Gsm Circuit Introuction Data NEW 123

7/27/2019 Gsm Circuit Introuction Data NEW 123

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1. INTRODUCTION

1.1. INTRODUCTION

Now-a-days electronics plays an important role in a day to day life. Average

people are related to electronics either as their profession or a hobby. Electronics

deals with electronic devices and their application. Electronic devices are that in

which electrons flow through a vacuum or a semiconductor and such devices have

valuable properties, which enable them to function and behave as a friend of man.

Today electronics has gained much importance due to its numerous applications in

industries. The electronic devices are capable of performing functions like,

rectification, amplification, control, generations, Conversions of electricity in line etc.

Within the last four decades we have witnessed a great revolution in the field

of electronics. Electronics has provided a new Technology to the industries, which is

widely spread than that of any other technology, in inventions. In electronics this new

technology is better known as Embedded System Design.

Think about a home appliances control by wireless protocol such as GSM

which would be controlled by mobile phone. By giving a dtmf signal, to light on /off

you to your destination. This command recognition algorithm we used could be

applied to daily life; for example it would be most helpful to disabled people to

perform their daily work. We created a secured operation using various analog circuit

designs with the Microcontrollers

1.2 NECCESSITY

The use of electricity is also very important as one of the main sources of

energy that is vital in today modern life. Presently, electrical energy is often used as

one of the main source of power to operate any electrical device or appliance. Erratic

supply of electricity leads to forgetfulness on the part of users to switch off home

appliances; this could lead to energy wastage when the light is turned on

continuously. Mechanism of information technology management could be used to

reduce wastage in electricity usage. Thus a prototype based on a microcontroller

device using GSM was developed which automatically control any electrical

equipment at home remotely both for long and short distances using mobile phone.

Hence daily electrical energy savings is made more efficient and effective.



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1.3 THEME

The GSM based switching system is totally cell phone operated device and

operated in DTMF technology. The disadvantage of this method is not completely

sealable, can be affected on large amount of dirt, dust and water. and many

advantages like high touch resolution, easy to start home appliances equipment.

1.4 OBJECTIVES

This system is divided into two modules,

GSM- Interface

Control unit

Switching Circuit

This system will detect the DTMF signal and drives the device by through

Microcontroller.



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2. LITERATURE REVIEW

2.1 HISTORY

Although the term “home automation” was first used in 1980s, the concept is

far from new. The early documented attempt to envisage something very similar dates

back to the 1960s, with Walt Disney’s Experimental Prototype Community of

Tomorrow, presented in 1966. A Smart Home will not be able to accomplish much

without appliances to control, nor will it be able to communicate to these devices in

the absence of a control network Since appliances and home network are so

interlinked with a Smart Home, the following sections provide a brief history on how

these come into being. this project is aimed at effectively using public or mobile phone from any collation of existing network to safely control electricity operated

household equipment. In addition the system to implement on this project will have

pin-check algorithm in order to enlarge salinity. Tone pair code from the decoder and

places the symbol in an internal queue for further processing. The decoder is capable

of detecting DTMF tone pairs over a wide range of amplitudes. Amongst other

applications, the project as described above can be applied in the voice/ speaker

recognition algorithm which has as its primary function the ability to recognize the

designated keypad tones and consequently turn on or off an appliance when detected.

This simple circuit can control up to three appliances without modifications. The

DTMF remote controlled system is a compact and rugged remote control unit,

designed for interface with a standard cellular mobile telephone handset. It plugs into

the “hands free” adaptor socket on the telephone handset, and operates by receiving

DTMF tones from the phone audio output. It is mains powered by electricity, and

provides three contact closures capable of switching mains voltages. By setting the

handset to auto-answer, remote control is possible at any location with cellular

coverage, and from any telephone in the world with tone-dialing capability



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3. SYSTEM DESIGN

3.1 BLOCK DIAGRAM

Fig 3.1 Block Diagram GSM Circuit

Telephone line interfaced with the circuit.

