUT CHARACTERISTICS


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Common Emitter Input-Output Characteristics

AIM:

To plot the transistor characteristics of Common Emitter configuration.APPARATUS REQUIRED:


1 Transistor BC107 1

2 Resistor 10 K

1 K

One Each


(0-30) V

One Each


(0-100)mA

One Each

5 Dual Regulated Power Supply (0-30)V 16 Bread Board 1


FORMULA USED:

Input Impedance = VBE/ IB

Output Admittance = IC/ VCEmho

Current Gain = IC/ IB

Voltage Gain = VCE/ VBE

THEORY:

A BJT is a three terminal two junction semiconductor device in which the conduction is

due to both the charge carrier. Hence it is a bipolar device and it amplifier the sine

waveform as they are transferred from input to output. BJT is classified into two types

NPN or PNP. A NPN transistor consists of two N types in between which a layer of P is

sandwiched. The transistor consists of three terminal emitter, collector and base. The

emitter layer is the source of the charge carriers and it is heartily doped with a moderate

cross sectional area. The collector collects the charge carries and hence moderate doping

and large cross sectional area. The base region acts a path for the movement of the chargecarriers. In order to reduce the recombination of holes and electrons the base region is

lightly doped and is of hollow cross sectional area. Normally the transistor operates with the

EB junction forward biased. In transistor, the current is same in both junctions, which

indicates that there is a transfer of resistance between the two junctions. One to this fact

the transistor is known as transfer resistance of transistor.


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PIN DIAGRAM

TABULATION

Input Characteristics

S.No VCE= V VCE= V

VBEin Volts IBin A VBEin Volts IBin A


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PROCEDURE:

INPUT CHARECTERISTICS:

1. Connect the circuit as per the circuit diagram.

2. Set VCE, vary VBE in regular interval of steps and note down the corresponding I B

reading. Repeat the above procedure for different values of VCE.

3. Plot the graph: VBEVs IBfor a constant VCE.

OUTPUT CHARACTERISTICS:


2. Set IB, Vary VCE in regular interval of steps and note down the corresponding IC

reading. Repeat the above procedure for different values of IB.

3. Plot the graph: VCEVs ICfor a constant IB.


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Output Characteristics

S.No IB= A IB= A

VCEin Volts ICin mA VCEin Volts ICin mA

CALCULATION


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RESULT:

The transistor characteristics of a Common Emitter (CE) configuration were plotted.

Input Impedance = VBE/ IB=

Output Admittance = IC/ VCE=

Current Gain = IC/ IB =

Voltage Gain = VCE/ VBE =

VIVA QUESTIONS:

1. What is bipolar junction transistor?

2. What are the different configurations of BJT?

3. What is thermal runaway?

4. Define the different operating region of transistor?

5. List the uses of emitter follower (common collector configuration) circuit?

6. Define alpha and beta of the transistor?

7. What is meant by early effect?

8. Explain the significance of early effect or base width modulation?

9. Which configuration provides better current gain?

10. What is the significance of VBE and ICO?


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CIRCUIT DIAGRAM:

MODEL GRAPH:

PIN DIAGRAM


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Common Base Input-Output Characteristics

AIM:

To plot the transistor characteristics of Common Base configuration.

APPARATUS REQUIRED:


1 Transistor BC107 1

2 Resistor 10 K

1 K

One Each


(0-30) V

One Each


(0-100)mA

One Each


6 Bread Board 1


FORMULA USED:

Input Impedance = VEB/ IE

Output Admittance = IC/ VCBmho

Current Gain = IC/ IE

Voltage Gain = VCB/ VEB

THEORY:

In this configuration the base is made common to both the input and out. The emitter is

given the input and the output is taken across the collector. The current gain of this

configuration is less than unity. The voltage gain of CB configuration is high. Due to the high

voltage gain, the power gain is also high. In CB configuration, Base is common to both input

and output. In CB configuration 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 resembles that of a diode. Where VCB = +VI (volts) due to early effect

IE increases and so the characteristics shifts to the left. The output characteristics relate IC

and VCB for a constant IE. Initially IC increases and then it levels for a value IC = IE.

When IE is increased IC also increases proportionality. Though increase in VCB causes an

increase in , since is a fraction, it is negligible and so IC remains a constant for all values

of VCB once it levels off.


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Input Characteristics

S.No VCb= V VCb= V

VBEin Volts IEin mA VBEin Volts IEin mA

Output Characteristics

S.No IE= mA IE= mA

VCbin Volts ICin mA VCbin Volts ICin mA


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PROCEDURE:

INPUT CHARECTERISTICS:


2. Set Vcb, vary VBE in regular interval of steps and note down the corresponding IE

reading. Repeat the above procedure for different values of Vcb.

3. Plot the graph: VBEVs IEfor a constant VCb.

OUTPUT CHARACTERISTICS:


2. Set IE, Vary VCb in regular interval of steps and note down the corresponding IC

reading. Repeat the above procedure for different values of IE.

