intoduction remote elec switch board

7/28/2019 Intoduction Remote Elec Switch Board

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RF REMOTE ELECTRIC

SWITCH BOARD

Presented By:

Nallawala Zaineb.

Kaydawala Alefiya.

Reference:Sanjay Vaishnav

C.B.Pagi

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CERTIFICATE

The is to certify that miss zaineb

Nallawala studing in semester 7TH semester has

Completed her project report on the topicRF REMOTE

ELECTRIC SWITCH BOARD successfully.

Staff in charge Head of the

Department

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Date :

ACKNOWLEDGEMENT

A man had make a progress in a

communication so i think to prepare a seminar on such a

topic. This topic is based on advanced technology. Its very

true that behind every success of any student there is

always a teacher. Firstly I would like to thanks H.O.D profSanjay Vaishnav.

I also very thanks to my staff members who

have helped me. I would like to thanks my friend

Who keep my spirits high listen to me patiently and

always give their support. I am also thankful to my parents

for their inspiration and encouragement without which my

struggle would become more difficult.

Nallawala Zaineb

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INDEX

1. INTRODUCTION

2. BLOCK DIAGRAM

3. BLOCK DIAGRAM DESCRIPTION

4. CIRCUIT DIAGRAM

5. CIRCUIT DESCRIPTION6. HARDWARE DESIGN

7. HARDWARE DESCRIPTION

8. LIST OF COMPONENT

9. TESTING AND RESULTS

10.FURTURE EXPANSION

11.ADVANTAGES,DISADVANTAGES &

APPLICATION

12.BIBILOGRAPHY

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INTRODUCTION

Project name is RF Remote Electric Switch Board which can

control an electronics appliances as well as electric appliances through a

remote. RF remote can be operated in100m range. In this circuit we are

operating 4-channel device. By using microcontroller 89s52 can display RF

range on a LCD as well as any operating electric appliances. Here we are

using RF transmission and RF receiver to controlling electric appliances.

In todays world, there is a continuous need for controlling

appliances with the increase in standard of living; there is a sense of urgency

for developing circuits that would ease the complexity of life. Therefore we

had thought to design a RF 4-channel operating device which is controlling

four appliances through a remote by a user requirement.

When user is pressing any switch from remote data would be

encoded an RF transmitter will transmit a data to the RF receiver, it receive

data an pass a decoded data to the microcontroller AT89s52 through it

display on a LCD.

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BLOCK DIAGRAM AND ITS

DESCRIPTION

Block Diagram of RF Transmitter

RF SIGNAL

6

RF TX SENSOR

RF ENCODER

IC

HT640

CONTROL

KEYPADE


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Block Diagram of RF Receiver

SIGNAL FROM RF REMOTR

7

POWER

SUPPLY

MICROCONTROLL

ER

89S52

RF REC

SENSOR

DRIVER

CKT

R1

R2

R3

R4

RF DECODE

ICHT648


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R1 TO R4 IS DIFFERENT RELAY THROUGH THAT U CAN

OPERATE

Block Diagram Description

Block Diagram of RF Transmitter is shown in fig1 consist of

following essential blocks.

RF TX Sensor.

RF Encoder HT-640

Control Keypad

RF TX Sensor:- Here we use STT-433 is ideal for remote

control applications where low cost and longer range is

required. The transmitter operates from a 1.5-12V supply,

making it ideal for battery-powered appliances. Range of

transmitter is 100 meters. RF TX sensor will transmit the

encoded data.

RF Encoder HT-640:-The 3 encoders are a series of CMOS LSI

forremote control system applications. They are capable of

encoding 18 bits of information which consists of N address

bits and 18_N data bits. Each address/data input is externally

trinary programmable if bonded output.

Control Keypad:-Here we had used a four switch to send a data to

encoder. This control switch is controlling a electrical appliances as per user

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requirement. The data would be in a analog signal converted into digital

through a decoder and send it to RF sensor.

Block Diagram of RF Receiver is shown in fig2 consist of

following essential blocks.

Power Supply

Microcontroller At89s52

RF Receiver Sensor

RF decoder HT-648

Driver Circuit

Power Supply:-Here we used +12V and +5V dc power supply. The main

function of this block is to provide the required amount of voltage to

essential circuits. +12 voltage is given. +12V is given to relay driver. To get

the +5V dc power supply we have used here IC 7805, which provides the

+5V dc regulated power supply.