The microcontroller part interfacing the relay driver module accompanies the hardware

considered in this project. So here the relay drives the devices that are to be controlled by our

GSM protocol.

3.2 CIRCUIT DESCRIPTION

3.2.1 Working of IC MT8870

IC MT8870/KT3170 serves as DTMF decoder. This IC takes DTMF signal

coming via telephone line and converts that signal into respective BCD number. It

uses same oscillator frequency used in the remote section so same crystal oscillator

with frequency of 3.85M Hz is used in this IC.

The MT-8870 is a full DTMF Receiver that integrates both band split filter

and decoder functions into a single 18-pin DIP. Its filter section uses switched

capacitor technology for both the high and low group filters and for dial tone

rejection. Its decoder uses digital counting techniques to detect and decode all 16

DTMF tone pairs into a 4-bit code. External component count is minimized by

provision of an on-chip differential input amplifier, clock generator, and latched tri-



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state interface bus. Minimal external components required include a low-cost

3.579545 MHz crystal, a timing resistor, and a timing capacitor. The MT-8870-02 can

also inhibit the decoding of fourth column digits.

Fig.3.2 Diagram IC MT8870

The filter also incorporates notches at 350 and 440 Hz, providing excellent

dial tone rejection. Each filter output is followed by a single-order switched capacitor

section that smoothes the signals prior to limiting. Signal limiting is performed by

high gain comparators provided with hysteresis to prevent detection of unwanted low-

level signals and noise. The MT-8870 decoder uses a digital counting technique to

determine the frequencies of the limited tones and to verify that they correspond to

standard DTMF frequencies. When the detector recognizes the simultaneous

presence of two valid tones (known as signal condition), it raises the Early Steering

flag (ESt). Any subsequent loss of signal condition will cause ESt to fall. Before a

decoded tone pair is registered, the receiver checks for valid signal duration (referred

to as character recognition-condition) . This check is performed by an external RC

time constant driven by ESt. A short delay to allow the output latch to settle, the

delayed steering output flag (StD) goes high, signaling that a received tone pair has

been registered. The contents of the output latch are made available on the 4-bit

output bus by raising the three state control input to logic high. Inhibit mode isenabled by a logic high input to pin 5. It inhibits the detection of 1633 Hz.



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The output code will remain the same as the previous detected code .On

them-8870 models ,pin is tied to ground (logic low).The internal clock circuit

completed with the addition of a standard 3.579545MHz crystal .The input

arrangement of the MT-8870 provided differential input operation amplifier as well as

bias sources to bias the input at mid rail . Provision is made for a connection of a

feedback resistor op-amp output for gain adjustment

3.2.2 Signal Decoding Unit

This is the main block of the circuit which consists of microcontroller 89C51

and the relay driver IC. The controller takes the BCD input from the DTMF IC and

controls the corresponding device which has to control remotely.

3.2.3 Power Supply Unit

For the proper working of this local control section except the local telephone

set it needs a permanent back up which gives a 5V back up continuously. This is

achieved by using a 5V regulated power supply from a voltage regulated IC 7805.

This 5V source is connected to all ICs and 12 volt unregulated DC voltage is

connected to relays

3.2.4 Relay Driver Circuit

To carry out the switching of any appliances or devices we commonly use the

relays. As we are running the circuit on 5 Volt DC and 12 Volt DC, So we cannot use

this output to run the device or appliances. Therefore here we use relays which can

handle a high voltage of 230V or more, and a high current in the rate of 10Amps to

energize the electromagnetic coil of the relays +5V is sufficient. Here we use the relay

driver IC ULN 2803 to energize the relay coil.

3.2.5 Assembling Local Control Section

The whole local control section except local telephone set is assembled in a

single board, which is available in the market as common PCB. The whole circuit

except the devices is assembled in a single cabinet in which the board gets fairly fitted

along with power supply unit



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Table 3.1 Local Control Section

The connectors are provided relay switches so that the devices are connected

easily. After connecting , the device number according to table .Now power supply

are connected and device are also connected so that the Whole section is ready for

control a device using remote control telephone set.

