Who would think about using electronic device instead of real birthday cake. But who knows – there might be few nerds who would like such thing. Maksym thought it would be cool to create such device. It not only mimics birthday cake but also have piezo sensor which reacts to air flow. So it can be blow on to make it flicker and go out.
Circuit is built around Attiny44 microcontroller with 9 LEDs attached to it. Cake is made of two PCBs where one is dedicated to control circuit while another carries LEDs with sensor in the middle. There are many things that can be improved here. First of all it needs random LED flickering for better candle mimic. There probably would be great to have varying number of LEDs to match the birthday age. Probably different Charliepelxing algorithm could do the trick. Some nice 3D printed case wouldn’t hurt also.