Microcontroller AT89s52:-It is a low-power, high performance CMOS

8-bit microcontroller with 8KB of Flash Programmable and Erasable Read

Only Memory (PEROM). The device is manufactured using Atmels high-

density nonvolatile memory technology and is compatible with the MCS-

51TM 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 hip, the Atmel AT89S52 is a powerful. Microcontroller,which

provides a highly flexible and cost effective solution so many embedded

control applications.

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RF Receiver Sensor:- The STR-433 is ideal for short-range remote

control application where cost is primary concern. The receiver module

require no external RF components except for the antenna. It generate

virtually no emission making FCC and ETSI approval easy. The super-

regenrative design exhibits exceptional sensitivity at very low cost.

RF Decoder HT-648:-The 318 decoder are series of CMOS LSI for

remote control system applications. They are paired with the 318 series of

encoders. For proper operation a pair of encoder/decoder pair with the samenumber of address and data format should be selected. The 318 series of

decoder receiver serial address and data from that series of encoder that are

transmitted by a carrier using an RF.

Driver Circuit:-This block has the potential to drive the various controlled

devices. In this block mainly we are using the transistor and the relays. One

relay driver circuit we are using to control the light. Output signal from

AT89S52 is given to the base of the transistor, which we are further

energizing the particular relay. Because of this appropriate device is selected

and it do its allotted function.

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CIRUIT DIAGRAM AND ITS

DESCRIPTION

Transmitter circuit

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Receiver circuit

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(Continue)

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Circuit Description

RF electric switch board is nothing but a switching system. RF electric

switch board consist of transmitter and receiver circuit.

Transmitter Circuit:-

when we connect the circuit with 12v battery the LED glow in a

circuit as it shows a circuit is working. A 7805 transistor is used to convert

5V power supply .100uf is connected with 7805 to filter output voltage.

Now here HT640 encoder is used to transmit an RF data. We had

connected 4- electric switch to an encoder at data pin. When we press any

switch the encoder will take as an serial input. Dout pin of encoder is

connected with 3-pin header. Encoder is sending a data to 3-pin header

through a Dout pin. 3-pin header is nothing but an RF transmitter which

consist of VCC, ground and Dout pin. Now RF transmitter will transmit a

data to RF receiver at the same address.

Receiver Circuit:-

When we connect A.C. power supply to a transformer which

transform an A.C. current to a circuit. Now rectifier used to convert A.C. to

dc power supply. Through a step-down transformer we get 12v power

supply. Here a 7805 transistor is used to convert 5V power supply. 100uf is

connected with 7805 to filter output voltage.5V power supply is needed for a

AT89s52 microcontroller. LED will glow if an RF transmitter and RF

receiver will be in a RF range.

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Now RF receiver will receive a data transmitted from an RF

transmitter. 3-pin header of RF receiver will receive a data at Din pin. Now

Din pin will work as an serial input pin for an Ht648l decoder. Now decoder

will decode a data from a same address as it encoded. A decoder will pass a

data to a microcontroller AT89s52 at port p1. Now microcontroller will

recognize that switch is press once or a twice. IF a switch is press once then

it would display on LCD as ON or if it is press twice it would display on

LCD as OFF. Microcontroller will find which pin of port p1 is high after

word port p3 is used for output pin which transfer a data to ULN2003 to

drive a relay ON to glow a LED and microcontroller will display on LCD at

the same time. ULN2003 is a driver circuit which drives a relay to operate a

4-relay through it. Through a relay we can operate a fan, tubelight, bulb and

other electric appliances which are connected to it. Variable resistor is

connected to LCD to change a brightness of LCD.

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HARDWARE DESIGN AND ITS

DESCRIPTION

Transmitter Circuit

Receiver Circuit

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Hardware Description

Procedure Followed While Designing:

In the beginning I designed the circuit in DIPTRACE software.

Dip trace is a circuit designing software. After completion of the designing

circuit I prepared the layout.

Then I programmed the microcontroller using KEIL software

using hex file.

Then soldering process was done. After completion of the

soldering process I tested the circuit.

Still the desired output was not obtained and so troubleshooting

was done. In the process of troubleshooting I found the circuit aptly soldered

and connected and hence came to conclusion that there was error in

programming section which was later rectified and the desired results were

obtained.

