13-06-2013, 04:29 PM
ELECTRONIC EYE FOR MODERN HOUSE
ELECTRONIC EYE.doc (Size: 3.01 MB / Downloads: 95)
INTRODUCTION
Control system for modern house is based on the Intel’s 8051 family of microcontroller using Atmel at 89C51 microcontroller since this has two ports and is most suitable for our project. Its standby current is also low compared to 89c51. The project for the modern house is implemented for security purpose and the different things are considered while implementation.
MICROCONTROLLER 89C51RD2
The device has four 8-bit I/O ports; three16-bit timer/event counters a multi-source, a four-priority-level. Nested interrupt structure. An enhanced UART on-chip oscillator and timing circuits the added features of 89C51 make it a powerful microcontroller for applications that require width modulation, high-speed I/O and up / down counting capabilities such as motor control. The embedded microcontroller used here is 89C51 microcontroller since this microcontroller has in-built peripherals it is called as embedded controller. the 89C51microcontroller is a derivative is a derivative of 8051 microcontroller whose architecture and instructions are same 8051 microcontroller with some added facilities GSM technology can provide a sophisticated theft alert system.
GSM MODULE (Optional):
GSM has been backbone of the phenomenal success in mobile telecom over the last decade. Now, at the dawn of the era of turn broadband services, GSM continues to evolve to meet new demands. GSM is an open, nonproprietary system that is evolving. One of its great strengths is the international roaming capability. This gives consumers seamless and same standardized same number contact ability in more than 212 countries. This has been a vital driver in growth with around 300 million GSM subscribers
POWER SUPPLY DESIGNING
REQUIRED REGULATED POWER SUPPLY 5V/1A OR 12V/1A: -
Almost all electronic circuits require a DC source for power supply unit may be defined as a piece of equipment, which converts the alternating waveforms from the power lines (A C supply) into an essentially direct voltage A rectifier with filter gives out unregulated supply An unregulated power – supply consists of a transformer, a rectifier, and filter circuit.There are three reasons why such a simple system is not good enough for same.
1) The first is its poor regulation i.e. the output voltage is for from constant as the load varies.
2) The second is that the D.C output voltage varies with the A.C input directly in many locations the line voltage for nominal value 230 v may vary as wide a range as 150 v to 270 v and yet it is necessary that the D.C voltage remains essentially constant.
Filter Capacitor:
Filter Capacitor design on the basis of ripple. To have a minimum ripple C should have maximum value because ripple is inversely proportional to capacitor value. The voltage rating of capacitor should be greater than Vm rating of transformer. Assumption of ripple will be from 5% to 10%.
ADVANTAGES OF PCB
When a number of identical assemblies are required, PCBs provide cost saving because once a layout is approved there is no need to check the circuit every time.
For large equipments such as computers, the saving on checking connections or wires is substantial.
PCBs have controllable and predictable electrical and mechanical properties.
1) A more uniform product is produced because wiring errors are eliminated .
2) The distributed capacitances are constant from one production to another.
3) Soldering is done in one operation instead of connecting discrete components by wires.
4) The PCB construction lands itself for automatic assembly.
5) Spiral type of inductors may be printed.
6) Weight is less.
7) All the signals are accessible for testing at any point along conductor track