3.3 PCB DESIGNING AND FABRICATION

In electronics system it would be vertically impossible for package without in

corpora tin printed circuit in these designs. Printed circuit in the connection mediumfor the electronics medium that assumable on opposite side of the board. Conducting

materials available are silver, brass, aluminum & copper. Copper is most wildly used.

Thickness of conducting materials depend upon current carrying capacity Of circuit

thus the thicker copper layer will have more current carrying capacity.

3.3.1 Advantage of PCB

When a number of identical assemblies are required PCB provided cost saving

because once a layout is no need to check the circuit every time.



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PCB have a controllable and predicated electrical and mechanical properties

Spiral type of inductors are printed

The distributed capacitance is constant for one production to another

Weight is less

It has miniaturization potential

When two signal lines are running close to each other is possibly of cross take

.To reduced this, an electromagnetic interference all unused copper surface are

connected to ground line is made sufficiently broad. Low power level and high

power level wire are twisted outside PCB to protect the circuit from

electromagnetic coupling.

3.3.2 Layout

Layout designing is the pencil sketch of component and conductor drawing

which contain all the relevant information for preparation of artwork . layout is

designed is the pencil sketch of component and conductors drawing which contain all

relevant information for preparation of art work. Layout is designed on tracing paper

for better accurate.

Photograph 3.1 PCB Layout



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3.3.3 Etching

Removal of unwanted copper, to give final copper pattern as ETCHING

solution which are using on Etching, is known as Enchant.

Ferric chloride

Cupric chloride

Chronic acid

Alkaline ammonia.

Out of ferric acid is wildly used because it has short etching time and it can be

stored from longer time rising follow etching.

3.3.4 Component Mounting on PCB

Careful mounting of component on PCB increases the reliability of assembly.

Component leads must be cleaned before they are inserted in PCB holes. A symmetric

load bending ti close lead bending must be avoided. The bent leads must fit into holes

properly that they can be soldered. For mounting IC, TDS,DIP package, special zip

must be used for easy insertion. All the leads must be cut with sharp cutter to same

length seen from the surface is that to be soldered.

3.3.5 Soldering

It is process in which the component and the connecting joint firmly. We get

25-Watt soldering iron and flux coated soldering wire. The solder which to be applied

till the gap of joint placed close to iron bit It is immediately melt and become bright

and fluid. Enough soldering was applied to filled up the gap of joint to give good

strength and conductivity to connection when the joint sufficient to happen filled

soldering iron removed and joint are allowed to cool down. After soldering PCB

cleaned. And made free from all the dust. All the connection is checked with the help

of Multi-meter.

The dry soldering or short connections are done. Now wiring are flexible

multi-core wire of require gauge wiring is complited.firs wire are cut down into

sufficient length. The inside core and connection are cleared and soldered connection

checked with Multi-meter.



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3.4 POWER SUPPLY DESIGN

Fig. 3.3 Power Supply Design

3.4.1 Transformer

Step down transformer is a part of regulated power supply. to step down the

mains 230V AC. we reacquire step down transformer power transformer usually

designed to operate from source of low impedance at a single frequency.

Transformer rating are expressed in volt-amp of each secondary winding ofadded total secondary VA.Temprature rise of transformer on decided on to well-

known factors i.e. losses of transformer and heat dissipating facility provided unit.

3.4.2 Rectifier Circuit

Rectifier is a circuit. Which convert AC into pulsating DC generally semi-

conducting diodes used as rectifying element due to it’s property of conducting

current in one direction only.

3.4.3 Voltage Regulator

A voltage regulator is a circuit that supplies constant voltage regardless of

change in load current.IC voltage regulator are available & cheaper.a7880series

consist of three terminal positive voltage regulator. It is a three pin IC used as

voltage regulator. It converts unregulated DC current into regulated DC current.



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3.5 Circuit diagram

Fig.3.4 Circuit Diagram GSM Based Switching System

Fig.3.6 LCD Display



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Fig. 3.7 Circuit Diagram GSN Based Switching System

3.5.1 Working of circuit

This system Dual Tone Multiple Frequency (DTMF) on our telephone set.

