The main objective of this project is to design a maintenance free and low-cost light which automatically turns on and off at the predetermined time of the day.
This kind of light helps to reduce power waste and save energy. In these days people have a habit to turn on at least one light of there residence if they are going out of home for a couple of days. Then lights start to blazing all day and night and waste lots of energy. If we can use this programmable light, then we can configure it to turn on every night and turn off at the next day by without any human involvement.
The core component of this programmable light is ATmega8 low power CMOS microcontroller. The main reason to select this microcontroller is it’s lower cost and higher availability. Except for the above two reasons this microcontroller also bundled with a rich set of peripherals which including 23 GPIOs, 3 independent timers, Two-wire serial interface, EEPROM, etc.
Apart from ATmega8 microcontroller, this system uses DS1307 real time clock to maintain system time. Like ATmega8, DS1307 is also a very popular RTC in the market.
This controller is designed to work with a 24V DC power supply. The main reason to select 24V is that most of the medium power LED modules in the market are designed to work with that voltage. During my search all the medium power LED modules which I found are designed to work with 20V – 28V range. Out of those LED modules, the majority of modules are rated for 24V input.
For this circuit, the recommended power supply is 24V 1.5 A portable switch mode power supply. Except for the LED driver stage the all other parts of this light controller is designed to work with 5V. MC34063 DC-to-DC converter is used to supply 5V to those components.
Read more: PROGRAMMABLE LIGHT CONTROLLER WITH ATMEGA8 AND DS1307
