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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 con- tents 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_circuits7/28/2019 Intoduction Remote Elec Switch Board
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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/