Download laser based intruder alarm

LASER BASED INTRUDER ALARM
Page | 1
A
Project Report
On
LASER BASED INTUDER ALARM SYSTEM
In partial fulfillment of requirements for the degree of Diploma
Engineering in EC Engineering
Submitted By:
Under the Guidance of
1. Parth R. Varasada -106030311019
2. Chirag J. Zala
Mr. J.B.Ratnottar
-106030311015
3. Bhavesh B. Bhalu -106030311058
DEPARTMENT OF ELECTRONICS & COMMUNICATION ENGINEERING
ATMIYA INSTITUTE OF TECHNOLOGY AND SCIENCE FOR DIPLOMA
STUDIES, RAJKOT- 360005.
[2012 – 2013]
Page | 2
CERTIFICATE
This is to certify that the project entitled “Laser Based Intruder Alarm” has been carried
out by the team under my guidance in partial fulfillment of the Diploma of Engineering in
Electronics & Communication in GTU during the academic year 2012-2013 (Semester-5).
Team:
1. Parth R. Varasada
2. Chirag J. Zala
3. Bhavesh R. Bhalu
Date:
Place:
Guide
Head, EC Department
(Mr. J. B. Ratnottar)
(Mr. D .M .Jethloja)
Principle
(Mr. G. C. Joshi)
External guide
(Mr. G. R. Patel)
Page | 3
ABSTRACT
In 21st century security is most important parameter for industries because the
competition of best production between companies. The working principle of this project is
based on two circuits one is Transmitter and other Receiver.
Intruder means unauthorized person or trespasser, which means the person who has no
permission to enter in the restricted area.
We can use this laser Based Intruder Alarm conveniently at the entrance of a hall or any
other similar location to protect from unauthorized access and when desired.
The transmitter circuit consists of voltage regulated IC-7805 and laser diode driven by a
9v battery.
The circuit of receiver is consist of voltage regulated IC-7805, IC LM-356, timer IC-555,
photo transistor L14F1 and buzzer
Page | 4
List of figure
Figure
Page No.
1.1 Wired Systems
5
1.2 Wire free Systems
6
1.3 Detection Devices
7
1.4 The Door Contact (Magnetic Reed Switch)
8
1.5 The Panic Button (PA Button)
8
1.6 laser based security system
9
1.7 Transmitter circuit
10
1.8 Receiver Circuit
10
3.1 Laser Pointer
12
3.2 Photo transistor
13
5.1 Block diagram of transmitter
15
5.2 Block diagram of receiver
15
5.3 Complete block diagram of project
16
6.1 Transmitter circuit
18
6.2 Circuit of receiver
19
7.1 Pin Configuration of IC 7805
21
7.2 Capacitors
22
7.3 Construction of Capacitors
24
7.4 Resistors
25
7.5 Diode
27
7.6 Bc-548
27
7.7 Transistor
29
7.8 Symbol of Transistor
29
7.9 Homo junction planner photo- Transistor
30
7.10 Hetro junction structure of photo- Transistor
31
7.11 Photo- Transistor
31
7.12 symbol of photo- Transistor
33
Page | 5
7.13 Package of IC LM 386
34
7.14 Pin Configuration of IC LM 386
35
7.15 Package of 555
37
7.16 Pin Configuration of IC timer IC 555
38
7.17 laser diode
39
7.18 Buzzer
43
8.1 Transmitter circuit
45
8.2 Receiver Circuit
46
10.1 flow chart of project
49
Page | 6
List of table
Table
Page no.
6.1 component of transmitter
18
6.2 component of receiver
19
7.1 absolute maximum ratting of 7805
21
7.2 absolute maximum ratting of LM-386
36
7.3 absolute maximum ratting of 555
39
Page | 7
Chapter-1
Introduction
1.1 What is an “Intruder”?
Intruder means, “One who enters without right, a trespasser”. In simple language “A
person who enters a private residence or place of business with the intention to perform a
criminal act like: burglary etc.”
1.2 What is Intruder Alarm System?
“It is any system designed to detect and signal the presence, entry or attempted entry of an
intruder into an alarmed area.”
That means in simple language, “It is system to protect ours private property like: home,
office, business place, banks, shopping malls etc. from trespasser.”
1.3 Types of “Intruder Systems”
Wired Systems
Wire free Systems
Detection Devices
The Door Contact (Magnetic Reed Switch)
The Panic Button (PA Button)
LASER-BASED INTRUDER ALARM
1.3.1 Wired Systems
Hardwired intruder alarm systems are those that have the devices wired directly to the
control panel. These alarm systems are suitable for both the home and commercial properties.
Page | 8
Figure 1.1 wired system
1.3.2 Wire free Systems:If we don't want use cables in our property, or it is impractical to fit a conventional hard
wired system, then consider installing a wire free intruder alarm system.
Page | 9
Fig.1.2 Wire free system
1.3.3 Detection Devices:The Passive Infra-Red Sensor Detectors are an invaluable asset to any alarm system as
they detect movement or heat by looking at the room in infra-red.
Fig.1.3 Detection device
1.3.4The Door Contact (Magnetic Reed Switch):Page | 10
Commonly referred to as a door contact, but known in the trade as an MRS (Magnetic
Reed Switch), this device simply lets the alarm control panel know if a door, shutter or window
is open or closed.
Fig1.4 Door contact
1.3.5 The Panic Button (PA Button):Locations for these hardwired devices might be by the front door, or within reach of your
bed.
Page | 11
Fig 1.5 Panic button
1.3.6 LASER-BASED INTRUDER ALARM:You can use this laser-based intruder alarm conveniently at the entrance of a hall or any
other similar location to protect the same from unauthorized access as and when we desired.
Its range can be extended further to protect the perimeter of a building from unauthorized
intrusion by using a cascade arrangement of multiple alarms.
Page | 12
Figure 1.6 laser based security system
The circuit consists of a transmitter and a receiver. The transmitter circuit is as shown in
figure 1.5 and receiver circuit is as shown in figure 1.6.
Page | 13
Figure 1.7 Transmitter circuit
Figure 1.8 Receiver circuit
Chapter-2
Problem Definition
Page | 14
2. Problem definition
To save products, precious things and machinery from thief.
2.1 Detailed problem definition
In this world we live it is era of competition. We here from many companies that their new
invention and some product form their store room are theft.
2.2 What is need of this alarm system?
Alarm is a type of security equipment that can be used to safeguard homes and property.
If we love our home then buying burglar alarm should be our first priority when moving to a new
home. Burglar crimes are continually rising with each passing day. Many have lost their homes
and families through violent burglaries in many countries today. Some have lost what they
considered precious and valuable to them. Things such as jewelry, vehicles, and clothes are huge
investments to many.
During the olden days a watchman would be hired to take care of property and offer
needed security in the home. Some homes also had fierce dogs that would be let out only at
night. The two were supposed to provide security to our belongings even in the absence of the
owner .However, hiring a watchman was not an effective method since most of them would be
killed in the line of duty. Sometimes dogs would attack even visitors while some watchmen
looted property. This led to the development of alarm equipment’s
2.3 Project scope
We hope over small try to solve the problem of Universal Techno Cast industry will help
them to protect their equipment and products from the thief. It can also use to provide security to
the college campus and jewelry shop.
Chapter 3
Page | 15
Project Plan
3. Project plan
So the problem can be solved by the sense the presence of the person or anything else
which is harm full for our industry, shop, home or our private property. Due to buzzer we are
informed that someone entering into our private property. So we take step to prevent the person.
3.1 To sense the presence of the person
To sense the person we use this alarm system. This system is consists of a high intensity
light source and a light detecting device. Here we used laser light as light source and
phototransistor as the light detecting device.
Fig. 3.1 Laser Diode
Page | 16
Fig. 3.2 Phototransistor
3.2 To indicate through the buzzer
As the laser cut the buzzer ring. So the security guards reach the storage room.
Page | 17
Chapter:4
Feasibility
4.1 Financial feasibility
The resources used in this project are quite feasible financially.
Components list:

