nRF52 NFC Batteryless

[Depraz]

Hello,

I am using Zephyr with the nRF52833 and have an NFC antenna.

In my project, I could configure NFC to work when the nRF is in system-off, following an example.
However, is it possible to use the NFC functionality when the nRF is not powered at all ? Or do I need an additional chip like the dynamic NFC tag (https://www.st.com/en/nfc/st25-dynamic-nfc-tags.html)?

From the documentation, https://infocenter.nordicsemi.com/topic/ps_nrf52833/nfc.html?cp=5_1_0_5_12 we can see that the chip is "compliant listening device NFC-A."
In the product specification https://infocenter.nordicsemi.com/topic/ps_nrf52833/keyfeatures_html5.html, it is mentioned:

• Type 2 near field communication (NFC-A) tag with wake-on field
  • Touch-to-pair support

Does this mean that the chip only support Type-2 device? I see the SDK supports the Type-4 too, so I was confused.

 

Thanks!

[Maria Gilje]

Hello,

However, is it possible to use the NFC functionality when the nRF is not powered at all ?

The NFCT peripheral needs supply power to be functional. See the electrical specification for NFCT on nRF52833.

Or do I need an additional chip like the dynamic NFC tag (https://www.st.com/en/nfc/st25-dynamic-nfc-tags.html)?

I'm not able to comment on this right now. I can ask my colleagues about it and get back to you.

Does this mean that the chip only support Type-2 device? I see the SDK supports the Type-4 too, so I was confused.

In the nrfxlib NFC library documentation it is listed that it has has support for NFC-A Type 2 and 4. NFC-A Type 4 is supported for nRF52833 as well as nRF52832, nRF52840 and nRF5340. So Type 4 is supported when it is NFC-A, but not NFC-B. The section on programming and reading an NFC tag from the NFC in NCS documentation can also be helpful.

Best regards,

Maria