LAPTOP THEFT IDENTIFIER. GUIDED BY, Mrs . S.NITHYA .,(M.E)AP/ECE.

PRESENTED BY, SHEFALI MOHAN , (612911106089). N.SUDHA, (612911106101). S.HARINI, (612911106303). R.VANITHA, (612911106114).

ABSTRACT Objective: The objective of this project is to identify the theft identification in a particular product for example laptop.

Block Diagram

INTRODUCTION Accelerometer:

An accelerometer is a device that measures proper acceleration An accelerometer is a device that measures proper acceleration. Most accelerometers do not display the value, but supply it to other devices. An accelerometer measures proper acceleration, which is the acceleration it experiences relative to free fall and is the acceleration felt by people and objects. Put another way, at any point in space time the equivalence principle guarantees the existence of a local inertial frame, and an accelerometer measures the acceleration relative to that frame. Such accelerations are popularly measured in terms of g-force.

Comparator: In electronics, a comparator is a device which compares two voltages or currents and switches its output to indicate which is larger. An operational amplifier (op-amp) has a well balanced difference input and a very high gain. The parallels in the characteristics allows the op-amps to serve as comparators in some functions.

ALARM: An alarm gives an audible or visual warning about a problem or condition. Alarms include: alarm clocks can produce an alarm at a given time. burglar alarms, designed to warn of burglaries; this is often a silent alarm: the police or guards are warned without indication to the burglar, which increases the chances of catching people.

safety alarms, which go off if a dangerous condition occurs safety alarms, which go off if a dangerous condition occurs. Common public safety alarms include: tornado sirens. fire alarms . "Multiple-alarm fire", a locally-specific measure of the severity of a fire and the fire-department reaction required. car alarms . community Alarm or autodialer alarm (medical alarms). personal alarm.

ALARM CIRCUIT:

Circuit description: The circuit is designed to control the buzzer. The buzzer ON and OFF is controlled by the pair of switching transistors (BC 547). The buzzer is connected in the Q2 transistor collector terminal. When high pulse signal is given to base of the Q1 transistors, the transistor is conducting and close the collector and emitter terminal so zero signals is given to base of the Q2 transistor. Hence Q2 transistor and buzzer is turned OFF state.

When low pulse is given to base of transistor Q1 transistor, the transistor is turned OFF. Now 12v is given to base of Q2 transistor so the transistor is conducting and buzzer is energized and produces the sound signal.

block diagram description microcontroller :

MICROCONTROLLER: A microcontroller is a complete microprocessor system built on a single IC. Microcontrollers were developed to meet a need for microprocessors to be put into low cost products. The microcontroller contains full implementation of a standard MICROPROCESSOR, ROM, RAM, I/0, CLOCK, TIMERS, and also SERIAL PORTS.

Microcontroller also called "system on a chip" or "single chip microprocessor system" or "computer on a chip”. Today microcontrollers are very commonly used in wide variety of intelligent products. For example most personal computers keyboards and implemented with a microcontroller.

Pin Diagram 89c51

Pin Description VCC: Supply voltage. GND: Ground. Port 0: Port 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 1: Port 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.

Port 2: Port 2 is an 8-bit bidirectional I/O port with internal pullups. 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 pullups and can be used as inputs.

Port 3: Port 3 is an 8-bit bidirectional I/O port with internal pullups. The Port 3 output buffers can sink/source four TTL inputs.

RESET: Reset input. A high on this pin for two machine cycles while the oscillator is running resets the device. ALE/PROG: Address Latch Enable 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.

POWER SUPPLY Block diagram: PSEN: Program Store Enable is the read strobe to external program memory.   POWER SUPPLY Block diagram: TTransformer TRANSFORMER rRECTIFIER fFilter FILTER IC REGULATOR LOAD

IC voltage regulators: Voltage regulators comprise a class of widely used ICs. Regulator IC units contain the circuitry for reference source, comparator amplifier, control device, and overload protection all in a single IC.

Circuit diagram (Power supply):

ADVANTAGES:

APPLICATIONS: