I have a NFC chip [Mifare Desfire EV1] which has input capacitance of 17 pF(pico farad).
I got ready-made antenna (Datasheet of Antenna) which has induction of 1.8 uH(Micro Henries). So by simple formulae when i attach chip to antenna it resonates at 28.77 MHz(MegaHertz).
But I need it to resonate at 13.56MHz. So i am thinking of attaching a capacitor.
So my question is :
To resonate at 13.56MHz, Do I need to add 59pF capacitor parallel to Chip and antenna.
Why 59pF :
17pF of chip + 59pF c1 => 76pF which gives 13.56MHz