2026-01-30 4:47 AM
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 was very small, and the prototypes were not fixed (filter and matching), and we abandoned the project.
So in the same year of 2020, we were planning to make another PCB prototype, but then using the chip " ST25R3911B-AQFT ", with the intention that the reading of tags could reach a bigger distance, but we ended up not doing this prototype in 2020.
Now, it's 2026, and we plan to make a PCB prototype, very simple. And our initial choice was the " ST25R3911B-AQFT ". I would like to ask if there are more recent chips than this, possibly one chip that can reach a bigger reading distance than this " ST25R3911B-AQFT ", or that reaches the same distance reading, but that has more recent technology.
Remembering that this time we will first design a PCB coil / antenna, produce a bare PCB of it, and measure its parameters (measured by a third party). If I remember, there are 4 parameters, like the self-resonating frequency, parallel resistance at the resonating frequency, inductance @ X MHz, and DC resistance @ X MHz. We will get the measurements, and use them on the online calculator of ST that calculates the values of all components of the entire circuit between the antenna and the chip (filter and matching).
The chip " ST25R3911B-AQFT ". I would like to ask if there are more recent chips than this, possibly one chip that can reach a bigger reading distance than this " ST25R3911B-AQFT ", or that reaches the same distance reading, but that has more recent technology.
Regards,
Jeferson Pehls.
Solved! Go to Solution.
2026-01-30 6:34 AM - edited 2026-01-30 6:34 AM
Hi Jeferson,
new reader chips are available in the ST25R family
See the products selector on https://www.st.com/en/nfc/st25-nfc-readers/products.html for full details.
If your application does not use NFC-F nor Card Emulation, ST25R200 is the right choice for your application. The following tools are available for this device:
Rgds
BT
2026-01-30 6:34 AM - edited 2026-01-30 6:34 AM
Hi Jeferson,
new reader chips are available in the ST25R family
See the products selector on https://www.st.com/en/nfc/st25-nfc-readers/products.html for full details.
If your application does not use NFC-F nor Card Emulation, ST25R200 is the right choice for your application. The following tools are available for this device:
Rgds
BT
2026-01-30 8:34 AM - edited 2026-01-30 9:16 AM
Hello Brian.
The ST25R200 is 1200mW. It is 1200mW of RF power or 1200mW of consumption?
What is the typical RFID power and typical consumption at 3.3V?
Are there ways to reduce consumption? Like an IRQ pin?
Regards.
2026-01-30 9:22 AM
Hi Jeferson,
the values are extracted from the Output Power column of the product selector.
As the reading distance seems to be an important criteria for your application, the STEVAL-25R200SA
could be used to evaluate this parameter. It is a form factor board with different antennas.
Rgds
BT
2026-02-04 1:45 AM
Hello Jeferson,
please be aware that ST has released another product this week.
So the complete list would be:
Application notes for the ST25R210 will become available in the next weeks.
The output power is dependent and mainly controlled via the antenna matching (target matching impedance).
Dependent on the power you want to spend, (e.g. batterie powered device, ...) the target matching impedance is chosen to fit this requirement.
please let us know, if you have additional questions.
BR Travis
2026-02-04 5:16 AM
Hello Brian.
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 is bigger, it has more components.
So what I ask here is about these difference (single-ended / differential), if using the single-ended scheme it's possible to reach the same tag distance reading of the differential scheme. Because our PCB is relativelly small in space available. Are there more advantages on using the differential circuit compared to the single-ended circuit?
Regards
Jeferson Pehls.
2026-02-04 5:34 AM
Hi Jeferson,
as this thread is already in Replied state, I would suggest to start a new thread related to the single ended vs. differential antenna.
Thanks in avance
BT