3. Plot the graph: VCbVs ICfor a constant IE.


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CALCULATION


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RESULT:

The transistor characteristics of a Common Base (CB) configuration were plotted.

Input Impedance = VEB/ IE=

Output Admittance = IC/ VCB=

Current Gain = IC/ IE =

Voltage Gain = VCB/ VEB =

VIVA QUESTIONS:

1. What are the types of breakdown occurs in transistors?

2. Why do we prefer silicon for transistor?

3. What is meant by stabilization?

4. What is the need for biasing?

5. What is meant by operating point?

6. What types of components are used for temperature stabilization?

7. What are the types of biasing?

8. Define stability factor?

9. What is Q point?

10. What is bias? What is the need for biasing?


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CIRCUIT DIAGRAM:

MODEL GRAPH:


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FET Characteristics

AIM:

To obtain the Drain and Transfer (V-I) characteristics of FET and to plot thecharacteristics.

APPARATUS REQUIRED:


1 FET BFW 10

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1

2 Resistor 1 K 2

3 Voltmeter MC (0-30) V 2

4 Ammeter MC (0-100)mA 15 Dual Regulated Power Supply (0-30)V 1

6 Bread Board 1


FORMULA USED:

Drain Resistance Rd = VDS/ ID, VGSas constant

Transconductance gm = ID/ VGS, VDSas constant

THEORY:

FET is a voltage operated device. It has got 3 terminals. They are Source, Drain & Gate.

When the gate is biased negative with respect to the source, the pn junctions are reverse

biased & depletion regions are formed. The channel is more lightly doped than the p type

gate, so the depletion regions penetrate deeply in to the channel. The result is that the

channel is narrowed, its resistance is increased, & ID is reduced. When the negative bias

voltage is further increased, the depletion regions meet at the center & ID is cutoff

completely.


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Drain Characteristics

S.No VGS= V VGS= V

VDSin Volts ID in mA VDSin Volts ID in mA

Transfer Characteristics

S.No VDS= V VDS= V

VGSin Volts ID in mA VGSin Volts ID in mA


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PROCEDURE:

DRAIN CHARACTERISTICS:


2. Set the gate voltage VGS= 0V.

3. Vary VDSin steps of 1 V & note down the corresponding ID.

4. Repeat the same procedure for VGS= -1V.

5. Plot the graph VDSVs IDfor constant VGS.

TRANSFER CHARACTERISTICS:


2. Set the drain voltage VDS= 5 V.3. Vary the gate voltage VGSin steps of 1V & note down the corresponding ID.

4. Repeat the same procedure for VDS= 10V.

5. Plot the graphVGSVs IDfor constant VDS.


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CALCULATION


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RESULT:

Thus the Drain & Transfer characteristics of given FET is Plotted.

Drain Resistance Rd = VDS/ ID=

Transconductance gm = ID/ VGS =

VIVA QUESTIONS:

1. What is a FET?

2. Why FET is called an unipolar device?

3. Define pinch off voltage?

4. Define drain resistance?

5. Write down the relationship between various FET parameters?

6. Mention the application of FET?7. Why the input impedance of FET is more than that of a BJT?

8. What is meant by gate source threshold voltage of a FET?

9. Why N channel FETs are preferred over P channel FETs?


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CIRCUIT DIAGRAM:

MODEL GRAPH:

V-I Characteristics of SCR


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SCR Characteristics

AIM:

To obtain the V-I characteristics of SCR.

APPARATUS REQUIRED:


1 SCR TYN612

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1

2 Resistor 1 K

10 K

1

1

3 Voltmeter MC (0-10) V 1

4 Ammeter MC (0-50)mA 15 Dual Regulated Power Supply (0-30)V 1

6 Bread Board 1


THEORY:

A Silicon Controlled Rectifier (SCR) is 3 terminals consisting of four semiconductor layers

forming a PNPN structure. It has three PN junctions namely J1, J2and J3. There are three

terminals called Anode, Cathode and the gate. The SCR resembles the diode electrically,

since it conducts the current in one direction only, when forward biased. However the SCR is

different from diode because it has an additional gate terminal. This gate is used to turn

ON the device.

When the anode is more positive with respect to the cathode, junctions J 1& J3are forward

biased and the junctions J2is reverse biased. Only a small leakage current flows through the

device. The device is said to be in t he forward blocking state or off state or cutoff state.

When the anode to cathode voltage is increased to break over value, the junction J2breaks

down and device starts conducting (ON state) the anode current must


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Transfer Characteristics

S.No IG= mA IG= mA

VAKin Volts IAK in mA VAKin Volts IAK in mA

CALCULATION:


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be more than the value known as latching current in order to maintain the device in the ON

state. Once SCR starts conducting, it behaves like a conducting diode and gate has no

control over the device. The device can be turned off only by bringing the device in below a

value known as holding current. The forward voltage drop across the device in the ON stateis around one volt. When the cathode voltage is made positive with respect to the anode

voltage junction J2 is forward biased and the junction J1 and J3are reversed biased. The

device will be in the reverse blocking state and only small leakage current flows through the

device. The device can be turned on at forward voltage less than break over voltage by

applying suitable gate current.