Every telephone set will have this facility. We have two types of dialing facility on

your telephone system Pulse dialing mode and tone dialing mode. The DTMF mode is

Shorty called as tone dialing mode.

3.5.2 What is DTMF

DTMF assigns a specific frequency (consisting of two separate tones) to each

key s that it can easily be identified by the electronic circuit. The signal generated by

the DTMF encoder is the direct algebraic submission, in real time of the amplitudes of

two sine (cosine) waves of different frequencies, i.e., pressing “5” will send a tone

made by adding 1336 Hz and 770 Hz to the other end of the mobile. DTMF stands for

the “Dual Tone Multiple Frequency”, which can generally use for the signaling. In the

touch tone system, each button on the telephone keypad is represented by a

combination of two sine-wave tones, one "low tone" and a "high tone". The low tones



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indicate what horizontal row the pressed button is in, while the high tones correspond

to the vertical column of the button.

The following table shows the common telephone keypad. The column shows

additional keys that are not usually present on telephones, but are part of the DTMF

specification. The frequencies around it indicate the tones used for each row and

column for DTMF signaling.

Table 3.2 Telephone Keypad Frequency

1209 Hz 1336 Hz 1477 Hz 1633 Hz

697 Hz 1 2 3 A

770 Hz 4 5 6 B

852 Hz 7 8 9 C

941 Hz * 0 # D

That is from above table it is seen that if the user press any key suppose, user

press the key is “3” then the tone corresponding to that key i.e. consist of two

frequencies is to be send by decoder circuit of low frequency is 697 Hz and higher

frequency is 1477 Hz is to been send.

3.6 SYSTEM HARDWARE

3.6.1 Resistor

Fig 3.8 Symbol of Resistor

Resistor is as passive component. A resistor creates resistance in a circuit .The

resistance measured in ohms is the basic unit of resistance. The resistor is used to

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chop the current. A simple resistor can be constructed using a resistive material wire

by winding it on an insulating rod.

Fig. 3.9 Construction of Resistor

3.6.2 Capacitor

Fig. 3.10 Symbol of Capacitor

A simple capacitor consists of two material plates in front of each other with a

small gap between the two plates. Metal leads are soldering to the two plates. The gap

between the plates consists of air or any other insulating material known as Di-electric

material.

Working

When DC supply is applied between the two plates P1&P2 a charge is

produced along the surface of the plates that can be stored between these plates for

some time which is known as capacitance. This capacitance is measured in unit

farads.



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Factor on which the value of capacitor depends

Distance between two plates.

Over lapping area of the plates.

Di-electric material used.

3.6.3 Diode

Fig. 3.11 Symbol of Diode

Diode is semiconductor component.

Semiconducter

Semiconductors are the substance having the electrical conductivity

intermediate to that of good conductor and insulators.

Example: Silicon, germanium etc.

N-Type Semiconducter

A semiconductor doped with a pentavalent impurity like arsenic or antimolues

has conductivity due to negatively charged electrons. Such semiconductors doped

with pentavalent impurity are called as N type semiconductors.

P-Type Semiconducter

A semiconductor doped with a trivalent impurity like indium or aluminum has

conductivity due to holes that are positive charged carriers. Such semiconductors

doped with trivalent impurity are called as P type semiconductors.

P-N Junction

If a P type semiconductor is joined to an N-type of semiconductor then the

boundary joining the two regions is called a P-N junction diode or a semiconductor

diode.



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3.6.4 Transistor

Fig. 3.12 Symbol of Transistor

A transistor is a three terminal semiconductor device. It is made by sand-

witching a thin slice of N type semiconductor between two P type semiconductors or

a thin slice of P type semiconductor between N type semiconductors.

Types of Transistor

PNP Transistor: In this transistor a thin layer of N type semiconductor is sand-

witched between two layers of P type semiconductor.

