Introduction: Remote Contrlolled Home Application With Memory Function
by utilize this circuit we can control 4 relay using ir remote and by utilize the eeprom function it will remember the last state of relays even during power loss
Step 1: Gather All Necessery Component
Lets not waste time and gather all necessery component for this project,
the required components are following,
1) ATMEGA8-U (Or any similar microcontroller will work) x1
2) uln2003 (or uln2803)x1
3) 16mhz crystal x1
4) 22p ceramic capasitor x2
5) 104p ceramic capasitor x1
6) 12v spdt relay x4
7) 10k smt resistor x10 (0805 package)
8) 1N4148 smt diode x4
9) 1000mfd 16v capasitor x1
10) 220mft 10v capasitor x1
11) 7805 linear voltage regulator with hwat sink x1
12) tsop1938 ir receiver (or any similar will work just fine) x1
13) male/female header (optonal)
14) db107 bridge rectifier
15) screw terminal x6
16)10k resistor x1
17)220 to 12v step down transformar (500MA or greater) x1
18) IR remote (usb kit remote) x1
Step 2: IT IS SOLDERING TIME
you can order a prototype pcb using the provided garber file below, or you can built into a perf board using given schemetic, if you want to built it in prototype board then use the image referance , althouth you also can referance with schemetic,
Note: due to design error a capasitor polarity is wrong in the footprint , please check it before soldering or it will explode for sure, This circuit utilize the on chip eeprom to remember the last state of relay during power failure so we canno use the arduino reset pin to reset the relays, so connect a reset switch between the arduino digital pin 4 and vcc 5v, it will reset all relay off, similar action can be perform by using the ir remote power button,
Note: the footprit i used for relay driver is uln2803 but i m using uln2003 , so you have to make solder jumper between pin8 and pin9, and pin17 and pin18, or you can just use uln2803,
Step 3: PROGRAMMING TIME
i think you already have bootloader burned , if not you can find tutorial in youtube, You can use a usb to uart converter to program the chip, or just swap this ic with a working arduino ,select proper chip type (in this case atmega 8), you can use atmega168 or 328 .
and upload the given code,, and done,
it is uses a common usb kit remote found in electronics store,
but you can modify the given code in order to use another remote,