PROCEDURE:

1. Connections are made as per circuit diagram.

2. Keep the gate supply voltage at some constant value

3. Vary the anode to cathode supply voltage and note down the readings of voltmeter and

ammeter. Keep the gate voltage at standard value.

4. A graph is drawn between VAK and IAK.

5. From the graph note down the threshold voltage and Holding current values.

RESULT:

The V-I Characteristics of the SCR have been plotted.

Threshold Voltage =

Holding Current =

VIVA QUESTIONS:

1. What the symbol of SCR?

2. In which state SCR turns of conducting state to blocking state?

3. What are the applications of SCR?

4. What is holding current?

5. What are the important types thyristors?

6. How many numbers of junctions are involved in SCR?

7. What is the function of gate in SCR?

8. When gate is open, what happens when anode voltage is increased?

9. What is the value of forward resistance offered by SCR?

10. What is the condition for making from conducting state to non conducting state?


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CIRCUIT DIAGRAM:

A) FULL WAVE RECTIFIER WITHOUT FILTER:

B) FULL WAVE RECTIFIER WITH FILTER:


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Full-Wave Rectifier

AIM:

To examine the input and output waveforms of Full Wave Rectifier and also calculate ripple

factor with Filter and without Filter.

APPARATUS REQUIRED:


1 Transformer (6V-0-6V) 1

2 Diode 1N4007 2

3 Capacitor 1000 F 1

4 Resistor 10 K 1

5 CRO and CRO Probes 16 Bread Board 1


THEORY:

The circuit of a center-tapped full wave rectifier uses two diodes D1&D2. During positive half

cycle of secondary voltage (input voltage), the diode D1 is forward biased and D2is reverse

biased. So the diode D1 conducts and current flows through load resistor RL. During

negative half cycle, diode D2 becomes forward biased and D1 reverse biased. Now, D2

conducts and current flows through the load resistor RL in the same direction. There is a

continuous current flow through the load resistor RL, during both the half cycles and will get

unidirectional current as show in the model graph. The difference between full wave and

half wave rectification is that a full wave rectifier allows unidirectional (one way) current to

the load during the entire 360 degrees of the input signal and half-wave rectifier allows this

only during one half cycle (180 degree).

THEORITICAL CALCULATIONS:

Vrms = Vm/ 2 Vdc=2Vm/

(i)Without filter:

Ripple factor, r = (Vrms/ Vdc )2-1 = 0.812

(ii)With filter:

Ripple factor, r = 1/ (43 f C RL)


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Model Graph

A) INPUT WAVEFORM

B) OUTPUT WAVEFORM WITHOUT FILTER

C) OUTPUT WAVEFORM WITH FILTER

TABULATION FOR FULL WAVE RECTIFIER:

Signal Amplitude(V) Time Period (ms) Frequency


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PROCEDURE:


2. The transformer is tested for rated voltage of primary and secondary.

3. CRO connected across the load.

4. Note the output waveforms with and without filters.

5. Calculate the ripple factor and compare with theoretical values

CALCULATION


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CALCULATION


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RESULT:

The input and output waveforms of Full Wave Rectifier are plotted.

Ripple factor with Filter =

Ripple factor without Filter =

VIVA QUESTIONS:

1. What is rectifier?

2. Classification of rectifier?

3. What is meant by ripples?

4. What do you mean by ripple factor?

5. Define rectification efficiency?

6. What is peak inverse voltage?

7. What is meant by full wave rectifier?8. Classify full wave rectifier?

9. What principle is used in FWR?

10.What is peak inverse voltage in FWR?

11.What are the disadvantages of full wave rectifier?


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Circuit Diagram:

(a)Positive Clipper

MODEL GRAPH:

(a)Negative Clipper


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Clipper and Clamper

AIM:

To examine the input and output waveforms of clipper and clamper.

APPARATUS REQUIRED:


1 Function Generator 1

2 Diode 1N4007 1

3 Capacitor 1 F 1

4 Resistor 1 K 1

5 CRO and CRO Probes 1

6 Bread Board 17 Connecting Wires Required

THEORY:

Clipper circuits have the ability to clip off a portion of the input signal without distorting

the remaining part of the alternating waveform. The half wave rectifier of the previous

experiment is an example of the simplest form of diode clipper. Depending on the

orientation of thy diode, the positive or negative region of the input signal is clipped off.

There are two general categories of clippers: series and parallel. The series c configuration

is defined as one where the diode is in series with the load, while the parallel variety has thediode in branch parallel to the load.

Sometimes you may want to leave the waveform unchanged, but modify its DC level up or

down. To accomplish this, you use a clamper circuit. The beauty of clampers is that they can

adjust the DC position of the waveform without knowing what the waveform actually is. In

the positive half of the first cycle, the voltage across the capacitor cannot change

instantaneously; therefore as the voltage on the input moves up, the voltage on the top of

the diode has to follow this voltage. This reverse biases the diode causing it to act as an

open, thus the output voltage follows the input voltage. As the input voltage drops into the

negative half of the first cycle, the diode is going to be forward biased. In the positive half

of the first cycle, the voltage across the capacitor cannot change instantaneously; therefore

as the voltage on the input moves up, the voltage on the top of the diode has to follow this

voltage.


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MODEL GRAPH:

(a)Positive Clamper

Model Graph


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This reverse biases the diode causing it to act as an open, thus the output voltage

follows the input voltage. As the input voltage drops into the negative half of the first cycle,

the diode is going to be forward biased. This causes the diode to behave like a wire, which

cannot dissipate any voltage.

PROCEDURE:


2. Set Sine wave of amplitude 10V (Peak-Peak) in the Signal generator.

3. CRO connected across the load.

4. Note the input, output waveforms for clippers and clampers.


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TABULATION FOR CLIPPER and CLAMPER:

TYPE AMPLITUDE (V) TIME (T)

Input Signal

Positive Clipper

Negative Clipper

Output Signal

Positive Clamper

Negative Clamper


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RESULT:

The input and output waveforms of Clipper and Clamper are plotted.

VIVA QUESTIONS:

1. What is clipper?

2. What is clipper?

3. What are the different types of clippers?

4. What are the different types of clampers?

5. What is the use of clipping circuits?

6. What is the use of clamping circuits?


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Circuit DiagramVERIFICATION OF THEVENINS THEOREM

Circuit Diagram

RPS

(0-30)V V(0-30)V

MC

1K 1K

2K

Fig (1)

RPS

(0-30)V

1K 1K

2K A (0-10)mA

MC


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Ex:No Date:VERIFICATION OF THEVENINS THEOREM

AIM:To verify the Thevenin`s theorem for the given electric circuit .

APPRATUS REQUIRED:

S.No Name of the Apparatus Range Quantity1 DC Regulated Power Supply (0-30)V 12 Resistor 2K 1

1K 23 Ammeter (0-10mA),MC 14 Voltmeter (0-30V),MC 15 Bread Board -- 1

Thevenin`s Theorem StatementThevenin`s theorem states that A circuit with two terminals can be replaced by anequivalent circuit consisting of a voltage source in series with a resistance (or) impedance

THEORYA linear, bilateral, lumped element with open output terminals can be reduced to a simplecircuit consisting of a single voltage source in series with a resistance. The value of thevoltage source is equal to the open circuit voltage across the open terminals and the valueof resistance is equal to the resistance seen in to the network across the open terminals.Consider the circuit given below

I

R1

2RE

3R

4R

The value of the current I is found using Thevenins theorem. First RL is disconnected and theterminal is opened .

R3

E R2

1R

thV Rth,


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TABULATION (from given circuit)S.No Input Voltage

(v)Theoretical Practical

Vth (V) Rth() IL(mA) Vth (V) Rth() IL(mA)

Equivalent Circuit

Tabulation (from Equivalent Circuit)S.No. Input Voltage

(V)Load Current

(mA)


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PROCEDURE1. Connections are made as per the circuit diagram.

2. RPS is switched on and kept at a constant value.

3. Load terminals AB is open circuited and a voltmeter is connected across R3to

measure the practical value of the Vth

4. Voltage source is measured with respect to terminal AB

5. Now the load resistor is connected to measure the load current

6. The value of load current is calculated the correctly and it is checked with the

practical value.

The voltage across the open circuit terminals is called as Thevenins Voltage Vth. Thevalue of Rthis found to after replacing the voltage source E by short circuit.

Thevenins Equivalent circuit is drawn with Vth and Rth. The disconnected element isplaced and the open circuit terminals of the Thevenins equivalent circuit.

thV

Thevenin's Equivalent circuit

RL

thR

The current through RLis found as


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Calculation


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Viva Questions

1. Steps to solve Thevenins Theorem2. Steps to solve Nortons Theorem3. What is the load current in a Nortons circuit?4. What is the load current in a Thevenins circuit?5. What is the max power in a circuit?6. Define active and passive network.7. Types of dependent sources?8. What are the limitations of theveninstheorem?9. What is Duality?

Inference

Result

Lab Performance 10

Observation 10

Viva 10

Total 30


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CIRCUIT DIAGRAM

RPS(0-30)V

220 100

330 RPS(0-30)V

RPS

(0-30)V

220 100

330 RPS

(0-30)V

A (0-10)mA

MC

RPS

(0-30)V

220 100

RPS

(0-30)VA

(0-10)mA

MC


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Ex:No: Date:

VERIFICATION OF NORTONS THEOREM

AIM:To verify the Norton`s theorem for a given electric circuit.