Resisters

Diode

Capacitor

Transistor

Buzzer

Laser pointer/light

Photo transistor
The list of components given above shows that all the components are cheap and feasible.
The company will not have any problem in using this simple project circuit.
4.2 Resource feasibility
All the resources used in this project are easily available. The laser diode is difficult to
find but it can be easily available from the old and chip laser light toys. So we can easily attach
them to the circuit. We can mount any component
4.3 Technical feasibility
After I gave my idea to the industry person, the industry person told that my idea was
quite feasible technically and promised to try it on his factory area.
So when we visited the industry they give us the information about the their area which
they want to cover. Main person of the company is very friendly with us.
Page | 18
Chapter 5
Block Diagram of the project
5. Block Diagram of the project
Block diagram of complete project of the laser based intruder alarm system consist of a
transmitter and receiver.
Block diagram of transmitter is as shown in figure 5.1. And block diagram of receiver is
as shown in figure 5.2.
Supply voltage
Voltage
regulated IC
Laser pointer
Figure 5.1 Block diagram of transmitter
Supply voltage
Voltage
regulated IC
Photo
Transistor
Buzzer
IC 555
IC LM386
Figure 5.2: Block Diagram Of The Receiver
Page | 19
Complete block diagram of the laser based intruder alarm system is as shown in figure 5.3.
Supply voltage
Supply voltage
Buzzer
Voltage
regulated IC
Laser pointer
Voltage
regulated IC
IC 555
Photo
Transistor
Transistor
BC548
IC LM386
Figure 5.3 Complete block diagram of the laser based intruder alarm system
5.1 Description of block diagram
As shown in above block diagram in first block of the transmitter and the receiver supply
voltage given to the voltage regulator IC. It gives regulated voltage to operate the next stage of
both the transmitter and receiver.
Output of voltage regulated IC is given to the laser pointer in transmitter. So when supply
is given to the laser pointer it is on and high intensity and focused light is produced from the
laser diode. This light is focused on the phototransistor of the receiver.
Page | 20
Due to light fall on the phototransistor, it will on so the voltage passed through it. Voltage
is now given to the input of the IC LM386. We use here IC as comparator. So output of IC is
given to the transistor BC548.
So due to input given to the transistor it will on so due to this transistor grounds all the
current. So buzzer does not sound. When light cut then transistor will off so IC555 triggered and
cause of it generates the voltage which makes buzzer on.
Page | 21
Chapter 6
Block wise explanation
6.1 Block diagram of transmitter circuit
Figure 6.1 transmitter circuit
The transmitter circuit generates light beam with the help of the laser diode\laser pointer.
This laser light is focused and of the high intensity. This light now focused on the receiver of the
security system. In above figure component used are shown with the laser diode
6.1.1 List of components
Table 6.1 List of components of transmitter
Sr.
Component
Quantity
No.
Name
1
9v DC Battery
1
2
On/Off switch
1
3
Capacitor
2
4
IC 7805(voltage regulator)
1
5
Laser diode
1
6
Resistor
1
Page | 22
6.2 Circuit diagram of receiver
Figure 6.2 Receiver circuit
Receiver circuit consist of the IC 7805, IC LM356, IC555, Photo transistor L14F1 and a
Buzzer. Photo transistor is used to detect the light focused on it. So due to light focuses’ on it , it
will generates on and output of this photo diode is given to the LM356. LM356 is used as
comparator and give voltage in its pin no. 5. This voltage is enough to on the transistor BC548.
So transistor ground the current from the collector. So no voltage is present at the pin bo 2 of the
IC555. So it gives output 0v. So buzzer remains off.
List of components
Table 6.2. List of components of receiver
Sr.
Component
Quantity
No
Name
1
9v DC battery
1
2
BC-548
1
3
IC-7805
1
4
Resistor
7
5
Diode
1
6
Photo transistor
1
7
Capacitor
7
8
IC-555
1
9
Buzzer
1
Page | 23
Chapter 7
Components detail
7.1 List of component used in project
(1) IC 7805
(2) Capacitor
(3) Resistor
(4) Diode
(5) Transistor BC548
(6) Photo Transistor
(7) IC LM386
(8) IC 555
(9) Laser Diode\Pointer
(10) Buzzer
This all component are use in to section, one is transmitter and other is receiver.
7.2 Details of component use in project
7.2.1 Detail of IC 7805
Generally IC 7805 is regulated voltage IC. It gives exact 5v in the output. The MC78XX
series of three terminal positive regulators are available in theTO-220/D-PAK package and with
several fixed output voltages, making them useful in a wide range of applications.
Each type employs internal current limiting, thermal shut down and safe operating area
protection, making it essentially indestructible. If adequate heat sinking is provided, they can
deliver over 1A output current.
Although designed primarily as fixed voltage regulators, these devices can be used with
external components to obtain adjustable voltages and currents. Our project use 7805 is of TO220 package of this IC. Its operating voltage range is from 5v-18v.
Figure of IC 7805 is as shown in figure 7.1. In this figure both packages TO-220 and
D-package are shown.
Page | 24
Figure 7.1 Packages of IC 7805
Features
• Output Current up to 1A
• Output Voltages of 5, 6, 8, 9, 10, 12, 15, 18, 24V
• Thermal Overload Protection
• Short Circuit Protection
• Output Transistor Safe Operating Area Protection
Table 7.1 Absolute maximum ratings of 7805
Page | 25
7.2.2 Details of Capacitor
Figure 7.2 Capacitor
A capacitor (formerly known as condenser) is a passive two-terminal electrical
