Atmel at89c51 Office-Home Security System Circuit Diagram
Home aegis project
Securiy is a amount of abundant affair to all of us in this world. Normally there are four types of aegis blackmail to our property.
1 )Thief, an inturder.
2)Fire, so we use blaze sensor.
3)Water spilage /over flow, so we use baptize sensor.
4) Gas aperture , we use gas sensor, whenever there is aegis aperture from one of aloft or any aggregate of above.
The activity takes the afterward action
1) Sounds an ALARM to allure your home Aegis project
or accessible absorption .
2) If the displace sw is not apprenticed aural 30 abnormal the projects takes added action,
3) It makes an emergency alarm to bear an emergency bulletin stored in accent IC.
4) It will accomplish bristles attempts to alarm you afore it checks the altitude again.
Atmel at89c51 Office-Home Aegis System PCB
The activity presented actuality is based on world’ s best able intel’ s mcs-51 ancestors of microcontroller atmel at89c51. CIRCUIT EXPLANATION: This activity is based on 8051 microcontroller.(IC2) IC3 and is acclimated as buffer. IC4 is a one time programmable(otp) dent area letters are stored. This is 21 additional accent ic area absolute of 12 letters can be recorded on eight altered locations, but absolute continuance should not be added than 21 seconds. Recorded letters can be played aback by ambience the activate pin 10 & 11 to high, authoritative these pin low will stop the message, Ambience these pin aerial will again epitomize the aforementioned message. IC5 is an audio amplifire . Audio achievement from accent ic(IC4) pin no 7 cout is accompanying to this ic on pin no 3 through VR2 aggregate ascendancy and C10. Amplified achievement from pin no 5 drives the apostle through capacitor C14. R14 and C13 corrects the tone. .C15 and C16 couples the audio bulletin to blast line. IC4 needs 3.3v operating voltage .R9 is a voltage bottomward resistor, D7 is 3.3v zener diode and C7 is a clarify capacitor. These apparatus will consistently advance the voltage to3.3v at pin 9,12 of IC4. capacitor C8 is a augment aback capacitor.,C9 and R13 affiliated to pin no 7 of IC 4 are accent corrector.R12 forth with the VR1 capricious resistor performs the sampling amount adjustment. R10 and R11 affiliated to pin26 and pin 27 of the microcontroller are voltage bottomward resistors. R15 and R16 affiliated to the abject of transister Q1 and Q2 are voltage bottomward resistors and drives transistors Q1 & Q2 back set to aerial argumentation by microcontroller. Q1 Drives the punch broadcast RL1and Q2 drives the off-hook relay.