NPN Transistor: In this transistor a thin layer of P type semiconductor is sand-

witched between two N type semiconductors.

The central thin layer of transistor is called the base (B) one of the end

Fig.3.13 Types of Transistor

The central thin layer of transistor is called the base (B) one of the end layer is called an

emitter (E) and the other is called collector(C)



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3.6.5 IC LM7805

The LM78XX series of three terminal regulators is available with several

fixed output voltages making them useful in a wide range of applications. One of

these is local on card regulation, eliminating the distribution problems associated with

single point regulation. The voltages available allow these regulators to be used in

logic systems, instrumentation, Hi-Fi, and other solid state electronic equipments.

Although designed primarily as fixed voltage regulators, these devices can be used

with external components to obtain adjustable voltages and currents.

The LM78XX series is available in an aluminum TO-3 package which will

allow over 1.0A load current if adequate heat sinking is provided. Current limiting is

included to limit the peak output current to a safe value. Safe area protection for the

output transistor is provided to limit internal power dissipation

Fig.3.14 Diagram of Physical Shape and Pin

If internal power dissipation becomes too high for the heat sinking provided,

the thermal shutdown circuit takes over preventing the IC from overheating.

Considerable effort was expanded to make the LM78XX series of regulators easy touse and minimize the number of external components. It is not necessary to bypass

the output, although this does improve transient response. Input bypassing is needed

only if the regulator is located far from the filter capacitor of the power supply. For

output voltage other than 5V, 12V and 15V the LM117 Series provides an output

voltage range from 1.2V to 57V.

3.6.6 Microcontroller 89c51



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Fig. 3.15 Pin Diagram of IC AT89C51

Description

The device is manufactured using Atmel high density nonvolatile memory

technology and is compatible with the industry standard 80C51 and 80C51 instruction

set and pin out. The on-chip Flash allows the program memory to be reprogrammed

in-system or by a conventional nonvolatile memory programmer. By combining a

versatile 8-bit CPU with Flash on a monolithic chip, the Atmel AT89C51 is a

powerful microcomputer which provides a highly flexible and cost effective solution

to many embedded control.

Feature

Compatible with MCS-51™ Products

8K Bytes of In-System Reprogrammable Flash Memory

Fully Static Operation: 0 Hz to 24 MHz

128 x 8-Bit Internal RAM

32 Programmable I/O Lines



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RST:

Reset input. A high on this pin for two machine cycles while the oscillator is

running resets the device. This pin drives High for 96 oscillator periods after the

Watchdog times out. The DISRTO bit in SFR AUXR (address 8EH) can be used to

disable this feature. In the default state of bit DISRTO, the RESET HIGH out feature

is enabled.

ALE/PROG :

Address Latch Enable (ALE) is an output pulse for latching the low byte of the

address during accesses to external memory. This pin is also the program pulse input

during Flash programming. In normal operation, ALE is emitted at a constant rate of

1/6 the oscillator frequency and may be used for external timing or clocking purposes.

Note, however, that one

ALE pulse is skipped during each access to external data memory. If desired,

ALE operation can be disabled by setting bit 0 of SFR location 8EH. With the bit set,

ALE is active only during a MOVX or MOVC instruction. Otherwise, the pin is

weakly pulled high. Setting the ALE-disable bit has no effect if the microcontroller is

in external execution mode.

PSEN :

Program Store Enable (PSEN) is the read strobe to external program memory.

When the AT89C51 is executing code from external program memory, PSEN is

activated twice each machine cycle, except that two PSEN activations are skipped

during each access to external data memory.

EA/VPP :

External Access Enable, EA must be strapped to GND in order to enable the

device to fetch code from external program memory locations starting at 0000H up to

FFFFH.

XTAL1:

Input to the inverting oscillator amplifier and input to the internal clockoperating circuit.



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XTAL2 :

Output is from the inverting oscillator amplifier.