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LIST OF COMPONENTS

Following is the list of components that are necessary to

build the assembly of the Digital Speedometer Cum Odometer:

Microcontroller AT89S52

Power supply

Wheastern bridge

IC 7805 LED

RF SENSOR

RF Decoder

RF Encoder

Transformer 12-0-12, 500 mA

Preset 10K

Disc capacitor 1000uF,100uF,33pF,1mF

Reset button switch

3-PIN HEADER

UNL2003

Relay

Transistor

LCD(16X2)

Resistor

Crystal Oscillator

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Description of Components

1. Microcontroller AT89S52: The AT89S52 is a low-power, high-performance CMOS 8-bit

microcontroller with 8K bytes of in-system programmable Flash memory.

The device is manufactured using Atmels high-density nonvolatile memory

technology and is compatible with the Industry-standard 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 pro-

grammar. By combining a versatile 8-bit CPU with in-system programmable

Flash on a monolithic chip, the Atmel AT89S52 is a powerful

microcontroller which provides a highly-flexible and cost-effective solution

to many embedded control applications.

The AT89S52 provides the following standard features: 8K bytes of

Flash, 256 bytes of RAM, 32 I/O lines, Watchdog timer, two data pointers,

three 16-bit timer/counters, a six-vector two-level interrupt architecture, a

full duplex serial port, on-chip oscillator, and clock circuitry. In addition, the

AT89S52 is designed with static logic for operation down to zero frequency

and supports two software selectable power saving modes. The Idle Mode

stops the CPU while allowing the RAM, timer/counters, serial port, and

interrupt system to continue functioning. The Power-down mode saves theRAM contents but freezes the oscillator, disabling all other chip functions

until the next interrupt or hardware reset.

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Pin Description

VCCSupply voltage.

GNDGround.

Port 0Port 0 is an 8-bit open drain bidirectional I/O port. As an output port, each

pin can sink eight TTL inputs. When 1s are written to port 0 pins, the pins

can be used as high impedance

inputs.

Port 0 can also be configured to be the multiplexed low order address/data

bus during accesses to external program and data memory. In this mode, P0

has internal pull ups.

Port 0 also receives the code bytes during Flash programming and outputs

the code bytes during program verification.External pullups are required

during program

verification.

Port 1Port 1 is an 8-bit bidirectional I/O port with internal pullups.

The Port 1 output buffers can sink/source four TTL inputs. When 1s are

written to Port 1 pins, they are pulled high by the internal pullups and can be

used as inputs. As inputs,

Port 1 pins that are externally being pulled low will source current (IIL)

because of the internal pull ups. In addition, P1.0 and P1.1 can be configured

to be the timer/counter 2 external count input (P1.0/T2) and the

timer/counter 2 trigger input (P1.1/T2EX), respectively, as shown in the

following table.Port 1 also receives the low-order address bytes during Flash programming

and verification.

Port 2Port 2 is an 8-bit bidirectional I/O port with internal pull ups.

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The Port 2 output buffers can sink/source four TTL inputs. When 1s are

written to Port 2 pins, they are pulled high by the internal pull ups and can

be used as inputs. As inputs, Port 2 pins that are externally being pulled low

will source current (IIL) because of the internal pull ups.

Port 2 emits the high-order address byte during fetches from external

program memory and during accesses to external data memory that use 16-

bit addresses (MOVX @ DPTR). In this application, Port 2 uses strong

internal pull ups when emitting 1s. During accesses to external data memory

that use 8-bit addresses (MOVX @ RI), Port 2 emits the contents of the P2

Special Function Register.

Port 2 also receives the high-order address bits and some control signals

during Flash programming and verification.

Port 3

Port 3 is an 8-bit bidirectional I/O port with internal pull ups.The Port 3 output buffers can sink/source four TTL inputs. When 1s are

written to Port 3 pins, they are pulled high by the internal pull ups and can

be used as inputs. As inputs,

Port 3 pins that are externally being pulled low will source current (IIL)

because of the pull ups.

Port 3 also serves the functions of various special features of the AT89S52,

as shown in the following table.

Port 3 also receives some control signals for Flash programming

and verification.

RSTReset 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/PROGAddress 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 (PROG)

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

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timing or clocking purposes. Note, however, that one ALE pulse is skipped

during each access to external data memory.

