ST25R3916 filter: L and C

[mossaab daiki]

Hello, I am using the ST25R3916 reader. looking at the schematic of the filter and matching circuit I notice that the cutoff of the filter is lower than 13.5 M. I would like to double-check the L and C of the filter : 270 nH and 680 pF , thanks

[Travis Palmer · Accepted solution]

Hello Daiki,

Yes, your understanding is correct.

The EMI filter consists of L=270nH and C=680pF. You can find the component values in UM2358 Rev 4, page 28/31.

Further details about the antenna tuning of the ST25R3916 can be found in AN5276 Antenna design for ST25R3916, ST25R3917 and ST25R3920 devices 3.0.

br Travis