APPRATUS REQUIRED:

S.No Name of the Apparatus Range Quantity

1 DC Regulated Power Supply (0-30)V 12 Resistor 2.2K 3

10K 13 Ammeter (0-10mA),MC 14 Voltmeter (0-30mA),MC 15 Bread Board -- 1

NORTON`S THEOREM STATEMENT

A linear network containing sources and passive elements can be replace by anequivalent circuit consisting of a current source in parallel with a resistance or impedancewith respect to any two terminals

THEORY

A linear, bilateral, lumped element with open output terminals can be reduced to asimple circuit consisting of single current source in parallel with a resistance.

The value of current source is equal to the current passing through the short-circuited output terminals. The value of the resistance is equal to the resistance seen intothe network across the output terminal. Consider the given circuit

I

R1

3RE

3R

4R

R1

2RE

3R

NI


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TABULATI ON (FROM GIVEN CIRCUIT)

S.No I nput Voltage Theoretical Practical

IN (mA) RN(K) IL(mA) IN (mA) RN(K) IL(mA)

MODEL CALCULATION


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The current through the short circuited output terminals is called Norton Current IN. , the Rthvalue is found across the open circuit terminals as found in Thevenins theorem, after shortcircuiting the voltage source E.

Nortons equivalent circuit is drawn with INand Rth.

INI

Norton's Equivalent Circuit

RLthR

The disconnected element RLis placed across the open output terminal.

Now Norton equivalent circuit

INI

Norton's Equivalent Circuit

RLthR

Current through RLis found as


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EQUIVALENT CIRCUIT:

Vivaquestions

1.State Thevenins theorem.2.State Nortons theorem.3.Steps to solve Thevenins Theorem.4. Define electrical Potential or Voltage.5.What is meant by resistance?6.Define Conductance.7.Define Electric power.8.What is the result of resistance in series?9.What is the Result of resistance in parallel?


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PROCEDURE


2. Short the terminals AB and find the current by connecting the ammeter

3. The load resistor is removed and source is short circuited the equivalent resistance is

measured with respect to terminal AB.

4. Value of load current is calculated theoretically and verified with practical value

5. The experimented is repeated for different values of source voltages.

INFERENCE

RESULT

Lab Performance 10

Observation 10

Viva 10

Total 30


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CIRCUIT DIAGRAM

A

AA

RPS

(0-30)V

1K

3K

2K

(0-10)mA

MC

(0-10)mA

MC

(0-10)mA

MC

OBSERVATIONS.No RPS Voltage (Volts) I(mA) I1(mA) I2(mA)


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Ex:No: Date:

VERIFICATION OF KIRCHO$Ff`s LAWS (KVL & KCL )

AIM:To verify the laws governing the electric circuits

i. Ohm`s lawii. Kirchoff`s Current Law (KCL)

iii. Kirchoff`s Voltage Law (KVL)

APPARATUS REQUIREDS.No. Name of the Apparatus Range Quantity

1 Resistors 1K 1

100 2

2 Ammeter (0-25)mA, MC 3

3 Bread board --- 1

4 DC- Regulated Power Supply (0-30)V 1

OHM`s LAW STATEMENTOhm`s law states that potential difference across the end of the conductor is

directly proportional to the current flowing through it at a constant temperature.

KIRCHOFF`s CURRENT LAW STATEMENTKirchoff`s current law states that In any electrical network the algebraic sum of the

current entering at any node is zero

KIRCHOFF`s VOLTAGE LAW STATEMENTKirchoff`s law states that the algebraic sum of the voltage around any closed path is

zero


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OHM`s LAWS.No RPS Voltage (Volts) I(Practical)mA I(Theoretical) (mA)

KIRCHOFF`s CURRENT LAWS.No Practical Theoretical

I(mA) I1(mA) I2(mA) I = I1+ I2mA

I(mA) I1(mA) I2(mA) I = I1+ I2mA


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PROCEDURE1. Connections are made as per the circuit diagram

2. For different ranges of voltages, the ammeter I, I1,I2reading was noted

3. Tabulate the readings

4. From the tabulated readings, ohm`s law, Kirchoff`s current law and Kirchoff`s

voltage law are verified.

INFERENCE


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KIRCHOFF`s VOLTAGE LAWS.No Practical Theoretical

RPSVoltage(V)

I1R1 I2R2 V=I1R1+I2R2 RPSVoltage(V)

I1R1 I2R2 V=I1R1+I2R2

CALCULATION


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Vivaquestions

1. Define energy.2. Define power.3. Define charge.4. What is meant by linear and nonlinear elements?5. What is meant by active and passive elements?6. What is meant by Unilateral and bi lateral elements?7. Define ideal voltage source.8. Define KCL9. Define KVL.10.Define Electric current.