FEATURES:-

8 KB Reprogrammable flash.

32 Programmable I/O lines.

16 bit Timer/Counter3.

8 Interrupt sources.

Power range: 4V 5.5V

Endurance: 1000 Writes / Erase cycles

Fully static operation: 0 Hz to 33 MHz

Three level program memory lock

Power off flag

Full duplex UART serial channel

Low power idle and power down modes

Interrupt recovery from power down modes

256 KB internal RAM

Dual data pointer

2. Power Supply:

Here we used +12V and +5V dc power supply. The main function

of this block is to provide the required amount of voltage to essential

circuits. +12 voltage is given. +12V is given to relay driver. To get the +5V

dc power supply we have used here IC 7805, which provides the +5V dc

regulated power supply.

3. Wheatstone Bridge:

The circuit we now know as the Wheatstone Bridge was actually

first described by Samuel Hunter Christie (1784-1865) in 1833. However,

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Sir Charles Wheatstone invented many uses for this circuit once he found

the description in 1843. As a result, this circuit is known generally as the

Wheatstone Bridge.

One very common application in industry today is to monitor

sensor devices such as strain gauges. A second application is used by

electrical power distributors to accurately locate breaks in a power line. The

method is fast and accurate, and does not require a large number of field

technicians. Other applications abound in electronic circuits.

4. LM7805(Voltage Regulator):

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Fig. 4.7 Voltage Regulator

The KA78XX/KA78XXA series of three-terminal positive

regulator are available in the TO-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.

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

5. LED:

A light-emitting diode (LED) is a semiconductorlight source.

LEDs are used as indicator lamps in many devices, and are increasingly used

forlighting. Introduced as a practical electronic component in 1962, early

LEDs emitted low-intensity red light, but modern versions are available

across the visible, ultraviolet and infrared wavelengths, with very high

brightness.

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Characteristics of LEDs9

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Forward Voltage (VF) drop across LED

Diodes are current driven!

Wavelength variations

Crystal and junction growth defects

Brightness variations

Crystal defects resulting formationof phonons and non-radiationenergytransfer

Temperature

Junction temperature of the deviceaffects each of the parametersabove

Applications:Old days

Signal Indicators

Numeric and Alpha-numeric displays

NowadaysAutomotive

Backlights

Flashlights for portable devices

General illumination

Projector Light Sources

Signage

Torch Lights

Traffic Lights

6. RF SENSOR:

433MHzRF Transmitter (STT433): The STT-433 is ideal for

remote control applications where low cost and longer range is required. The

transmitter operates from a 1.5-12V supply, making it ideal for battery-

powered applications. The transmitter employs a SAW-stabilized oscillator,

ensuring accurate frequency control for best range performance. Output

power and harmonic emissions are easy to control, making FCC and ETSI

compliance easy. The manufacturing-friendly SIP style package and low-

cost make the STT-433 suitable for high volume applications. The oscillator

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start-up time is on the order of 40uSec, which limits the maximum data rate

to 4.8 kbit/sec.

Specification:

Features:

433.92 MHz Frequency

Low Cost

1.5-12V operation

11mA current consumption at 3V

Small size

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Pin Description

Pin Name DescriptionANT 50 ohm antenna output. The antenna port impedance affects

output power and harmonic emissions. An L-C low-pass filter may

be needed to sufficiently filter harmonic emissions. Antennacan be single core wire of approximately 17cm length or PCB traceantenna.

VCC Operating voltage for the transmitter. VCC should be bypassedwith a .01uF ceramic capacitor and filtered with a 4.7uF tantalumcapacitor. Noise on the power supply will degrade transmitternoise performance.

DATA Digital data input. This input is CMOS compatible and should bedriven with CMOS level inputs.

GND Transmitter ground. Connect to ground plane.

Application:

Remote Keyless Entry (RKE)

Remote Lighting Controls

On-Site Paging

Asset Tracking

Wireless Alarm and Security Systems

Long Range RFID

Automated Resource Management

433MHZ RF Receiver (STR433): The STR-433 is ideal for short-

range remote control applications where cost is a primary concern. The

receiver module requires no external RF components except for the antenna.

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It generates virtually no emissions, making FCC and ETSI approvals easy.

