Using ST25R95, ST25R3911B or CR95HF with a 50 ohm antenna

[MBlac.2]

We are planning on using a NFC antenna with a 50 Ohm UFL connector. Does ST have any examples of matching their device output to 50 Ohms for this type of antenna?

Would we use a single-ended output instead of the differential output?

What would be the impact in terms of signal strength or read distance. Would the power be reduced by 50%?

[Ulysses HERNIOSUS · Accepted solution]

Hello MBlac.2,

STSW-ST25R004 and its accompanying ANs are also supporting a single-ended-cable antenna configuration. Please have a look at it.

BR, Ulysses

[msmiha]

Hi Ulysses HERNIOSUS,

I don't have any experiences with antennas, but would like to use external antenna with the CR95HF. Is the link for the software you provided also valid for this chip? Can you or someone else help me with the matching circuit for this antenna: https://www.mikroe.com/circular-nfc-r25-antenna

Best regards, Miha