NFC Energy-Harvesting PCB Business Cards Run Without a Battery

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A new category of PCB business cards uses NFC energy harvesting to power an onboard microcontroller without any battery, drawing electricity from a smartphone's 13.56 MHz magnetic field. The card's etched trace antenna acts as an inductor, converting RF energy into regulated DC power sufficient to run low-power MCUs like the WCH CH552 or ATTiny85. Dedicated energy-harvesting chips such as the STMicroelectronics ST25DV series enable stable power delivery, supporting LEDs or even small e-paper displays. Designers can build these cards using open-source schematics on GitHub and order them from prototyping services like JLCPCB. The technology is aimed at developers, cybersecurity professionals, and tech founders seeking a functional, high-tech alternative to conventional business cards.

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