component used to store energy in an electric field. The forms of practical capacitors vary
widely, but all contain at least two electrical conductors separated by a dielectric (insulator); for
example, one common construction consists of metal foils separated by a thin layer of insulating
film. Capacitors are widely used as parts of electrical circuits in many common electrical
devices.
When there is a potential difference (voltage) across the conductors, a static electric field
develops across the dielectric, causing positive charge to collect on one plate and negative charge
on the other plate. Energy is stored in the electrostatic field. An ideal capacitor is characterized
by a single constant value, capacitance, measured in farads. This is the ratio of the electric charge
on each conductor to the potential difference between them.
The capacitance is greatest when there is a narrow separation between large areas of
conductor; hence capacitor conductors are often called "plates," referring to an early means of
construction. In practice, the dielectric between the plates passes a small amount of leakage
Page | 26
current and also has an electric field strength limit, resulting in a breakdown voltage, while the
conductors and leads introduce an undesired inductance and resistance. Capacitors are widely
used in electronic circuits for blocking direct current while allowing alternating current to pass,
in filter networks, for smoothing the output of power supplies, in the resonant circuits that tune
radios to particular frequencies and for many other purposes.
The simplest capacitor consists of two parallel conductive plates separated by a dielectric
with permittivity ε (such as air). The model may also be used to make qualitative predictions for
other device geometries. The plates are considered to extend uniformly over an area A and a
charge density ±ρ = ±Q/A exists on their surface. Assuming that the width of the plates is much
greater than their separation d, the electric field near the centre of the device will be uniform with
the magnitude E = ρ/ε. The voltage is defined as the line integral of the electric field between the
plates. Solving this for C = Q/V reveals that capacitance increases with area and decreases with
separation
.
The capacitance is therefore greatest in devices made from materials with a high
permittivity, large plate area, and small distance between plates.
We see that the maximum energy is a function of dielectric volume, permittivity, and
dielectric strength per distance. So increasing the plate area while decreasing the separation
between the plates while maintaining the same volume has no change on the amount of energy
the capacitor can store. Care must be taken when increasing the plate separation so that the above
assumption of the distance between plates being much smaller than the area of the plates is still
valid for these equations to be accurate.
Page | 27
Figure 7.3 Construction of capacitor
7.2.3 Resistor
A linear resistor is a linear, passive two-terminal electrical component that implements
electrical resistance as a circuit element. The current through a resistor is in direct proportion to
the voltage across the resistor's terminals. Thus, the ratio of the voltage applied across a resistor's
terminals to the intensity of current through the circuit is called resistance. This relation is
represented by Ohm's law:
Resistors are common elements of electrical networks and electronic circuits and are
ubiquitous in most electronic equipment. Practical resistors can be made of various compounds
and films, as well as resistance wire (wire made of a high-resistivity alloy, such as nickelchrome). Resistors are also implemented within integrated circuits, particularly analog devices,
and can also be integrated into hybrid and printed circuits.
The electrical functionality of a resistor is specified by its resistance: common
commercial resistors are manufactured over a range of more than nine orders of magnitude.
When specifying that resistance in an electronic design, the required precision of the resistance
may require attention to the manufacturing tolerance of the chosen resistor, according to its
specific application. The temperature coefficient of the resistance may also be of concern in
some precision applications. Practical resistors are also specified as having a maximum power
rating which must exceed the anticipated power dissipation of that resistor in a particular circuit:
this is mainly of concern in power electronics applications. Resistors with higher power ratings
Page | 28
are physically larger and may require heat sinks. In a high-voltage circuit, attention must
sometimes be paid to the rated maximum working voltage of the resistor.
Practical resistors have a series inductance and a small parallel capacitance; these
specifications can be important in high-frequency applications. In a low-noise amplifier or preamp, the noise characteristics of a resistor may be an issue. The unwanted inductance, excess
noise, and temperature coefficient are mainly dependent on the technology used in
manufacturing the resistor. They are not normally specified individually for a particular family of
resistors manufactured using a particular technology. A family of discrete resistors is also
characterized according to its form factor, that is, the size of the device and the position of its
leads (or terminals) which is relevant in the practical manufacturing of circuits using them.
Figure 7.4 Resistor
7.2.4 Diode
In electronics, a diode is a type of two-terminal electronic component with nonlinear
resistance and conductance (i.e., a nonlinear current–voltage characteristic), distinguishing it