The super-regenerative design exhibits exceptional sensitivity at a very low

cost. The manufacturing-friendly SIP style package and low-cost make the

STR-433 suitable for high volume applications.Data is sent as a constant

rate square-wave. The duty cycle of that square wave will generally be either

33% (a zero) or 66% (a one).The data slicer on the STR-433 is optimized for

use with PWM encoded data, though it will work with NRZ data if certain

encoding rules are followed.

Specification

Pin Outs:Pin Name Description

ANT Antenna input.

GND Receiver Ground. Connect to ground plane.

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VCC(5V) VCC pins are electrically connected and provide operatingvoltage for the receiver. VCC can be applied to either or both.VCC should be bypassed with a .1F ceramic capacitor.Noise on the power supply will degrade receiver sensitivity.

DATA Digital data output. This output is capable of driving one TTLor CMOS load.It is a CMOS compatible output.

Features:

Low Cost

5V operation

3.5mA current drain

No External Parts are required

Receiver Frequency: 433.92 MHZ

Typical sensitivity: -105dBm

IF Frequency: 1MHz

Application:

Car security system

Sensor reporting

Automation system

Remote Keyless Entry (RKE)

Remote Lighting Controls

On-Site Paging

Asset Tracking

Wireless Alarm and Security Systems

Long Range RFID

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Automated Resource Management

RF ENCODER:

The 318encoders are a series of CMOS LSIs for remote control

system applications. They are capable of encoding 18 bits of information

which consists of N address bits and 18_N data bits. Each address/data input

is externally trinary programmable if bonded out. It is otherwise set floating

internally. Various packages of the 318encoders offer flexible combinations

of programmable address/data to meet various application needs. The

programmable address/data is transmitted together with the header bits viaan RF or an infrared transmission medium upon receipt of a trigger signal.

The capability to select a TE trigger type or a DATA trigger type further

enhances the application flexibility of the 318series of encoders.

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Features:

Operating voltage: 2.4V~12V

Low power and high noise immunity CMOS technology

Low standby current

Three words transmission

Built-in oscillator needs only 5% resistor

Easy interface with an RF or infrared transmission media

Minimal external component

Applications:

Burglar alarm system

Smoke and fire alarm system

Garage door controllers

Car door controllers

Car alarm system

Security system

Cordless telephones

Other remote control systems

RF DECODER:

The 318 decoders are a series of CMOS LSI for remote control

system applications. They are paired with the 318 series of encoders. For

proper operation a pair of encoder/decoder pair with the same number of

address and data format should be selected (refer to the encoder/decoder

cross reference tables).

The 318 series of decoders receives serial address and data from

that series of encoders that are transmitted by a carrier using an RF or an IR

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transmission medium. It then compares the serial input data twice

continuously with its local address. If no errors or unmatched codes

are encountered, the input data codes are decoded and then transferred to the

output pins. The VT pin also goes high to indicate a valid transmission.

The 318 decoders are capable of decoding 18 bits of information

that consists of N bits of address and 18N bits of data. To meet various

applications they are arranged to provide a number of data pins whose range

is from 0 to 8 and an address pin whose range is from 8 to 18. In addition,

the 318 decoders provide various combinations of address/data number in

different packages.

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Features:

Operating voltage: 2.4V~12V

Low power and high noise immunity CMOS technology

Low standby current

Capable of decoding 18 bits of information

Pairs with HOLTEKs 318 series of encoders

8~18 address pins

0~8 data pins

Trinary address setting

Two times of receiving check

Built-in oscillator needs only a 5% resistor

Valid transmission indictor

Easily interface with an RF or an infrared transmission medium

Minimal external components

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Applications:

Burglar alarm system

Smoke and fire alarm system

Garage door controllers

Car door controllers

Car alarm system

Security system

Cordless telephones

Other remote control systems

RELAY CIRCUIT:

Fig. 4.8 Relay

A single pole dabble throw (SPDT) relay is connected to port RB1

of the microcontroller through a driver transistor. The relay requires 12 volts

at a current of around 100ma, which cannot provide by the microcontroller.

So the driver transistor is added. The relay is used to operate the external

solenoid forming part of a locking device or for operating any other

electrical devices. Normally the relay remains off. As soon as pin of the

microcontroller goes high, the relay operates. When the relay operates and

releases. Diode D2 is the standard diode on a mechanical relay to prevent

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back EMF from damaging Q3 when the relay releases. LED L2 indicates

relay on.

