Ask questions and find answers on ST25 NFC/RFID tags and readers, including connectivity implementations and antenna design.
Hello.For example, on the datasheet of ST25R200, on page 10, it shows 2 capacitors between pins VDD_A and GND_A, but on page 13 it is not shown the recommended values of these 2 capacitors.Would they be 2.2uF and 100nF, or 1uF and 100nF, for example?...
Hello I am beginning the electrical schematic with the ST25R200. I saw on the datasheet, and here:https://eds.st.com/nfc-tuningcircuit/I saw that there is the single-ended and differential ways / circuits to drive the antenna.The differential circuit...
Hi,Comparison of STEVAL-ST25R3916B UM3033 [pg 22] & ST25R Antenna Matching Tool...Specifically the matching networks show a difference in location of parallel tuning capacitor relative to antenna connection. UM3033 antenna matching + filter [above]. ...
Hello people. In 2020, our company made a PCB prototype (designed by me) which included a chip " ST25R95-VMD5T ". Our results were not good, but maybe this was due to a poor filter circuit and due to a poor matching circuit. The tag reading distance ...
Hi, I'm trying to measure X-Nucleo-nfc03a1 with VNA: i got completely different values for C11 C22 and C2 as is on nucleo board. I understood something wrong? and when I remove Resistors 330ohm, inductor and 4 100pF capacitors I got like:
Hello,I am using the ST25R3918 controlled by an MCU via RFAL, operating in NFC-F / FeliCa card emulation mode.I am monitoring the efd_o bit (bit 6) of the Auxiliary Display Register (Address: 31h) to detect when the board approaches an external reade...
Hello,I have an ST25DV64KC chip and I’m having a problem with I2C read/write. The I2C bus is running at 100 kHz and is functional (communication with another sensor, SHT, on the bus works fine). I am also able to communicate with this NFC chip - I ca...
I have successfully integrated a ST25R100 NFC reader with an ST25DV04K tag. Reading and writing data works perfectly.But once you enclose the system in its housing, writing doesn't work, even though reads still succeed.I presume this has something to...
Hi, I have been working on a project that is based on the ST25R3911b Discovery Board including building prototype firmware from the discovery kit's firmware. I have made sure not to edit any of the RFAL or HAL library files.Recently I had brought thi...
Hi everyone,I’m trying to interface an ST25R100 NFC reader with my MCU, and I’m having trouble reading ISO15693 tags. My initialization seems to work, but I never get any response from the tag. I’m hoping someone can spot what I might be missing.This...