RESULT

Lab Performance 10Observation 10

Viva 10

Total 30


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CIRCUIT DIAGRAMCase i

RPS

(0-30)V

33 18

330 RPS

(0-30)V

A (0-100)mA

MC

Case ii

RPS

(0-30)V

33 18

330

A (0-100)mA

MC

Case iii


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Ex:No: Date:

VERIFICATION OF SUPERPOSITION THEOREM

AIM:To verify the super position theorem for the given electric circuits

APPARATUS REQUIREDS.No Name of the Apparatus Range Quantity

1 DC regulated power supply (0 - 30)V, 2A 2

2 Ammeter (0-25)mA, MC 1

3 Resistors 1K 3

4. Voltmeter (0-30)V, MC 1

5 Bread Board -- 1

SUPERPOSITION THEOREM STATEMENT

The super position theorem states that the response in a linear circuit having marethan one independent source can be obtained by adding the responses caused by theseparate independent source acting alone.THEORY

Theory:The superposition theorem states that In a linear, lamped element, bilateral electric

circuit that is energized by 2 or more sources the current in any resistor is equal to thealgebraic sum of the separate current in the resistor when each source acts separately.While one source is applied, the other sources are replaced by their respective internalresistance. To replace the other sources by their respective internal resistance, the voltagesources are short-circuited and the current sources open circuited.

Consider the given electric circuit:

IL

2E

1

R1

LRE

2R


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TABULATIONS.No. Voltage Source PRACTICAL THEORY

Voltage (V) Current (mA) Voltage (V) Current (mA)

CALCULATION


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To find the current through RL, first short circuit the voltage source E2 by the internalresistance.

I'L

1

R1

LRE

2R

Let IL= current through the load while source E1acting alone.

And find current through IL= (E/(R1+RL

||R2)) * (R2/ (R2+RL))Now short circuit the voltage source E1by the internal resistance and energize the voltagesource E2

I''L

2E

R1

LR

2R

Let IL

= current through the load while source E2acting alone.And find IL

= E2/ (R2+ R1||RL) * (R1/(R1+RL))

IL = IL+ IL

PROCEDURECase i

1. Connections are mode as per circuit diagram

2. Power supplies are switched on and voltage is kept at V1and V23. The ammeter and the voltmeter readings are noted down for different voltage in

both voltage sources

Case ii1. Connections are made as per the circuit diagram

2. Voltage source V2 is short circuited

3. Voltage source V1is switched on note down ammeter and voltmeter readings for

different voltages

Case iii1. Connections are made as per the circuit diagram

2. Voltage source V1 is short circuited3. Voltage source V2is switched on note down ammeter and voltmeter readings for

different voltages


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Viva- Questions1. Define ideal current source.2. What is meant by source transformation?3. What are ideal elements?

4. Define form factor.5. Define peak factor.6. Define Ohms Law.7. State superposition theorem.8. Define ideal voltage source.9. Define ideal current source.10..What is meant by source transformation


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INFERENCE

RESULT

Lab Performance 10

Observation 10

Viva 10

Total 30


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CIRCUIT DIAGRAM

RPS

(0-30)V

330

(0-10)mA

MC

A

DRB


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Ex:No: 11 A Date:

VERIFICATION OF MAXIMUM POWER TRANSFER THEOREM

AIM:

to verify the maximum power transfer theorem for the given electric circuit.APPARATUS REQUIREDS.No Name of the Apparatus Range Quantity

1 Dc regulated power supply (0-30)V 1

2 Ammeter (0-10)mA 1

3 Source resistance 10K 1

4 Decade Resistance Box --- 1

5 Bread board --- 1

MAXIMUM POWER TRANSFER THEOREM STATEMENTMaximum power transfer theorem states that maximum power is transferred fromsource to load, when the load resistance is equal to the source resistance.

THEORYMany circuits basically consist of sources, supplying voltage, current or power to the

load. Sometimes it is necessary to transfer maximum voltage, current or power from thesource to the load. It is a fact that more voltage is delivered to the load when the loadresistance is small compared to the source resistance.

The maximum power transfer theorem states that maximum power is delivered froma source to a load when the load resistance is equal to the source resistance.

+

-

VS

RS

RL

I


71/92

TABULATION

S.No RL (K) IL (mA) PL = mW

CALCULATION


72/92

Current in the circuit is

Power delivered to the load RLis P = I2RL= VS

2RL/ (RL+RS)2

To determine the value of RLfor maximum power to be transferred to the load, the firstderivative of the above equation with respect to RLshould be equal to zero.

0222 222 LSLLSSS RRRRRRR

LS RR So, the maximum power will be transferred to the loadwhen the load resistance is equal to the source resistance.

PROCEDURE1. Connections are made as per the circuit diagram.

2. The voltage is kept constant by adjusting RPS.

3. By changing the value of RL with the help of DRB, the ammeter reading is tabulated.

4

22 2

LS

LSLLSS

RR

RRRRRV

022 LSLLS RRRRR


73/92


74/92

Vivaquestions

1. State maximum power transfer theorem.2. Steps to solve maximum power transfer Theorem3. What is a Dual Network?

4. Steps to draw a Dual Network.5. What are the limitations of Maximum power transfer theorem?6. Write some applications of maximum power transfer theorem.7. What is the condition for maximum power transfer.