Fig.3.16 Oscillator Amplifier

3.6.7 Oscillator Characteristics

XTAL1 and XTAL2 are the input and output, respectively, of an inverting

amplifier that can be configured for use as an on-chip oscillator, as shown in Figure

11. Either a quartz crystal or ceramic resonator may be used. To drive the device from

an external c lock source, XTAL2 should be left unconnected while XTAL1 is driven,

as shown in Figure 12. There are no requirements on the duty cycle of the external

clock signal, since the input to the internal clocking circuitry is through a divide-by-

two flip-flop, but minimum and maximum voltage high and low time specifications

must be observed.

Memory Organization:

MCS-51 devices have a separate address space for Program and Data

Memory. Up to 64K bytes each of external Program and Data Memory can be

addressed.



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Program Memory:

If the EA pin is connected to GND, all program fetches are directed to external

memory. On the AT89C51, if EA is connected to VCC, program fetches to addresses

0000H through 1FFFH are directed to internal memory and fetches to addresses

2000H through FFFFH are to external memory.

Data Memory:

The AT89C51 implements 128 bytes of on-chip RAM. The upper 128 bytes

occupy a parallel address space to the Special Function Registers. This means that the

upper 128 bytes have the same addresses as the SFR space but are physically separate

from SFR space. When an instruction accesses an internal location above address

7FH, the address mode used in the instruction specifies whether the CPU accesses the

upper 128 bytes of RAM or the SFR space. Instructions which use direct addressing

access of the SFR space.

3.6.8 Relay

General-Purpose Electromagnetic Relay This is low cost electromagnetic

relay, which is adaptable to many applications and is not special in any way. It is

electromagnetic relay.

The parts of the relay are of an core and surrounding coil of wire, an iron yoke

which provides a low reluctance path for magnetic flux, the yoke being shaped so that

the magnetic circuit can be closed by a movable piece iron called the set of contacts.

The armature is hinged to the yoke and held by a spring in such a way that there is an

air gap in the magnetic circuit. When an electric current flows through the coil, the

armature is attracted to the iron core. Electrical switching contacts are mounted on the

armature. When the relay coil is energized, these movable contacts break their

connection with one set of fixed contacts (normally closed) and close a connection to

previously open contacts (normally open). When electric power is removed from the

coil, a spring returns the armature to its original position.

POWER RELAY:

When the control signal is extremely small, it is sometimes necessary to use asensitive relay to control the current through the coil of a larger relay. In such a case



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the first relay is called a pilot relay and is sensitive enough to operate with the small

signal. Because it is so sensitive, its contacts have to be quite small and they carry

only enough current to operate the coil of the large relay

Fig. 3.17 Circuit Diagram of Relay

3.6.9 LCD Lampex 16 x 2 LCD Display

Liquid Crystal Display which is commonly known as LCD is an

Alphanumeric Display it means that it can display Alphabets, Numbers as well as

special symbols thus LCD is a user friendly Display device which can be used for

displaying various messages unlike seven segment display which can display only

numbers and some of the alphabets. The only disadvantage of LCD over seven

segment is that seven segment is robust display and be visualized from a longer

distance as compared to LCD. Here I have used 16 x 2 Alphanumeric Display which

means on this display I can display two lines with maximum of 16 characters in one

line



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Definition of Terminals:

Table 3.3 Terminals Name

Pin No. Symbol Function

1. Vss Ground terminal of module

2. Vdd Supply terminal of module, +5v

3. Vo Power supply for liquid crystal drive

4. RS

Resister select

RS=Ø…..instruction register

RS=1…….data register

5. R/W

Read/Write

R/W=1…Read

R/W= Ø…Write

6. E(E1) Enable

7-14 DB Ø-DB7

Bidirectional data bus.

Data transfer is performed once,thru

DB Ø-DB7, in the case of interface data

Length is 8-bits; & twice thru DB4-DB7

In the case of interface data length is 4

bits. Upper 4 bits first then lower 4 bits.

