A Seven-Segment Clock with PCB Face

This unique clock uses printed circuit board as face, sets the time via NTP.

Jeremy Cook
5 months ago

It seems that making your own clock is something of a hacking rite of passage. While this addressable LED clock isn't my first attempt at making a DIY timepiece, I'm quite happy with how it turned out so far.

This clock features 85 addressable SK6812 LEDs, which form four seven-segment digits, with two LEDs per segment. Additionally, a colon accounts for another pair of LEDs and the final 27 LEDs form a small matrix display below the numbers. Control is handled by an ESP32 WiFi chip mounted to a Wemos S2 mini board, which logs on to my home network to the time automatically via NTP.

What's perhaps the most unique feature of this clock is the dual printed circuit board arrangement. All electronics are mounted on a traditional base board, while a top PCB forms the visible clock face via gaps in the solder mask. A 3D-printed light separator between the two PCBs keeps photons (mostly) in their designated zones.

As of now, the clock boots up, gets the time, and displays it in a 24-hour format. It's programmed to change colors based on whether its morning, noon-ish, or afternoon/night, and also uses the ESP32's touch sensitivity to change colors on-demand. A pseudo-random pattern of colors creates a blinkenlights effect on the bottom panel.

It's a neat display, but there is so much more I could do with this design. The capacitive inputs present an exciting number of possibilities, as do the broken out I/O and LED signaling. In the next iteration I'll use copper, not just solder mask, to more effectively block non light-up sections. This project may just be getting started, but it's at least in a usable state!

Jeremy Cook
Engineer, maker of random contraptions, love learning about tech. Write for various publications, including Hackster!
Latest articles
Sponsored articles
Related articles
Latest articles
Read more
Related articles