XIAO nRF52840 NFC Antenna Insights

The NFC function will perform well when we use the “Seeed nRF52 mbed-enabled Boards Library”.

I managed to replicate the Arduino example code in the Wiki using the “Seeed nRF52 mbed-enabled Boards Library” as stated and both antennas below:

Both worked right just after soldering without further circuit tuning. Later, I added two 43 pF tuning caps from each NFC pad to GND to further enhance the interrogation distance for the TAOGLAS FXR.07.A.DG.

The ~40 pF cap value was calculated from subsection “6.14.10 NFCT antenna recommendations” in nRF52840 MCU product specification datasheet.

4 Likes

Hi there,
Excellent Job on this, I’m certain there isn’t any good info on the topic like this post.
Thank you for the R & D. :slight_smile:
it Should really help and demonstrate this NFC area of Xiao.
GL :slight_smile: PJ
:v: