Hello, my name is Fabian, I've been assigned to support your case.
I appreciate your interest in our products.
This is correct sir, any modification will require a new certification. Also, as you mention, EMVCo is only required for payment solutions.
In order to successfully implement a matching circuit, you will need to follow the next points:
- the Antenna Design Guide that we provide.
- Our new online tool that I'm sure will help you with the correct start of the matching circuit.
- it is also highly recommended to use a VNA for adapting the calculations to a real-world implementation
All of this is shown in the following Video Series: NFC Antenna Design | NXP Semiconductors
I hope this information may have been useful.
Best Regards,
Fabian