NFC tag powers richer user interfaces

February 28, 2014 // By Julien Happich
At Embedded World, NXP was demonstrating a new kind NFC tag, the NTAG I2C, offering not only a passive NFC Forum compliant contactless interface but also an I²C contact interface together with energy harvesting circuitry.


The latter enables the chip to communicate with a microcontroller and power small electronics (like LEDs) as it harvests energy from a reader such as an NFC-enabled smartphone.

What’s more, an additional externally powered 64-byte SRAM memory buffer mapped into the memory allows a fast data transfer between the RF and I²C interfaces and vice versa, without the write cycle limitations of the EEPROM memory.

Practically, this means that the NTAG I2C can exchange data over the air (from the NFC tag’s memory to the reader), but also over its I²C interface with the electronic appliance it is embedded in. 

This could be for zero power configuration, where a reader could be used to configure any consumer electronics or home appliances even after manufacture, to perform late customization, such as setting up the language or various options.