This Word Clock Is as Small as They Get

Word clocks are a really neat way to display the time, because they use a clever grid of words instead of conventional numeric digits. So, for instance, it might say “the time is now twelve thirty four.” For obvious reasons, that’s more complex then simply showing some numbers. In most cases, each letter needs a light behind it to indicate which words should be read. That means that word clocks tend to be fairly large, but Hackaday.io user sjm4306’s Small Word Clock is about as tiny as they can be.

In most ways, this is a standard word clock setup. Letters are arranged in a grid, and each letter has a light behind it. But in this case, those lights are super small SMT (surface-mount technology) LEDs soldered onto a PCB. Because those LEDs are so small, sjm4306 has been able to miniaturize the entire clock. By doing that, he was able to create a fully-functional word clock that is small enough to fit in the palm of your hand.

The Small Word Clock is controlled by a PIC16F microcontroller, which uses a DS1302 serial real time clock to keep time. Using a separate real-time clock allowed sjm4306 to use the PIC16F to handle more complicated tasks, such as animations, without throwing off the time. The front face of the clock is also a PCB, with the letters created by an absence of solder mask in those areas. The LEDs are isolated by a 3D-printed window box, and the light easily shines through the face plate PCB without too much bleed over.