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Senior
April 24, 2020
Solved

Use single ended antenna no AAT with ST25R3916

  • April 24, 2020
  • 3 replies
  • 889 views
  1. What should I take care of when using a single ended 50 Ohm antenna without AAT?
  2. What changes I need to do with the analog configures comparing to the example one given in X-CUBE-NFC6? Are there some references for this usage case?

Thanks.

    This topic has been closed for replies.
    Best answer by Travis Palmer

    ​Hello Diverger,

    1.) For HW you will need a matching network from target matching impedance to 50 Ohm, a 50Ohm cable (optional) and a 50Ohm Antenna.

    There are some threads in the comunity mentioning 50Ohm matching network configurations. We are releasing soon (next week) a new version of the ST25R Antenn matching tool which does this calculation for you.

    2.) you have to propperly configur the Single and RFO bit of the "IO Configuration register".

    BR Travis

    3 replies

    Travis Palmer
    Travis PalmerBest answer
    ST Employee
    April 24, 2020

    ​Hello Diverger,

    1.) For HW you will need a matching network from target matching impedance to 50 Ohm, a 50Ohm cable (optional) and a 50Ohm Antenna.

    There are some threads in the comunity mentioning 50Ohm matching network configurations. We are releasing soon (next week) a new version of the ST25R Antenn matching tool which does this calculation for you.

    2.) you have to propperly configur the Single and RFO bit of the "IO Configuration register".

    BR Travis

    Ulysses HERNIOSUS
    ST Technical Moderator
    April 24, 2020

    Hi,

    hint on the mentioned threads: You will find them by searching "single ended st25r3911b" and "50ohm st25r3911b". Different chip but same principles (and bits) apply.

    Regards, Ulysses

    divergerAuthor
    Senior
    April 24, 2020

    Yes, I think I've done right for it. I designed the matching network in ADS. And I'm very appreciated for your work to simplify the​ designing procedure.