Recommended smartphones for ST25DV64K

[JHern.18]

Hello,

We have experiended RD/WR problems with standard smartphones.

Is there any list of recommended smartphones for operating with ST25DV64K?

Regards, Ramon.

[JL. Lebon]

​Hello,

It depends on what if your definition of "operating with ST25DV64K"

We can distinguish two kind of operating modes:

• native
• proprietary application

Native support is when you want your smartphone to automatically read an NDEF message in your NFC tag when you tap it. This operation is entirely managed by the operating system of the phone.

Only a few "native" operation are available on smartphone as of today:

• read an URL in tag and open a web browser
• read an email address in tag and open the mailing application.
• read a wifi or a Bluetooth SSID and propose pairing
• read a virtual business card and open your contacts.
• ...

You can also communicate with the NFC tag with a proprietary application. In that case, the communication is not handled automatically by the operating system, but by the application.

This is what you do when you use the ST25 NFC tap application from the play store. The application allow to communicate with the NFC tag and to do plenty of actions you cannot do "natively".

If your target is native operating (basic NDEF reading):

• ST25DV64K is perfectly supported by iPhones.
• Android phones with android version up to Android 8 (Oreo) included does not support tags with large memory very well (memory > 8kbits). Only a few of them will be able to operate natively with ST25DV64K.
• Full support is available starting with Android 9 (Pie).
• if you don't need more than 4Kbits of memory and target Android < 9, you can use the ST25DV04K , if you need more memory  and Android < 9, you can use the M24LR64-E (this last one is supported from android 6 to 9).

If your target is not native support and you plan to develop your own application, then any Android phone with NFC feature will do it.

Hope this clarify the support of ST25DV64K in phones.

Best regards.

[JHern.18]

Hello JL.

Thanks for your detailed answer.

Not native, we are not using NDEF structures. The operating mode is handled by using propietary application.

We are just writing and reading bytes in memory with the phone.

We have found problems with some commercial phones, indeed, when the board ( where ST25DV64K is mounted along with its antenna ) is powered. Have you experienced any similar issue?

We have detected a lot of problems with commecial phones and the only phone that provides reliable Writing process is a rough phone by BlackView. Some models of BlackView use the ST21NFCD as reader/writer.

Do you think the problem is due to NFC chipset used in the phone or antenna performance?

Do you have a list of phones which includes the ST21NFCD as NFC chipset? apart form Alcatel 3V , which NFC version is not available in Spain.

Regards, Ramon.

[JL. Lebon]

​Dear Ramon,

There is no report and I have no experience of particular problems with commercial phones.

The product has been successfully tested on many smartphones from major brands (Samsung, Huawei, Google, Sony, LG, Oneplus, Xiaomi, Apple...). Difficult to list them all.

Those phones embed various NFC controllers from different IC manufacturers.

May I ask you if you face issues with your own application board/antenna or with ST demo board ?

Best regards.

[JHern.18]

Hello,

Thanks for your answer. The detected issues are found in our own application.

How could I compare the performance between your demo board and our application? by reading distance? by measuring some parameter on the antenna?

Regards, Ramon.

[JHern.18]

Hi again,

Do you have any idea which phones use the ST21NFCD ?

Regards, Ramon,

[JL. Lebon]

​Dear Ramon,

Sorry for my late reply.

�? don't have a list of phones using ST21NFCD controller. Anyway, ST25DV-I2C is compatible with any smartphone, not only with smartphone using NFC controllers from ST, so NFC controller is probably not the good place to start debugging.

First thing I would suggest to do is to check your antenna design.

We have an application note (AN2972) to help on antenna design at the following link:

https://www.st.com/content/ccc/resource/technical/document/application_note/bc/ac/13/fe/69/fb/49/8a/CD00232630.pdf/files/CD00232630.pdf/jcr:content/translations/en.CD00232630.pdf

In chapter 4 of this application note, there is detailed explanations on how to measure your antenna tuning. I suggest as a first step of debug to measure your antenna tuning following the method described in this application note.

Best regards,

JL.