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nmeunier
Associate
December 12, 2022
Solved

How does eDesignSuite calculate NFC matching components ?

Hello,

I have to tune several NFC antennas using a ST25R3911b and I would like to automate calculations of the matching circuit depending on the antenna parameters (Rs,L,Rp,SRF). Using the eDesignSuite is a bit heavy since I have several antennas and it implies to fill manually all the fields. So I would like to perform my own calculations of matching circuit.

I used the method described in the attached file to calculate NFC matching components and my result for Cs and Cp are slightly different from the eDesignSuite results.

So I would like to know how the calculations are made by the eDesignSuite.

Cordially,

Nicolas Meunier.

This topic has been closed for replies.
Arimsa Has
Arimsa HasBest answer
ST Employee
December 12, 2022

Hi @nmeunier​,

in app note "ST25R single ended antenna matching - Application note" and "Antenna matching for ST25R3911B/ST25R391x devices - Application note", you can found the formulas , which are used for the calculation in the eDesignsuite.

Please also consider das some fine tuning my be needed, depending on the accuracy of the measurement of "Matching + Antenna".

Best regards.

2 replies

Arimsa Has
Arimsa HasBest answer
ST Employee
December 12, 2022

Hi @nmeunier​,

in app note "ST25R single ended antenna matching - Application note" and "Antenna matching for ST25R3911B/ST25R391x devices - Application note", you can found the formulas , which are used for the calculation in the eDesignsuite.

Please also consider das some fine tuning my be needed, depending on the accuracy of the measurement of "Matching + Antenna".

Best regards.

nmeunier
nmeunierAuthor
Associate
December 13, 2022

Perfect, thank you !