from components such as two-terminal linear resistors which obey Ohm's law. A semiconductor
diode, the most common type today, is a crystalline piece of semiconductor material connected
Page | 29
to two electrical terminals. A vacuum tube diode (now rarely used except in some high-power
technologies) is a vacuum tube with two electrodes: a plate and a cathode.
The most common function of a diode is to allow an electric current to pass in one
direction (called the diode's forward direction), while blocking current in the opposite direction
(the reverse direction). Thus, the diode can be thought of as an electronic version of a check
valve. This unidirectional behavior is called rectification, and is used to convert alternating
current to direct current, and to extract modulation from radio signals in radio receivers—these
diodes are forms of rectifiers.
However, diodes can have more complicated behavior than this simple on–off action.
Semiconductor diodes do not begin conducting electricity until a certain threshold voltage is
present in the forward direction (a state in which the diode is said to be forward-biased). The
voltage drop across a forward-biased diode varies only a little with the current, and is a function
of temperature; this effect can be used as a temperature sensor or voltage reference.
Semiconductor diodes' nonlinear current–voltage characteristic can be tailored by varying
the semiconductor materials and introducing impurities into (doping) the materials. These are
exploited in special purpose diodes that perform many different functions. For example, diodes
are used to regulate voltage (Zener diodes), to protect circuits from high voltage surges
(avalanche diodes), to electronically tune radio and TV receivers (varactor diodes), to generate
radio frequency oscillations (tunnel diodes, Gunn diodes, IMPATT diodes), and to produce light
(light emitting diodes). Tunnel diodes exhibit negative resistance, which makes them useful in
some types of circuits.
Diodes were the first semiconductor electronic devices. The discovery of crystals'
rectifying abilities was made by German physicist Ferdinand Braun in 1874. The first
semiconductor diodes, called cat's whisker diodes, developed around 1906, were made of
mineral crystals such as galena. Today most diodes are made of silicon, but other semiconductors
such as germanium are sometimes used.
Page | 30
Figure 7.5 Diode
7.2.5 Transistor BC 548
Figure 7.6 BC 548
In electronic, transistor is a three terminals, three layer and two junction device. Collector,
base and emitter are three terminals. N, P and N are the three layer of transistor and the two
junctions are NP and PN for NPN type transistor. It may be NPN or PNP type, here we use BC
548, it is a NPN type transistor.
Page | 31
A transistor is a semiconductor device used to amplify and switch electronic signals and
power. It is composed of a semiconductor material with at least three terminals for connection to
an external circuit. A voltage or current applied to one pair of the transistor's terminals changes
the current flowing through another pair of terminals. Because the controlled (output) power
canbe much more than the controlling (input) power, a transistor can amplify a signal. Today,
some transistors are packaged individually, but many more are found embedded in integrated
circuits.
The transistor is the fundamental building block of modern electronic devices, and is
ubiquitous in modern electronic systems. Following its release in the early 1950s the transistor
revolutionized the field of electronics, and paved the way for smaller and cheaper radios,
calculators, and computers, among other things.
The essential usefulness of a transistor comes from its ability to use a small signal applied
between one pair of its terminals to control a much larger signal at another pair of terminals. This
property is called gain. A transistor can control its output in proportion to the input signal; that is,
it can act as an amplifier. Alternatively, the transistor can be used to turn current on or off in a
circuit as an electrically controlled switch, where the amount of current is determined by other
circuit elements.
There are two types of transistors, which have slight differences in how they are used in a
circuit. A bipolar transistor has terminals labeled base, collector, and emitter. A small current at
the base terminal (that is, flowing from the base to the emitter) can control or switch a much
larger current between the collector and emitter terminals. For a field-effect transistor, the
terminals are labeled gate, source, and drain, and a voltage at the gate can control a current
between source and drain.
The image to the right represents a typical bipolar transistor in a circuit. Charge will flow
between emitter and collector terminals depending on the current in the base. Since internally the
base and emitter connections behave like a semiconductor diode, a voltage drop develops
between base and emitter while the base current exists. The amount of this voltage depends on
the material the transistor is made from, and is referred to as VBE.
Page | 32
Figure 7.7 Transistor
Figure 7.8 Symbol BC-548
Page | 33
7.2.6 Photo transistor
There is a wide selection of photosensitive devices that are available to the electronic
designer. Whilst photo-diodes fulfill many requirements, phototransistors or photo transistors are
also available, and are more suitable in some applications. Providing high levels of gain and
standard devices are low cost, these phototransistors can be used in many applications.
Although ordinary transistors exhibit the photosensitive effects if they are exposed to