INFERENCE

RESULT

Lab Performance 10

Observation 10

Viva 10

Total 30


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CIRCUIT DIAGRAM

Case i

Case ii

3K 10K

2K RPS

(0-30)VA (0-1)mA

MC


76/92

Ex:No: Date:

VERIFICATION OF RECIPROCITY THEOREMAIM:

To verify of the reciprocity theorem for the given electric circuit.APPARATUS REQUIRED:

S.No Name of the Apparatus Range Quantity

1 Dc regulated power supply (0-30)V 1

2 Ammeter (0-25)Ma, MC 1

3 Resistors 1K 2

1.5 K 1

4 Decade Resistance Box --- 1

5 Bread board --- 1

RECIPROCITY THEOREM STATEMENT

In a linear bilateral single source circuit the ratio of excitation to response is constant

when the position of excitation and response are interchanged. Here the excitation is either

a voltage source or a current source and the response in either current or voltage in a

element (R,L,C). this theorem will be satisfied only by circuits or network which does not

have dependent sources.

THEORYThe reciprocity theorem states that, In a linear, bilateral, network a voltage

source V volts in a branch gives rise to a current I in another branch, the ratio V/I is

constant when the position of V and I are interchanged.

According to this theorem if a source voltage and ammeter are interchanged, the

magnitude of the current through the ammeter will be the same. Consider a network with

two loops A & B. if an ideal voltage source Vs in loop A produces a current I in loop B, then

interchanging positions, if an ideal source in B produces the same current I in loop A. The

network is said to be Reciprocal.


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TABULATIONS.No. INPUT VOLTAGE CURRENT FOR CASE i

mA

CURRENT FOR CASE ii

mA

THEORITICAL PRACTICAL THEORITICAL PRACTICAL

CALCULATION


78/92

PROCEDURECase i

1. Connections are made as per the circuit diagram2. Set of the RPS volt for the required voltage3. Measure the corresponding current I2 also calculated it theoritically

Case ii1. Connections are made as per the circuit diagram2. Set of the RPS volt for the required voltage3. Measure the corresponding current I2 also calculated it theoritically

Result

Thus Reciprocity Theorem was verified and the values were tabulated.

Vivaquestions

.1.State reciprocity theorem

2.What are the limitations of reciprocity transfer theorem?

3.Write some applications of reciprocity theorem.4.Steps to solve reciprocitys Theorem

5. Steps to solve reciprocity Theorem6.What is a Dual Network?

7.Steps to draw a Dual Network.


79/92

Circuit Diagram

A(0-10)mA

MIAC Function

Generator

2K 50m 0.02F

Model Graph

F(Hz)

V

fr


80/92


FREQUENCY RESPONSE OF SERIES RESONANCE CIRCUIT

Aim

To design a RLC series resonant circuit and to obtain the frequency response and

resonant frequency.

Apparatus Required

SINO

Particulars Range/Rating Quantity

1 Resistors DRB 12 Inductor Inductance box 1

3 Capacitor 0.02 F 14 CRO 15 AFO 16 Connecting wires7 Bread Board

FormulaResonant frequency fr = 1

_________2 LC

Theory:

The resonance of a series RLC circuit occurs when the inductive and capacitive

reactance are equal in magnitude but cancel each other because they are 180 degrees apart

in phase. The sharp minimum in impedance which occurs is useful in tuning applications.

The sharpness of the minimum depends on the value of R and is characterized by the "Q" of

the circuit. It has a minimum of impedance Z=R at the resonant frequency and the phase

angle is equal to zero at resonance. The expression for resonant frequency is given by

LCfr

2

1

Design Procedure

Assume suitable values of R and L.Resonant frequency fr is given.

1then , C= _________

(2) 2fr2L


81/92

Tabulation

SINO

Frequency in Herzt Voltage across RV

volts

Current through thecircuitI=V/R

Amps


82/92

Procedure

1. The connections are made as per the circuit diagram.

2. A voltage of constant magnitude is set in the AFO.

3. The magnitude of voltage across the resistor is measured using CRO.

4. The procedure in step 3 is repeated for various values of frequencies and is tabulated.

5. Plot the graph for voltage vs frequency

Result:

Thus the series RLC resonant circuit was designed and the frequency response curve

was drawn and the resonant frequency was obtained.

Resonance frequency =___________________

Vivaquestions

1.What is transient?

2.Why transients occurs in electric circuits?

3.What is free and forced response?4.What is complementary function?

5.What is particular solution?6.Define time constant of RL circuit.

7.Define time constant of RC circuit.8.Define quality factor.

9.What are half power frequencies?

10.Write the characteristics of series resonance.


83/92

I

F (Hz)

Fr

Circuit Diagram

A

(0-10)mA

MI

AC Function

Generator

2K

50m 0.02F

Model graph:


84/92


FREQUENCY RESPONSE OF PARALLEL RESONANCE CIRCUITAim

To design a RLC parallel resonant circuit and to obtain the frequency response and

resonant frequency.

