EVM Full Report_sghadei

MINI PROJECT ‘10 EVM

DEPT OF ELEC & COMMN CUSAT santosh ghadei

1

ACKNOWLEDGEMENT

Dreams never shape to reality unless a lot of effort and hard work is put into

it. And no effort bears fruit in the absence of support and guidance. A lot of

effort and hard work has been put into this project in course of the three

months taken to complete it. It has been strenuous but very satisfying

experience.

At the outset, we thank God almighty for making our endeavour a success. We

also express our gratitude to MR. MANOJ V. J. , Head of the Department

for providing us with adequate facilities, ways and means by which we were

able to complete this project.We express our sincere gratitude to our Project

Guide MRS. VEENA C. BHASKAR and project co-ordinator Miss.

Prabha Raj C. and Miss Preeja P. K. , Electronics & Communication

Engineering Department for her constant support and valuable suggestions

without which the successful completion of this project would not have been

possible.

We express our immense pleasure and thankfulness to all the teachers and staff

of the Department of Electronics & Communication, CUSAT for their

cooperation and support. And at the end we would like to extend our heartiest

thanks to our family members, seniors and class mates, who always supported

us throughout and lend their helping hand in making this project a successful

one.



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Electronic

Voting

Machine

Mini project



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CONTENT

1. Abstract……… ………… ……… 04

2. Introduction… …… ……… ……05

3. Block diagram… …… ……… …06

4. Components required … … … 07

5. Circuit diagram… ……… … …24

6. Working Of the Instrument … 27

7. Application ……… …… ………29

8. Soldering ………… ……………30

9. Waveform ………………………33

10. Result ……………………………35

11. Conclusion …… ……… ………36

12. Advantage and Disadvantage 37

13. Reference ………………………38

14. Datasheet ………………………39



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ABSTRACT

India is the largest democracy of the world . People’s active participation in the

formation of the government is an important aspect of a democratic

government. This is ensured by elections. Conducting free and fair elections in

a populous country like India is an uphill task. It’s a challenge to conduct

elections for selection of candidates to represent the people of the country at

different levels. Even more important is the timely declaration of results. This

is necessary to bring stability in the governance and steady economic growth

of the nation .

Till now we have been using the paper and ballot system for conducting. The

loop holes in this traditional system are gradually widening .Its more

susceptible to booth capturing and result manipulation. Even more tedious is

the task of counting the votes and declaring the results.

An ELECTRONIC VOTING MACHINE is an answer to all these problems.

It’s a technological masterpiece. Many countries worldover have shown

their interest in learning the mechanism behind this simple yet powerful

machine. Its got a very simple interface,its tamperproof, prevents bogus voting

and it has helped in getting rid of the time consuming task of counting .



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INTRODUCTION

EVM stands for Electronics Voting Machine. It’s a lot different from the

traditional ballot paper system both in terms of mechanism and performance.

Its USP is its simple user interface. Even a person who never got a chance to

go to schools can use it without much difficulty. The front panel shows all the

candidates standing for the election along with their party symbols. There is a

button corresponding to each of the candidates. To cast a vote just press the

button beside to the candidate. A successful vote is indicated by a green light

and a short beep.

There is a dedicated counter for each of the candidate ,which is placed inside.

With each vote the counter corresponding to the candidate increases and is

displayed through a LCD screen. This arrangement is kept under lock. After

the election’s over the polling officer can open the lock and view the votes and

declare the result.



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BLOCK DIAGRAM

CANDIDATE 1

CANDIDATE 2

Prevent bogus voting + visual indicators

XOR

gates

Control

flip flop

LCD

SCREEN

COUNTER

LCD

SCREEN

COUNTER

Candidate 1 VOTE COUNTING Candidate 2

LED



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COMPONENTS REQUIRED

Resistors

7404 IC

7408 IC

7447 IC

7473 IC

7490 IC

FND 507 : Seven segment display

LEDs

Beeper



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Function :-

Resistors restrict the flow of electric current, for example a resistor is placed in

series with a light-emitting diode (LED) to limit the current passing through

the LED.

Example: Circuit symbol:

Connecting and soldering :-

Resistors may be connected either way round. They are not damaged by heat

when soldering.

Resistor values – The resistor colour

code :- Resistance is measured in ohms, the symbol for ohm is an omega Ω .

1 Ω is quite small so resistor values are often given in k Ω and M Ω.

1 k Ω = 1000 Ω 1 M Ω = 1000000 Ω.

Resistor values are normally shown using coloured bands. Each colour

represents a number as shown in the table. Most resistors have 4 bands:

The first band gives the first digit.

The second band gives the second digit.

The third band indicates the number of zeros.

The fourth band is used to shows the tolerance (precision) of the

resistor.

