Developing a LED Sunrise Alarm Clock

Figure 1 

This small LED sunrise alarm clock is mad to provide sufficient bright light similar to the light of sunrise to avoid suffering from a mood disorder known as Seasonal Affective Disorder (SAD).

A fully open source ATmega168 is the basis of building this project as the device emits the bright sunrise light every time the alarm clock is ringing. The clock chosen contains a 9V backup battery in case the power goes out. The disassembly of the clock is easy wherein 4 screws are located on the bottom and 3 screws keep the button PCB board fastened to the top of the clock case. The 9V clip needs to be threaded through the hole in the bottom half to take the top off and get better access to the LCD. Inside the clock are the transformer, piezoelectric speaker for the alarm, some diodes for rectifier circuit, some buttons for the inputs, and a clock display.

For the power supply, a simple regulator circuit was used with just 2 capacitors and a 5V regulator. A current regulator is required to power the LEDs since the ATmega168 can only deliver 16mA of current each.

Rest of the project