If you’ve been following some of my most recent posts (and I hope you have!) you will have seen several different clock designs. While they are quire different, they share several things in common – namely being built on an Arduino platform, incorporating a DS3231 Real Time Clock (with battery backup) and driving some number of addressable LEDs.
While I have built prototypes using the UNO, Nano and Pro Mini Arduino boards, I needed a more cost-effective solution. I designed a PCB to take an Atmega328 and its associated components, the RTC module and a 6-pin header for a removable FTDI USB interface module (only required to download software). While this is a very simple design I added headers for all analog and digital pins. I created the schematic and PCB routing using the free Fritzing software. The software is pretty intuitive and comes with a large library of pre-defined components, although I did find it challenging to create and edit new components. Nevertheless, I’ll use it again and recommend it to others.
I read a message on a local bulletin board that mentioned Dirty Boards, a Hong-Kong based low-cost, no-frills PCB manufacturer. I uploaded the boards’ design files (more on that later) and 3 weeks later (and $24 lighter) I received 12 (not the 10 promised) boards. Excellent!