light, the structure of the phototransistor is specifically optimized for photo applications. The
photo transistor has much larger base and collector areas than would be used for a normal
transistor. These devices were generally made using diffusion or ion implantation.
Figure 7.9 Homo-junction planar phototransistor structures
Early photo transistors used germanium or silicon throughout the device giving a homojunction structure. The more modern phototransistors use type III-V materials such as gallium
arsenide and the like. Hetero-structures that use different materials either side of the p-n junction
are also popular because they provide high conversion efficiency. These are generally fabricated
using epitaxial growth of materials that have matching lattice structures. These photo transistors
generally use a mesa structure. Sometimes a Schottky (metal semiconductor) junction can be
used for the collector within a phototransistor, although this practice is less common these days
because other structures offer better levels of performance.
Page | 34
Figure 7.10 Hetero-junction structure phototransistor
In order to ensure the optimum conversion and hence sensitivity, the emitter contact is
often offset within the phototransistor structure. This ensures that the maximum amount of light
reaches the active region within the phototransistor.
Figure 7.11 Photo transistor
Page | 35
Phototransistor operation
Photo transistors are operated in their active region, although the base connection is left
open circuit or disconnected because it is not required. The base of the photo transistor would
only be used to bias the transistor so that additional collector current was flowing and this would
mask any current flowing as a result of the photo-action. For operation the bias conditions are
quite simple. The collector of an n-p-n transistor is made positive with respect to the emitter or
negative for a p-n-p transistor.
The light enters the base region of the phototransistor where it causes hole-electron pairs
to be generated. This mainly occurs in the reverse biased base-collector junction. The holeelectron pairs move under the influence of the electric field and provide the base current, causing
electrons to be injected into the emitter.
Phototransistor symbol
The phototransistor symbol for use in electronic circuit diagrams is very straightforward.
It is formed from the basic transistor symbol with arrows point in to it to indicate that it is light
sensitive.
The phototransistor symbol often has two arrows pointing towards it, but other
phototransistor symbols show a jagged arrow. Both versions of the phototransistor symbol are
acceptable and understood.
Page | 36
Figure 7.12Phototransistor symbol
The circuit symbol also has the convention arrow and directions on the emitter
connection. It points inwards on a PNP phototransistor circuit symbol and outwards on an NPN
phototransistor symbol.
It can be seen that the phototransistor symbol shown does not give a base connection.
Often the base is left disconnected as the light is used to enable the current flow through the
phototransistor. In some instances the base may be biased to set the required operating point. In
this case the base will be shown in the normal way on the phototransistor symbol.
Page | 37
Phototransistor circuit configurations
The phototransistor can be used in a variety of different circuit configurations. Like more
conventional transistors, the phototransistor can be used in common emitter and common
collector circuits. Common base circuits are not normally used because the base connection is
often left floating.
7.7 IC LM356
The LM386 is a power amplifier designed for use in low voltage consumer applications.
The gain is internally set to 20 to keep external part count low, but the addition of an external
resistor and capacitor between pins 1 and 8 will increase the gain to any value from 20 to 200.
The inputs are ground referenced while the output automatically biases to one-half the
supply voltage. The quiescent power drain is only 24 mill watts when operating from a 6 volt
supply, making the LM386 ideal for battery operation.
It is 8 pin IC. It is available in two packages 1st is DIP package and 2nd is SOP. This is as
shown in below figure 7.13.
Figure 7.13 Packages of LM386
We’ve use DIP package of IC LM-386. Pin out diagram IC LM-386 is as shown in figure
7.14.
Page | 38
Figure 7.14 Pin out diagram of IC LM-386
Detail of each pin of IC LM-386
Pins 1 and 8 control gain. When not connected (NC), the amplifier gain is 20. Adding a
10uF capacitor between them gives a gain of 200.
Pin 2 is the negative input – GND in our case. Pin 3 is the positive input – i.e. the actual
signal to be amplified. There is a 10K potentiometer before it, which adjusts the input signal
level, acting as a volume control.
Pins 4 (GND) and 6 (Vcc) provide the supply voltage for the amplification. For this setup
we give 5v supply from the output of the IC 7805. This gives 5v in the output pin as we mention
above in TOPIC NO. 7.2
Pin 5 is the output. It is biased to 1/2 of the supply voltage Vs. In simple terms, this
means that the signal there has two components: An AC component, which is the amplified input
signal, plus a DC component of 1/2 Vs = 2.5V.
Pin 7 is just named bypass, but the datasheet does not provide any further detail on it or
its use.
Page | 39
Absolute maximum of IC LM-386 is as shown in below figure 7.2
Sr.
Parameters
Symbol
value
1
Supply voltage
Vcc
15v
2
Power dissipation
Pd
700mW
3
Input voltage
Vin
+/- 0.4v
4
Operating temperature range
Topr
-20 to +70 .c
5
Storage temperature range
Tstg
-40 to +125 .c
No
Table 7.2 Absolute maximum of LM-386
Features of LM-386

