Wilson Harper designed a business card that harvests energy through NFC, showcasing his skills in electronics. The PCB, which is the size of a typical business card, contains 21 Charlieplexed LEDs and a small microcontroller. Thanks to the PCB antenna designed using STM’s antenna inductance tools and an LLM script added to KiCad, the card powers its LEDs when placed on the back of phones with NFC readers, which are common in 2026. The design files were shared on GitHub.
Why it matters
The project shows that NFC technology can be used not only for data exchange but also as an energy source for producing a visible output in small electronic circuits. In this respect, the work offers a concrete example of designing an antenna, microcontroller and numerous LEDs together within the limited space of a business card. Sharing the design files on GitHub allows the approach used to be examined by electronics enthusiasts and those developing similar circuits. However, the information provided about the card’s operating distance with different NFC-reader-equipped phones, LED brightness and the continuity of power transfer remains limited; the project’s practical scope depends on these details.