PWM FED MOSFET CONTROLLED STREET LIGHT AUTO INTENSITY
CONTROL IN 8 STEPS
SUBMITTED BY
EDGEFX TEAM
ABSTRACT
• High Intensity Discharge lamps (HID) used for
urban street light are based on principle of gas
discharge
• White Light Emitting Diode (LED) can replace
the HID lamps where intensity control is possible
by pulse width modulation
BLOCK DIAGRAM
HARD WARE EQUIPMENTS
• POWER SUPPLY BLOCK
• MICROCONTROLLER (AT89S52/AT89C51)
• LED
• PWM
• MOSFET
• BC547
• 1N4007
• RESISTORS & CAPACITORS
EMBEDDED SYSTEMS
Definition for :- EMBEDDED SYSTEMS
A combination of hardware and software which together
form a component of a larger machine.
An example of an embedded system is a microprocessor that
controls an automobile engine.
An embedded system is designed to run on its own without
human intervention, and may be required to respond to
events in real time.
EMBEDDED SYSTEMS
MICRO CONTROLLER
Compatible with MCS®-51 Products
8K Bytes of In-System Programmable (ISP) Flash
Memory
4.0V to 5.5V Operating Range
Crystal Frequency 11.0592MHZ
Three-level Program Memory Lock
256 x 8-bit Internal RAM
32 Programmable I/O Lines
Three 16-bit Timer/Counters
Eight Interrupt Sources
Full Duplex UART Serial Channel
Watchdog Timer
AT89S52
PIN DIAGRAM OF AT89S52
PWM
• The PWM switching frequency has to be much faster than
what would affect the load, which is to say the device that uses
the power.
• The term duty cycle describes the proportion of on time to the
regular interval or period of time;
• a low duty cycle corresponds to low power, because the power
is off for most of the time. Duty cycle is expressed in percent,
100% being fully on.
PWM APPLICATIONS
•Telecommunications
•Power delivery
•Voltage regulation
•Audio effects and amplification.
MOSFET
Metal–Oxide–Semiconductor field-effect
transistor (MOSFET, MOS-FET, or MOS
FET)
MOSFET is a device used for amplifying or
switching electronic Signals
MOSFET as a switch & P- Type , N-Type MOSFET
BC547The BC547 transistor is an NPN Epitaxial
Silicon Transistor.
The BC547 transistor is a general-purpose
transistor in small plastic packages.
It is used in general-purpose switching and
amplification BC847/BC547 series 45 V, 100 mA
NPN general-purpose transistors.
Whenever base is high, then current starts
flowing through base and emitter and after that
only current will pass from collector to emitter
BIBILOGRAPHY
The 8051 Microcontroller and Embedded systems” by Muhammad Ali
Mazidi and Janice Gillispie Mazidi , Pearson Education.
ATMEL 89S52 Data Sheets.
www.atmel.com
www.beyondlogic.org
www.wikipedia.org
www.howstuffworks.com
www.alldatasheets.com
THANK ‘Q’