Battery operation.

Minimum external parts.

Wide voltage range from 4-12v.

Voltage gain from 20-200.

Ground reference input

Low distortion.

8-pin dual-in-line package
Application of LM-386

AM-FM amplifier.

Portable tap amplifier.

Intercoms.

TV sound system.

Line drivers.

Ultrasonic drivers.

Small servo drivers.

Power converters.
Page | 40
7.8 Timer IC 555
The 555 is a highly stable controller capable of producing accurate timing pulses. With
monostable operation, the time delay is controlled by one external resistor and one capacitor.
With astable operation, the frequency and duty cycle are accurately controlled with two external
resistors and one capacitor.
The 555 timer is an extremely versatile integrated circuit which can be used to build lots
of different circuits.
Frequently, the 555 is used in astable mode to generate a continuous series of pulses, but
you can also use the 555 to make a one-shot or monostable circuit. The 555 can source or sink
200 mA of output current, and is capable of driving wide range of output devices.
It is also available in two type of packages 1st is DIP and 2nd is the SOP. We’ve use DIP
package in our project. Both packages of ICs are as shown in below fig 7.15
Figure 7.15 Packages of IC 555
Pin diagram IC 555 is as shown in below figure 7.16.
Page | 41
Figure 7.16 pin-out of IC 555
Features
• High Current Drive Capability (200mA)
• Adjustable Duty Cycle
• Temperature Stability of 0.005%/°C
• Timing from μSec to Hours
• Turn off Time Less than 2μSec
Application
• Precision Timing
• Pulse Generation
• Time Delay Generation
• Sequential Timing
Page | 42
Absolute maximum value for different parameters of IC 555 is as shown in table 7.3
Table 7.3 absolute maximum of IC 555
7.9 Laser diode
Figure 7.17 Laser diode
A laser diode is a laser whose active medium is a semiconductor similar to that found in a
light-emitting diode. The most common type of laser diode is formed from a p-n junction and
Page | 43
powered by injected electric current. The former devices are sometimes referred to as injection
laser diodes to distinguish them from optically pumped laser diodes.
A laser diode is formed by doping a very thin layer on the surface of a crystal wafer. The
crystal is doped to produce an n-type region and a p-type region, one above the other, resulting in
a p-n junction, or diode.
Laser diodes form a subset of the larger classification of semiconductor p-n junction
diodes. Forward electrical bias across the laser diode causes the two species of charge carrier –
holes and electrons – to be "injected" from opposite sides of the p-n junction into the depletion
region. Holes are injected from the p-doped, and electrons from the n-doped, semiconductor. (A
depletion region, devoid of any charge carriers, forms as a result of the difference in electrical
potential between n- and p-type semiconductors wherever they are in physical contact.) Due to
the use of charge injection in powering most diode lasers, this class of lasers is sometimes
termed "injection lasers “or” injection laser diode" (ILD). As diode lasers are semiconductor
devices, they may also be classified as semiconductor lasers. Either designation distinguishes
diode lasers from solid-state lasers.
When an electron and a hole are present in the same region, they may recombine with the
result being spontaneous emission — i.e., the electron may re-occupy the energy state of the
hole, emitting a photon with energy equal to the difference between the electron and hole states
involved. (In a conventional semiconductor junction diode, the energy released from the
recombination of electrons and holes is carried away as phonons, i.e., lattice vibrations, rather
than as photons.) Spontaneous emission gives the laser diode below lasing threshold similar
properties to an LED. Spontaneous emission is necessary to initiate laser oscillation, but it is one
among several sources of inefficiency once the laser is oscillating.
The difference between the photon-emitting semiconductor laser and conventional
phonon-emitting (non-light-emitting) semiconductor junction diodes lies in the use of a different
type of semiconductor, one whose physical and atomic structure confers the possibility for
photon emission. These photon-emitting semiconductors are the so-called "direct band gap"
semiconductors. The properties of silicon and germanium, which are single-element
semiconductors, have band gaps that do not align in the way needed to allow photon emission
and are not considered "direct." Other materials, the so-called compound semiconductors, have
virtually identical crystalline structures as silicon or germanium but use alternating arrangements
Page | 44
of two different atomic species in a checkerboard-like pattern to break the symmetry. The
transition between the materials in the alternating pattern creates the critical "direct band gap"
property. Gallium arsenide, indium phosphide, gallium antimonide, and gallium nitride are all
examples of compound semiconductor materials that can be used to create junction diodes that
emit light.
Uses of laser diode
Laser diodes can be arrayed to produce very high power outputs, continuous wave or
pulsed. Such arrays may be used to efficiently pump solid-state lasers for high average power
drilling, burning or for inertial confinement fusion.
Laser diodes are numerically the most common laser type, with 2004 sales of
approximately 733 million units, as compared to 131,000 of other types of lasers.
Laser diodes find wide use in telecommunication as easily modulated and easily coupled
light sources for fiber optics communication. They are used in various measuring instruments,
such as rangefinders. Another common use is in barcode readers. Visible lasers, typically red but
later also green, are common as laser pointers. Both low and high-power diodes are used
extensively in the printing industry both as light sources for scanning (input) of images and for
very high-speed and high-resolution printing plate (output) manufacturing. Infrared and red laser
diodes are common in CD players, CD-ROMs and DVD technology. Violet lasers are used in
HD DVD and Blue-ray technology. Diode lasers have also found many applications in laser
absorption spectrometry (LAS) for high-speed, low-cost assessment or monitoring of the
concentration of various species in gas phase. High-power laser diodes are used in industrial
applications such as heat treating, cladding, seam welding and for pumping other lasers, such as
diode-pumped solid-state lasers.
Uses of laser diodes can be categorized in various ways. Most applications could be
served by larger solid-state lasers or optical parametric oscillators, but the low cost of massproduced diode lasers makes them essential for mass-market applications. Diode lasers can be
used in a great many fields; since light has many different properties (power, wavelength,
spectral and beam quality, polarization, etc.) it is useful to classify applications by these basic
properties.
