This certainly isn’t the first DIY smartwatch we’ve featured, but it really stands out thanks to its easy-to-read e-ink display and the fact that the wristband is part of the actual PCB. That’s possible thanks to PCB fabrication services that have recently started to offer flexible PCBs at a reasonable prices. The Schmartwatch is controlled by a Nordic Semiconductors nRF52832 MCU, which is built on an Arm Cortex-M4 and has onboard BLE (Bluetooth Low Energy) communications.
The e-ink display that Basti chose is a GDEW0154Z17, which is 1.5″, has three colors, and a resolution of 150×150 pixels. That’s all powered by a 3V CR2032 coin cell battery. The PCB is, of course, the most interesting part of the project. Basti designed that in KiCAD, and the PCB itself is intended to be the wristband. Basti says that the flexible PCB will need to be stiffened with plastic at certain points to protect it, but it’s still a very novel design and we’re looking forward to seeing more as the project progresses.