2025-06-17 1:11 AM - edited 2025-06-17 3:21 PM
Hello
I’m currently designing an NFC product using the ST25R3911B reader IC and evaluating two standard NFC antennas from Leankon for read distance performance:
LK1860701 (larger size)
LK1860601 (smaller size)
Matching Circuit Optimization:
Used datasheet parameters to optimize the matching network for both antennas.
Followed the recommended test methodology from the datasheet.
Test Tag:
Evaluated performance using ST’s Tag 5 as the reference target.
Results:
Both antennas achieved a similar read distance of ~80mm.
However, according to Leankon’s datasheet, the LK1860701 should achieve ~100mm.
Is this discrepancy normal? Could there be variations due to environmental factors or matching circuit tuning?
Are there any key considerations I might have missed to further improve the read distance?
For reference, two antenna datasheets are attached,
LK1860101 NFC antenna
LK1860701 NFC Antenna
I’d appreciate any insights or suggestions. Thank you!
2025-06-24 12:05 AM
Hello Stephen2,
Did you do your own reader board or do you use the ST25R3911B-DISCO as used in the datasheet of the tag.
There are two possible limitations for a NFC reader system:
1.) Tag communication is limited by the power transfer
--> optimize antenna size and output power to increase coupling and power transfer
2.) Tag communication is sensitivity limited
--> the backscatter is too small to be understood by the reader, there might be noise sources on the PCB/in the system which disturbs the receiver
In addition the following post provide further details additional details:
There are also two other posts linked, which might be of interest.
I propose that you try to reproduce the same setup as stated in the DS of the antenna. Maybe contacting the antenna manufacturer is a good idea to get further information how the ST25R3911B has been tuned.
please let us know, if you have additional questions.
BR Travis
2025-06-27 5:47 AM
Hello Travis
Thank you so much for your kind reply.
I contacted Leankon and they provided their recommended matching values, then I can get the similar distance compared to their DS.
Thank you again.