RESISTOR



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This resistor has red (2), violet (7), yellow (4 zeros) and gold bands.

So its value is 270000 Ω = 270 k Ω.

On circuit diagrams the Ω is usually omitted and the value is written 270K.

The Resistor

Colour Code

Colour Number

Black 0

Brown 1

Red 2

Orange 3

Yellow 4

Green 5

Blue 6

Violet 7

Grey 8

White 9



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220 Ω RESISTOR :

Typically 220 ohm ,1/4 watt resistor can be used with various circuit.The

colour band of the resistor is Red, Red, Brown, Gold.

Type:Carbon film resistor

Tolerence:5%

Size:1/4watt

Value:220Ω

270Ω RESISTOR :

Typically 270 Ω,1/4watt resistor can be used with various circuit.The colour

band is Red,Purple,Brown,Gold.

Type:Carbon film resistor

Tolerence:5%

Size:1/4 watt

Value:270Ω



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IC 7404

IC 7404 is a NOT gate, also called an inverter has only one input and, of

course , only one output.

NOT GATE Logic-Rules:

The output is the inverse of the input, in otherwords if the input is HIGH then

the out put is LOW and if the input is LOW the output is HIGH.

IC' S



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IC7408

IC 7408 is an AND gates has two or more input but only one output .It is also

called an all or nothing gate.

AND GATE Logic Rules:

The output assumes the logic HIGH state , only when each of its input is at

logic HIGH state.



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IC 7486

XOR stands for exclusive OR. XOR gate compares two values and if they are

So Y = A B. It is also called an anti-coincidence or inequality detector.

XOR GATE Logic Rule:

An X-OR gate produces an active HIGH output only when the input are not

equal.The output of an X-OR gate is the modulo sum of its two input.



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IC 7490

The 7490 is a decade counter (mod-10) which consists of four master- slave

flip-flops internally connected to provides a divide-by-2 and a divide -by-

5counter.Gates direct-reset line are provided to inhibit count input to either a

logic 0 or to a BCD count

When used as a BCD counter ,the B input must be externally connected to the

QA output. The A input receive the incoming count, and a count secquence is

obtained to in accordance with the BCD count output.two gates input are

provided to reset the counter to 0; in addition ,two more input are also

nprovided to reset the counter to a BCD count of 9 for the 9’s compement

decimal applications.



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Function :-

LEDs emit light when an electric current passes through them.

Example: Circuit symbol:

Connecting and soldering :-

LEDs must be connected the correct way round, the diagram

may be labelled a or + for anode and k or - for cathode (yes, it

really is k, not c, for cathode!). The cathode is the short lead

and there may be a slight flat on the body of round LEDs. If you can see inside

the LED the cathode is the larger electrode (but this is not an official

identification method).

LEDs can be damaged by heat when soldering, but the risk is small unless you

are very slow. No special precautions are needed for soldering most LEDs.

Colours of LEDs :-

LEDs are available in red, orange,

amber, yellow, green, blue and white.

Blue and white LEDs are much more

expensive than the other colours.The

colour of an LED is determined by the

semiconductor material, not by the

colouring of the 'package' (the plastic body). LEDs of all colours are available

in uncoloured packages which may be diffused (milky) or clear (often

LIGHT EMITTING DIODE



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described as 'water clear'). The coloured packages are also available as diffused

(the standard type) or transparent

COLOUR WAVELENGTH (nm) VOLTAGES (V) MATERIALS

Red

610 <ʎ< 760

1.63 <v<2.03

GaAsP, AlGaInP,

GaP

Green 500< ʎ<570 1.9<v<4.0 InGaN , GaP

AlGaInP

Symbol :-

Anode cathode



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A seven-segment display (abbreviation: "7-seg(ment) display"), less

commonly known as a seven-segment indicator, is a form of electronic

Display device for displaying decimal numerals that is an alternative to the

more complex dot-matrix displays. Seven-segment displays are widely used in

digital clocks electronic meteters, and other electronic devices for displaying

numerical information.

In a simple LED package, each LED is typically connected with one terminal

to its own pin on the outside of the package and the other LED terminal

connected in common with all other LEDs in the device and brought out to a

shared pin. This shared pin will then make up all of the cathodes (negative

terminals) OR all of the anodes (positive terminals) of the LEDs in the device;

and so will be either a "CommonCathode" or "Common Anode" device

depending how it is constructed.

7 - SEGMENT DISPLAY



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The 8-pin 555 timer is one of the most

useful Integrated Circuits (ICs) . It is also

one of the cheapest and most-rugged

chips.The most common types of outputs

can be categorized by the following .