15. LAMP-(L-) LED or EL LAMP power supply terminals.

16. LAMP+(L+) LED or EL LAMP power supply terminals

17. E(2) Enable

Operating Specification:

Table 3.4 Operating Temperature

Standard Temperature Wide Temperature

Operating temp range -10˚ to +55˚c -20˚ to +70˚c

Storage temp range -20˚ to +70˚c -30˚ to +80˚c

90% MAX 90% MAX 90% MAX



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Electrical Characteristic

Table 3.4 Electrical Characteristics

Supply voltage 4.5 to 5.5v

Supply current (16x2) 3 ma

3.6.10 Power Supply Requirment

Fig. 3.18 Power Supply

This circuit shows the typical power supply connection for all dot matrix

modules. The display voltage is slightly different for different version. Recommended

end user to use a variable resistor as shown in circuit for optimum VLCD adjustment

to obtain best display contrast and viewing angle. Back light facility can be use by providing supply greater than 12V.

3.7 TESTING AND TROUBLE SHOOTING

Testing is nothing but the physically checking of all component and all

possible condition to avoid problem in the circuit fluctuating.

Testing is done with so many checking instrument as per the circuit

requirement and condition.



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Bare board testing:

Continuity of track

Over etching or under etching.

Shorts it any

Vcc and GND track

Trouble Shooting:

After the PCB prepared the conductivity test is carried out. first pin-to-pin

conductivity checked. The necessary IC interconnection also checked. The resistive

value of all the resistor are checked and completed with the value denoted color

coding is done.

The capacitor also checked to see whether they are working or short or open.

The diodes are test for priority. The diodes are checked for forward resistance and

reversed resistance. After carrying out possible testing, jumper wire also test.



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4. CONCLUSIONS

4.1 CONCLUSION

In this way we have studied in this project i.e. “APPLIANCE CONTROLUSING GSM SYSTER” such as relay, transformer, capacitor, diode, fuse, Board and

constructional parts. Also study the mounting of component, soldering & testing of

component.

In this project we have to study of all type of precaution. we have taken the

making of any instrument or project.

4.2 FUTURE SCOPE

This system provides feedback on cell phone of farmers in the farm of text

msg with the help of microcontroller. As the know person or animal is trying to break

the electric fence then the control circuit séances that and provides electric shock to

that person or animal and also sends the msg to the former that any one intruder is

trying to enter in the field also this system provides sign us (Text msg ) for dry

running of motor and canal feeding to the mobile phone of former.

SCADA System :

In future when the SCADA system is well developed and everyone is familiar

with it then we would like to introduce our project with “SCADA”. Which gives

graphical representation of our whole field on personal computer of former.

4.3 APPLICATION:

The circuit is applicable at industries for control the machinery.

The circuit is applicable for driving robot from any place.

The principle is applicable for operation of the human from any place by

doctor.

The principle is useful for multichannel information belt.

The circuit is applicable at mine for working without remote.

The principle is applicable for robotic tank, robotic swipe, and robotic

submarine at the time of war. The principle is also useful for supply the water to farm, garden, etc .



4.4 ADVANTAGES

High touch resolution

Highest image clarity

All glass panel, no coatings or layers that can wear out or damage.

4.5 FETURES

You can control up to 10 devices. It may be any electric or electronic

appliances or devices with simple to heavy appliances. Each device is given a

unique code.

It makes accurate switching, any false switching of device are not done.

There is no risk for false switching.

Your local phone can be used for normal use by using a DPDT switch.

To perform any operations through remote phone line, the user needs to dial to

the local telephone then the respective code of the device is dialed.

This system detects the ringing signal from your exchange with the help of

ring detector and automatically switches ON.

This device saves your money. This circuit switches OFF after a time of 60

seconds.

Before changing the state of the device we can confirm the present status of

the device.

4.5 LIMITATION

The receiver must reside in a location where a signal with sufficient strength

can be received from a cellular phone network.

Only devices with electrical controlling input ports will be possible targets for

control.

Operation of the controlling unit is only possible through a cell phone with

control capabilities.

The Controlling unit must be able to receive and decode the data.

Documents

Gsm Circuit Introuction Data NEW 123