NFC Energy-Harvesting PCB Business Card with an MCU
using RF to power an MCU and 21 animated LEDs from a smartphone
In plain words
This NFC energy-harvesting business card is a PCB that powers 21 animated LEDs through radio frequency when tapped against a smartphone, requiring no battery. Designed for networking professionals and electronics enthusiasts, it stands out as a functional demonstration of PCB design and NFC energy harvesting, combining practical utility with technical innovation in an unconventional business card format.
written from the facts on this page · September 2026
From the sources
Discussed on Hacker News and featured on Adafruit , Hackaday.com , and by Microchip Technologies . Like most business cards, mine doesn’t have a battery. When it’s tapped against a phone, though, 21 LEDs start an animation, powered just by NFC. This project started about three months ago as an easy way to get more experience with PCB design. “Easy” didn’t last long. This final product taught me more about every aspect of the PCB process than I could have expected, and the result turned out way better than I imagined. The full repo is here . I’ve seen all sorts of business cards done on PCBs. Most that I’ve seen use the silkscreen and maybe exposed copper to include contact details and a QR…from wilsonharper.net
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