Many applications of diode lasers primarily make use of the "directed energy" property of
an optical beam. In this category one might include the laser printers, barcode readers, image
Page | 45
scanning, illuminators, designators, optical data recording, combustion ignition, laser surgery,
industrial sorting, industrial machining, and directed energy weaponry. Some of these
applications are well-established while others are emerging.
Laser medicine: medicine and especially dentistry have found many new uses for diode
lasers. The shrinking size of the units and their increasing user friendliness makes them very
attractive to clinicians for minor soft tissue procedures. The 800 nm – 980 nm units have a high
absorption rate for hemoglobin and thus make them ideal for soft tissue applications, where good
homeostasis is necessary.
Uses which may make use of the coherence of diode-laser-generated light include
interferometer distance measurement, holography, coherent communications, and coherent
control of chemical reactions.
Uses which may make use of "narrow spectral" properties of diode lasers include rangefinding, telecommunications, infra-red countermeasures, spectroscopic sensing, generation of
radio-frequency or terahertz waves, atomic clock state preparation, quantum key cryptography,
frequency doubling and conversion, water purification (in the UV), and photodynamic therapy
(where a particular wavelength of light would cause a substance such as porphyrin to become
chemically active as an anti-cancer agent only where the tissue is illuminated by light).
Uses where the desired quality of laser diodes is their ability to generate ultra-short pulses
of light by the technique known as "mode-locking" include clock distribution for highperformance integrated circuits, high-peak-power sources for laser-induced breakdown
spectroscopy sensing, arbitrary waveform generation for radio-frequency waves, photonic
sampling for analog-to-digital conversion, and optical code-division-multiple-access systems for
secure communication.
Page | 46
7.10 buzzer
The piezo buzzer produces sound based on reverse of the piezoelectric effect. The
generation of pressure variation or strain by the application of electric potential across a
piezoelectric material is the underlying principle. These buzzers can be used alert a user of an
event corresponding to a switching action, counter signal or sensor input. They are also used in
alarm circuits.
The buzzer produces a same noisy sound irrespective of the voltage variation applied to
it. It consists of piezo crystals between two conductors. When a potential is applied across these
crystals, they push on one conductor and pull on the other. This, push and pull action, results in a
sound wave. Most buzzers produce sound in the range of 2 to 4 kHz.
The Red lead is connected to the Input and the Black lead is connected to Ground.
Figure 7.18 buzzer
Page | 47
Piezo buzzers an electronic device commonly used to produce sound. Light weight,
simple construction and low price make it usable in various applications like car/truck reversing
indicator, computers, call bells etc. Piezo buzzer is based on the inverse principle of piezo
electricity discovered in 1880 by Jacques and Pierre Curie. It is the phenomena of generating
electricity when mechanical pressure is applied to certain materials and the vice versa is also
true. Such materials are called piezo electric materials. Piezo electric materials are either
naturally available or manmade. Piezoceramic is class of manmade material, which poses piezo
electric effect and is widely used to make disc, the heart of piezo buzzer. When subjected to an
alternating electric field they stretch or compress, in accordance with the frequency of the signal
thereby producing sound.
Encapsulated in a cylindrical plastic coating, it has a hole on the top face for sound to
propagate. A yellow metallic disc which plays an important role in the producing sound can be
seen through the hole.
Page | 48
Chapter 8
Circuit details
8.1 Circuit detail of transmitter
8.1.1 Circuit diagram of transmitter
The circuit diagram that we used in this project is given below with the values of each
component.
Figure 8.1 transmitter circuit
8.1.2 Description of the circuit
The circuit of transmitter is as shown in above figure 7.19. Heart of the circuit is the laser
diode. This is laser diode is easily available. If it is not available then we can directly use laser
pointer which is also known as laser light toy.
Working of this transmitter circuit is so easy. Output of 9v DC battery is given to the
input of the voltage regulator IC 7805. This gives 5v in output. This output voltage is used to run
next stage of the transmitter. This voltage is given to the laser pointer. So due to this the laser
diode turn on. Due to this focused light will gives in output from the laser diode.
Page | 49
8.2 Circuit detail of Receiver
8.2.1 Circuit diagram of the receiver
Figure 8.2 Receiver circuit
The circuit diagram that we used in this project is given below with the values of each
component.
8.2.2 Description of the circuit
Heart of this circuit is the photo transistor. Here other important components are IC LM386 and IC 555. Here buzzer is used to indicate the presence of person\thief into the
secure\restricted area.
When light is fall on photo transistor then it will passes the current through it. This
current is used to operate the next stages of circuit. Output of the photo transistor is given to the
pin no.3 of the IC LM386 which is non-inverting terminal of the IC LM-386.
We use IC LM-386 as the comparator. Pin no. 2 which is inverting terminal of this IC is
given to the ground. Output of IC is taken from the pin no. 5. Supply voltage Vcc is given to the
pin no.6. So output of this IC is given to the base of the transistor BC-548.
We use BC-548 as the switching element. So light is falling on to the photo transistor, all
the current will ground through the BC-548. When light is cut by some interrupt, then voltage
across the base and emitter will goes law.
So due to this reason transistor will get off. So that IC-555 get triggering pulse. So that
IC-555 will gives output according to r8Xc8 timing.
Page | 50
Chapter 9
Project design
9.1 Software design
I have made my complete project on a general purpose PCB. I prepared the layout of both
of these circuits using dip trace software. I learned dip trace software in my college. Then I
installed the software from the internet and started working on it.
Given below is the detailed description on dip trace software.
9.1.1 Dip trace
Dip Trace is EDA software for creating schematic diagrams and printed circuit boards.
The first version of Dip Trace was released in August, 2004. The latest version as of September
2011 is Dip Trace version 2.2. Interface has been translated to many languages and new
language can be added by user. There are tutorials in English, Czech, Russian and Turkish.
Starting from February 2011 Dip Trace is used as project publishing standard by Parallax.
Modules

