Hi,

I designed one NFC antenna for NXP 7210 chip. as specified in the NXP antenna design guide i made the antenna and maching circuit with 70 Ohm impedance. Measured impedance data attached with thread. The nfc working in the frequecncy 13.56 MHz. All 13.56 MHz NFC tags are detecting execpt one specific tag. The RXN pin probed for 3 tags in time domain, The wave form is also attached with the tread.

-AK.
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