ULN2003:

The ULN2001A, ULN2002A, ULN2003 and ULN2004Aare high

voltage, high current darling ton arrays each containing seven open collector

darling ton pairs with common emitters. Each channel rated at 500mAand

can withstand peak currents of 600mA.Suppressiondiodesare included for

inductive load driving and the inputs are pinned opposite the outputs to

simplify board layout.

These versatile devices are useful for driving a wide range of loads

including solenoids, relays DC motors, LED displays filament lamps,

thermal print heads and high power buffers.

The ULN2001A/2002A/2003Aand 2004Aare supplied in 16 pin

plastic DIP packages with a copper lead frame to reduce thermal resistance.

They are available also in small outline package (SO-16) as

ULN2001D/2002D/2003D/2004D.

The four versions interface to all common logic families:

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ULN2001A General Purpose, DTL, TTL, PMOS,

CMOS

ULN2002A 14-25V PMOS

ULN2003A 5V TTL, CMOS

ULN2004A 615V CMOS, PMOS

SEVENDARLINGTONS PER PACKAGE

OUTPUT CURRENT 500mA PER DRIVER

(600mA PEAK)

OUTPUT VOLTAGE 50V

INTEGRATED SUPPRESSION DIODES FOR

INDUCTIVE LOADS

OUTPUTS CAN BE PARALLELED FOR HIGHER CURRENT

TTL/CMOS/PMOS/DTLCOMPATIBLE INPUTS

INPUTS PINNED OPPOSITE OUTPUTS TO SIMPLIFY LAYOUT

Transformer:-

Device that transfers electric energy from

one alternating-current circuit to one or more other circuits,

either increasing (stepping up) or reducing (stepping down)

the voltage. Uses for transformers include reducing the line

voltage to operate low-voltage devices (doorbells or toy

electric trains) and raising the voltage from electric

generators so that electric power can be transmitted over

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long distances. Transformers act through electromagnetic

induction; current in the primary coil induces current in the

secondary coil. The secondary voltage is calculated by

multiplying the primary voltage by the ratio of the number

of turns in the secondary coil to that in the primary.

LCD(16x2):

Short forliquid-crystal display.A low-power, flat-panel display used in many digital devices to

display numbers or images. It is made of a liquid containing crystals that are affected by electric

current, sandwiched between filtering layers of glass or plastic. LCDs do not produce light of their

own; instead, when electric current is passed through the material, the molecules of the "liquid

crystal" twist so that they either reflect or transmit light from an external source.

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FEATURES:

5 x 8 dots includes cursor

Built - in controller (KS 0066 or Equivalent)

+ 5V power supply

1/16 duty cycle

LED can be driven by pin 1, pin 2 or A and K

N.V. optional for + 3V power supply

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Resistor:

Aresistoris a two-terminalelectronic componentthat producesavoltageacross its terminals that isproportionalto theelectriccurrentthrough it in accordance withOhm's law:

V=IRResistors are elements ofelectrical networksand electronic circuits and areubiquitous in most electronic equipment. Practical resistors can be made of

various compounds and films, as well asresistance wire(wire made of ahigh-resistivity alloy, such as nickel-chrome).

The primary characteristics of a resistor are theresistance, thetolerance,the maximum working voltage and thepowerrating. Other characteristicsincludetemperature coefficient,noise, andinductance. Less well-knowniscritical resistance, the value below which power dissipation limits the

maximum permitted current, and above which the limit is applied voltage.Critical resistance is determined by the design, materials and dimensions of

the resistor.

Resistors can be integrated intohybridandprinted circuits, as wellasintegrated circuits. Size, and position of leads (or terminals), arerelevant to equipment designers; resistors must be physically large enough

not to overheat when dissipating their power.