Schematic Design Editor

PCB Layout Editor

Component Editor

Pattern Editor

Shape-Based Auto router

3D PCB Preview
Freeware and Non-Profit versions
A version of Dip Trace that is freely available with all the functionality of the full
package except it is limited to 300 pins and 2 signal layers.
Other sources

Dip Trace at Seattle Robotics Society meeting

Dip Trace at Nuts and Volts – October 2006
Page | 51

DIP TRACE Libraries by and for PICAXE microcontroller users

Review at C Net
Some hobby and educational groups such as the PICAXE forum members have developed
libraries specific to the PICAXE range of microcontroller as produced by Revolution Education
including many of the frequently used associated integrated circuits. PICAXE related libraries
can be found here:
External links

Dip Trace official Website in English

Novarm Ltd. Official Website in English
9.2 Hardware design
The hardware design of both the circuit of the project i.e. a dew transmitter circuit and a
receiver circuit include their block diagrams and list of the components used in these circuits
.
Page | 52
Chapter 10
Working of complete project
10. Working of complete project
The main purpose of our complete project is to protect our private property from the
trespasser. We can also use it at the shops, mall, bank, museum, storage room of product etc.
When the laser light transmitted through LD1 falls on phototransistor T1, the output of the opamp (IC3) at its pin 6 remains high. In this condition, the output of IC4 remains low and the
buzzer does not sound.
When the laser beam falling on phototransistor T1 is interrupted by someone, the output
of op-amp IC3 goes low and IC3 produces a pulse. This pulse triggers monostable IC4 and its
output goes high to sound the alarm for a time period of about R8xC8. The working of this
project will be clear from the flow chart described below.
figure 7.1 flowchart
Start
Laser fall on
Photo
Transistor
Yes
No action
No
Buzzer Will ring
Stop
Page | 53
Chapter 11
Advantages
11.1 advantages

Working on low input voltage.

Range can be extending.

The circuit is quite simple to do.

Lasers Having Long range, so we can cover a long area to prevent the access of Intruders
or robbers.

Low cost.

Good Efficiency.

Commonly Available Components.

Provides security.
Page | 54
CONCLUSION
Thus by using this project we can save our private property from unauthorized person.
We can provide security against unauthorized person to access our personal data, ready to use
products and our storage area etc. our circuit is special use in night or when we are not present on
our property so we can save our property from robbers. One more benefit of this project is that
there is no harm to the people and our property by its installation on our property.
Page | 55
BIBLIOGRAPHY
Circuit reference taken from
(1) www.electronicsforu.com,
(2) www.google.com,
(3) www.mycircuit9.com,
(4) www.doctronics.com
Components application and configuration are from datasheet.
Datasheet of components download from www.alldatasheet.com
Reference from the book
Page | 56