Apparatus Required

SI

NO

Particulars Range/Rating Quantity

1 Resistor 1K 12 Inductor 7.04 mH 23 Capacitor 0.1F 14 CRO 15 AFO 16 Connecting wires7 Bread Board

Formula

Resonant frequency fr = 1

_________2 LC

Theory:

In parallel RLC circuits the circuit behaves purely resistive at resonance. But current

supplied by source is minimum and hence called as anti- resonance. Resonance is a state in

which the inductive reactance equals the capacitive reactance (XL= XC) at a specified

frequency.

The frequency at which XL= XCis called parallel resonance and this is satisfactory

if resistances are small. Otherwise the frequency at which parallel impedance is maximum

may also be called as parallel resonant frequency.

Because inductive and capacitive reactance currents are equal and opposite in

phase, they cancel one another at parallel resonance. If a capacitor and an inductor, each

with negligible resistance, are connected in parallel and the frequency is adjusted such that

reactances are exactly equal, current will flow in the inductor and the capacitor, but the

total current will be negligible. The parallel C-L circuit will present almost infinite

impedance. The capacitor will alternately charge and discharge through the inductor.

Design Procedure

Assume suitable values of R and L Resonant frequency fr is given.


85/92

Tabulation

SI

NO

Frequency in Herzt Voltage across

RV

volts

Current through

the circuitI=V/R

Amps


86/92

1

then , C= _________(2) 2fr2L

Thus, in a parallel R-C-L, the net current flow through the circuit is at minimum because of

the high impendence presented by XLand XCin parallel.

L

CR

LCfr 1

2

1

If ratio CR/L is less than one the resonant frequency is

LCfr

2

1

Procedure:

1. The connections are made as per the circuit diagram.

2. A voltage of constant magnitude is set in the AFO.

3. The magnitude of voltage across the resistor is measured using CRO.

4. The procedure in step 3 is repeated for various values of frequencies and is tabulated.

5. Plot the graph for voltage vs frequency.

Result:

Thus the Parallel RLC resonant circuit was designed and the frequency response curve

was drawn and the resonant frequency was obtained.

Vivaquestions

1.What is anti resonance?

2.Write the characteristics of parallel resonance.

3.What is Band width and Selectivity?

4.Properties of a series RLC circuit.

5.Properties of a parallel RLC circuit.6.What is critical resistance?

7.What is critical damping.8.What is critical resistance?

9.What is natural and damped frequency?

10.What does series aiding mean?

11.What does series opposing mean?


87/92

CIRCUIT DIAGRAM:

RL CIRCUIT:

TABULATION:

S.NO. TIME CHARGING DISCHARGING

(msec) CURRENT (I) A CURRENT (I) A


88/92


TRANSIENT RESPONSE OF RC AND RL CIRCUITS FOR DC INPUTS.

AIM:

To construct RL & RC transient circuit and to draw the transient curves.

APPARATUS REQUIRED:

S.NO. NAME OF RANGE TYPE QTY.

THE

EQUIPMENT

1. RPS (0-30)V DC 1

2. Ammeter (0-10)mA MC 1

3. Voltmeter (0-10)V MC 1

4. Resistor 10 K - 3

5. Capacitor 1000 F - 1

6. Bread board - - 1

7. Connecting - Single strand As required

wires

THEORY:

Electrical devices are controlled by switches which are closed to connect supply to

the device, or opened in order to disconnect the supply to the device. The switching

operation will change the current and voltage in the device. The purely resistive devices will

allow instantaneous change in current and voltage.

An inductive device will not allow sudden change in current and capacitance device

will not allow sudden change in voltage. Hence when switching operation is performed in

inductive and capacitive devices, the current & voltage in device will take a certain time to

change from pre switching value to steady state value after switching. This phenomenon is

known as transient. The study of switching condition in the circuit is called transient

analysis.The state of the circuit from instant of switching to attainment of steady state is

called transient state. The time duration from the instant of switching till the steady state is

called transient period. The current & voltage of circuit elements during transient period is

called transient response.


89/92

MODEL CALCULATION & ANALYSIS:

FORMULA:

Time constant of RC circuit = RC

MODEL GRAPH:

CIRCUIT DIAGRAM:

RC CIRCUIT:

MODEL GRAPH:

CHARGING DISCHARGING

CHARGING DISCHARGING


90/92

PROCEDURE:

Connections are made as per the circuit diagram.

Before switching ON the power supply the switch S should be in off position

Now switch ON the power supply and change the switch to ON position.

The voltage is gradually increased and note down the reading of ammeter and

voltmeter for each time duration in RC.In RL circuit measure the Ammeter reading.

Tabulate the readings and draw the graph of Vc(t)Vs t


91/92

TABULATION:CHARGING:

S.NO. TIME VOLTAGE CURRENT

(msec) ACROSS C THROUGH

(volts) C

(mA)


TABULATION:

S.NO. TIME VOLTAGE CURRENT

(msec) ACROSS C THROUGH

(volts) C

(mA)



92/92

RESULT:

Thus the transient response of RL & RC circuit for DC input was verified.

circuits and devices lab manual

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