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http://en.wikipedia.org/wiki/Terminal_(electronics)http://en.wikipedia.org/wiki/Electronic_componenthttp://en.wikipedia.org/wiki/Voltagehttp://en.wikipedia.org/wiki/Proportionality_(mathematics)#Direct_proportionhttp://en.wikipedia.org/wiki/Electric_currenthttp://en.wikipedia.org/wiki/Electric_currenthttp://en.wikipedia.org/wiki/Ohm's_lawhttp://en.wikipedia.org/wiki/Electrical_networkshttp://en.wikipedia.org/wiki/Resistance_wirehttp://en.wikipedia.org/wiki/Electrical_resistancehttp://en.wikipedia.org/wiki/Engineering_tolerance#Electrical_component_tolerancehttp://en.wikipedia.org/wiki/Power_(physics)http://en.wikipedia.org/wiki/Temperature_coefficienthttp://en.wikipedia.org/wiki/Electrical_noisehttp://en.wikipedia.org/wiki/Inductancehttp://en.wikipedia.org/w/index.php?title=Critical_resistance&action=edit&redlink=1http://en.wikipedia.org/wiki/Hybrid_circuithttp://en.wikipedia.org/wiki/Printed_circuit_boardhttp://en.wikipedia.org/wiki/Integrated_circuitshttp://en.wikipedia.org/wiki/Terminal_(electronics)http://en.wikipedia.org/wiki/Electronic_componenthttp://en.wikipedia.org/wiki/Voltagehttp://en.wikipedia.org/wiki/Proportionality_(mathematics)#Direct_proportionhttp://en.wikipedia.org/wiki/Electric_currenthttp://en.wikipedia.org/wiki/Electric_currenthttp://en.wikipedia.org/wiki/Ohm's_lawhttp://en.wikipedia.org/wiki/Electrical_networkshttp://en.wikipedia.org/wiki/Resistance_wirehttp://en.wikipedia.org/wiki/Electrical_resistancehttp://en.wikipedia.org/wiki/Engineering_tolerance#Electrical_component_tolerancehttp://en.wikipedia.org/wiki/Power_(physics)http://en.wikipedia.org/wiki/Temperature_coefficienthttp://en.wikipedia.org/wiki/Electrical_noisehttp://en.wikipedia.org/wiki/Inductancehttp://en.wikipedia.org/w/index.php?title=Critical_resistance&action=edit&redlink=1http://en.wikipedia.org/wiki/Hybrid_circuithttp://en.wikipedia.org/wiki/Printed_circuit_boardhttp://en.wikipedia.org/wiki/Integrated_circuits


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Specification:

Features:

Selected superior quality material

Automated mass scale production

Superior electrical performance

Heat and wet proof epoxy coating

Colour band marking for easy identification

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TESTING AND RESULT

We started our project by making power supply. That is easy for

me but when we turn toward the main circuit, there are many problems and

issues related to it, which we faced, like component selection, which

components is better than other and its feature and cost wise a We started

our project by making power supply. That is easy for me but when I turn

toward the main circuit, there are many problems and issues related to it,

which are I faced, like component selection, which components is better than

other and its feature and cost wise also, then refer the data books and other

materials related to its.

I had issues with better or correct result, which I desired and also

the software problem.

I also had some soldering issues which were resolved using

continuity checks performed on the hardware.We had issues with better or correct result, which we desired and

also the software problem.

We also had some soldering issues which were resolved using

continuity checks performed on the hardware.

We started testing the circuit from the power supply. There we got

over first trouble. After getting 9V from the transformer it was not converted

to 5V and the circuit received 9V.

As the solder was shorted IC 7805 got burnt. So we replaced the

IC7805.also the circuit part around the IC7805 were completely damaged

with the help of the solder we made the necessary paths.

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FUTURE EXPANSION

By using this circuit and proper power supply we can implement various

appliances as bulb, tube lights, fan etc.

By modifying this circuit we can operate 8-channel device.

If we fixed one address code so we can use as RFID.

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ADVANTAGES, DISADVANTAGES &

APPLICATION

Advantages:Low cost.

Effort less

Work as a Remote

Disadvantages:

It cannot be used outward of RF range.

Application:A Device can be operate from any where in a RF range.

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BIBILOGRAPHY

Reference Books:

Programming in ANSI C: E BALAGURUSAMY

The 8051microcontroller and embedded systems: MUHAMMAD ALI

MAZIDI

JANICE GILLISPIE MAZIDI

The 8051 microcontroller: KENNETH J. AYALA

Website:

www.8051projects.info

www.datasheets4u.com

www.8051.com
http://www.8051projects.info/http://www.datasheets4u.com/http://www.8051.com/http://www.8051projects.info/http://www.datasheets4u.com/http://www.8051.com/

intoduction remote elec switch board

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