Astable - producing a square wave

Monostable - producing a single pulse

when triggered

Bistable - a simple memory which can be

set and reset

Astable Operation :-

The capacitor C charges via R1 and R2 and when the voltage on the capacitor

reaches 2/3 of the supply, pin 6 detects this and pin 7 connects to 0v. The

capacitor discharges through R2 until its voltage is 1/3 of the supply and pin 2

detects this and turns off pin 7 to repeat the cycle.

The top resistor is included to prevent pin 7 being damaged as it shorts to 0v

when pin 6 detects 2/3 rail voltage. Its resistance is small compared to R2 and

does not come into the timing of the oscillator

555 TIMER



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Charging and Discharging Times :-

T1 = 0.693 (R1 +R2) C

T2 = 0.693*R2*C2

Features Of 555 Timer :- The 555 Timer is a highly stable & inexpensive device for generating

accurate time delay or oscillation.

It can provide time delays ranging from microseconds to hours.

It can be used with power supply voltage ranging from +5V to +18V.

It is compatible with both TTL & CMOS logic circuits.

It has very high temperature



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Features :-

RATED FREQUENCY : 3,500Hz

OPERATING VOLTAGE : 3-28Vdc

CURRENT CONSUPTION : 6Ma@12Vdc

SOUND PRESSURE LEVEL(30cm) : 88Db@12vdc

KINGSTAGE BUZZER : KPE-272

DIMENSIONS : 32 mm Di

PIN SPACING : 17.8 mm

PIEZO BUZZER



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Function :-

Transistors amplify current for example they can be used to amplify the small

output current from a logic IC so that it can operate a lamp, relay or other high

current device. In many circuits a resistor is used to convert the changing

current to a changing voltage, so the transistor is being used to amplify voltage.

A transistor may be used as a switch (either fully on with maximum current, or

fully off with no current) and as an amplifier (always partly on).The amount of

current amplification is called the current gain, symbol hFE.

For further information please see the Transistor Circuit page.

Types of transistor :-

There are two types of standard

transistors, NPN and PNP, with different circuit

symbols. The letters refer to the layers of

semiconductor material used to make the transistor.

Most transistors used today are NPN because this is

the easiest type to make from silicon. If you are new to

electronics it is best to start by learning how to use

NPN transistors.

The leads are labelled base (B), collector (C) and emitter (E).

These terms refer to the internal operation of a transistor but they are not much

help in understanding how a transistor is used, so just treat them as labels!

A Darlington pair is two transistors connected together to give a very high

current gain.In addition to standard (bipolar junction) transistors, there

are field-effect transistors which are usually referred to as FETs. They have

different circuit symbols and properties and they are not (yet) covered by this

page.

Transistor circuit symbols

TRANSISTOR



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Function :-

Capacitors store electric charge. They are used with resistors in timing circuit

because it takes time for a capacitor to fill with charge. They are used

to smooth varying DC supplies by acting as a reservoir of charge. They are

also used in filter circuits because capacitors easily pass AC (changing) signals

but they block DC (constant) signals.

There are many types of capacitor but they can be split into two

groups, polarised and unpolarised. Each group has its own circuit symbol.

Polarised capacitors (large values, 1µF +)

Examples:

Circuit symbol:

Electrolytic Capacitors

Electrolytic capacitors are polarised and they must be connected the correct

way round, at least one of their leads will be marked + or -. They are not

damaged by heat when soldering.

There are two designs of electrolytic capacitors; axial where the leads are

attached to each end (220µF in picture) and radial where both leads are at the

same end (10µF in picture). Radial capacitors tend to be a little smaller and

they stand upright on the circuit board.

CAPACITORS



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It is easy to find the value of electrolytic capacitors because they are clearly

printed with their capacitance and voltage rating. The voltage rating can be

quite low (6V for example) and it should always be checked when selecting an

electrolytic capacitor. If the project parts list does not specify a voltage, choose

a capacitor with a rating which is greater than the project's power supply

voltage. 25V is a sensible minimum for most battery circuits.

Unpolarised capacitors (small values,

up to 1µF) :-

Examples: Circuit symbol:

Small value capacitors are unpolarised and may be connected either way

round. They are not damaged by heat when soldering, except for one unusual

type (polystyrene). They have high voltage ratings of at least 50V, usually

250V or so. It can be difficult to find the values of these small capacitors

because there are many types of them and several different labelling systems!

Many small value capacitors have their value printed but without

a multiplier, so you need to use experience to work out what the

multiplier should be!



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CIRCUIT DIAGRAM



25



26

CIRCUIT DIAGRAM ( improved part)

The supply to this circuit will be from the green LED . So that on successful

casting of vote we can hear the beep.



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WORKING OF THE INSTRUMENT

When no switch is pressed the inverter gets a input of + 5 V ,and the

corresponding output is high. When a switch is pressed we get a high at the

corresponding inverter output and at the corresponding AND gate input. For

making the vote to count for the respective candidate ,we need another high

input . This we get from the JK flip flop (IC 7473 ).

Exclusive OR gate (IC7486) prevents the voter from pressing more than one

button i.e. trying to vote for more than one candidate. IC 7473 locks itself

once a vote has been cast and thus prevents multiple votes by a person. With

casting of the vote, both the Green and Red LEDs are lightened

simultaneously. The green LED is an indication for the voter that a successful

vote has been cast. And the Red LED is for the polling officer ,it indicates him

that he has to reset the flip flop so that the next voter can cast his vote.

Pin 13 of IC7473 goes ‘low’ as soon as a ‘valid’ vote is recorded. This in turn

blocks all AND gates to avoid further counting of votes, till the officer in

charge resets the system through switch S5 at his table. Resetting of S7 should

be done only when the voter has come out of the both after casting his vote.

The counting of votes is carried out by the counters wired using IC 7490.

Only ‘unit’ and ‘ten’ positions are implemented in this circuit. Depending on

the number of voters expected , the hundred and thousandth position can be

wired. The votes corresponding to S1-S4 are counted by counter C1-C4

respectively. Switch S6 must be kept under a lock and key arrangement. It



28

should be reset before the voting starts and should not be disturbed there after

till the voting is over and the results have been declared.

Counters will store the digits as far as supply continues without failure. So an

uninterrupted + 5V supply derived from a battery is advisable.



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APPLICATIONS

1. It is used in general elections for choosing candidates to represent

people at various stages.

2. It can be used in school ,college student union elections.

3. It can be used to find the general opinion of people on various issues.

4. Anywhere where majority opinion is to be found out.



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SOLDERING

Soldering iron :-

The iron consist of an insulating handle connected via a metal shank to the bit.

The function of bit is to :

1. Store and deliver molten solder and flux.

2. Store heat and pass it to the compounds.

3. Remove extra solder from joints.

Soldering bit is made of copper because it has good heat capacity and thermal

conductivity.Some iron have thermostatic control to keep the temperature of

bit constant, various wattage such as 10 w 25 w,35 w, 60 w, 100 w are

available.

Soldering flux :-

Flux is a medium used to improve the degree of wetting. The desirable

property of flux are :



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1. It should provide a liquid cover for the material and avoid air gap to the

soldering temperature.

2. It should dissolve any oxide on metal surface.

3. It should be easily displaced from the metal by molten soldering

operation.

4. Residue should be removable after soldering operation.

The flux consists of Zinc Chloride or olive oil with active such as glycol acid,

Ammonium chloride and organic acids. By adding activates , flow and activity

is increased without affecting corrosion.

Solder :-

The three grades of solder generally used for soldering are 40/60 , 50/50 ,60/40

,etc of tin and lead respectively. The 60/40 w solder has high cost but it melts

at lowest temperature, flow more freely, takes less time to harden and

generally makes it easier to do good soldering job. Solder is generally available

in the form of wire. Flux is also incorporated in solder wire itself. In such case

no extra flux is necessary.



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Soldering with iron :-

The surface to be soldered must be cleaned and fluxed . the soldering iron is

switched on and allowed to attain soldering temperature . the solder in the form

of wire is applied near the component and heated with iron. The surface to the

solder are fitted , iron is removed and joints are cooled without any

disturbance.

The following are the advantage of soldering :

1. A good soldering provides a good permanent resistance path .

2. Makes good electrical link between PCB and leads of component.

3. Retain the required strength with temperature variation.



33

WAVEFORM

A) Waveform of edge-triggered J-K flip-flop

CLK

J Input

K

Q

Output

B) Waveform of NOT gate

A Input

X Output



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C) Waveform of AND gates

Input

A

B

X

Output

D) Waveform of OR gates

A

Input

B

Output

X



35

RESULT

The Electronic Voting Machine was assembled successfully

and the desired result was obtained.



36

CONCLUSION

The Electronic voting machine helped the voter

to cast his vote in a hassle free manner and for the poling officer it

proved to be a more convenient way to count the votes and declare

the result.



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ADVANTAGE AND DISADVANTAGE

Advantage :-

1. Simple user interface.

2. Less cost

3. Quick results

4. Fair elections

5. Tamperproof

Disadvantage :-

1. Limited no. of candidates.

2. More candidates mean implies complicated circuit.



38

REFERENCES

1. Fundamentals of Digital Circuit By ANAND KUMAR

2. ELECTRONICS FOR YOU

3. Electronics Portal – WIKIPEDIA

4. www.alldatasheet.com

5. www.datasheetcatalog.com

6. Electronics Lab Manual by K. A. Navas

7. Internet search engines – www.google.com

http://www.alldatasheet.com/

http://www.datasheetcatalog.com/

http://www.google.com/



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DATASHEET

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EVM Full Report_sghadei