The Concept

I sometimes have trouble waking up in the morning, so I wanted to make a challenge for myself whenever I try to turn off my alarm clock. I already made a memory game, and I made a simple design for outputting to a 7-segment LED display, so I decided I wanted to integrate those designs into an alarm clock.

The Design

The box

I found an inexpensive aluminum project box online and decided to use it as the body for the alarm clock. I found some buttons with built-in LEDs for the memory game portion, and I decided to strategically drill holes in the front of the box to  allow the time display to shine through. Like I mention in the demo video, I didn’t do a great job of this.

The Circuit Board

The main electrical components I have on the PCB are:

• ATMega328 – system logic and I/O
• DS1307 – Real Time Clock
• 3V coin cell for real time clock
• LED Display
• MAX7219 for LCD screen
• Buzzer for alarm
• Resistors, capacitors, and crystal oscillators

In order to fit everything into the small project box, I went with a stacking PCB design with two 2-layer boards.

The buttons and lights are connected by wires to the circuit board where they are directly soldered on. In future, I would like to modify this to a plug-in connection to make it easier to take the lid off for battery replacement.

Features

• Requires a memory game to be beaten to turn off alarm
• All functions of alarm clock are controlled by 4 memory game buttons
• Buttons light up whenever pressed for feedback
• Intuitive alarm and time setting
• Adjustable brightness
• Adjustable difficulty
• 12/24 hour time display modes

Demo

Making Of

The code and PCB schematics can be found on my GitHub.