How about NFC Wireless Charging

[Schuyler]

I understand that I have exited the NFC WLC function and I currently have X-NUCLEO-NFC07A1. How do I charge the WLC-Listener using the battery charging function shown in the legend?

[Rene Lenerve]

Hi @Schuyler ,

NFC WLC is a specification defined by the NFC Forum, they have defined a communication protocol via NDEF messages in order to negotiate between Poller and Listener the power to charge a battery and is not intended for other applications. Refer to the NFC Forum web site for more information on that topic.

As explain earlier, ST25DV (as other tags) risks overheating if the Poller increases its power. So for WLC you need Hardware components that protect the tag and recover excess energy for the charger (first stage in your screenshot "Rectifier and Protection").

Hope this can help you.

Kind Regards.

[Schuyler]

Hi @Rene Lenerve 

So if I want to use NFC to achieve energy and information transmission, but the current use of EH pin output is not enough to provide large energy, can not drive the MCU to complete other tasks, then what should I do? I hope you can give me some specific suggestions so that I can complete this task.

[RhSilicon · Accepted solution]

Coin type lithium battery (CR2032(3V), A23(12V)) is generally used for general purpose remote control such as garage door. If your project needs more uptime from the MCU, you might be able to use a user replaceable battery if it can't recharge the battery via NFC.

[VGros.3]

What I understand with all your replies, is that NFC WLC (wireless charging) is not a mature technology. There isn't any application note and ST25 datasheet does not give any information about this.

For the wireless charging part of my project, I think I will use Qi technology.

Thanks

[Schuyler]

Hi @RhSilicon 

As you know, I need to use the energy collected by NFC to run the MCU to complete other tasks, but I can't run the MCU properly only with less than 10mw energy of EH, so do I have any other way to complete this project?

Thanks

[Schuyler]

Hi @VGros.3 

Yes, I also think so, because ST company does not have any relevant information, I can not find information from it. But I need to use NFC to complete the transmission of information and energy, not only to complete the task of power supply, but also to transmit signals.

[Schuyler]

Hi @VGros.3 

Thanks for the Pointers! I want to ask about the specific case of NFC battery charging? The introduction of NFC to obtain energy for battery charging and MCU power supply

Thanks

[Schuyler]

Hi @Rene Lenerve 

I would like to know that relevant products have been mentioned in the introduction of NFC WLC. ST’s ST25R NFC readers and ST25DV-I2C NFC tags enable the design of NFC wireless charging solutions. Integrated with additional ST components, such as an STM32 microcontroller, these ST25 readers and tags allow you to design a complete NFC wireless solution.So I can't do that?

[Berenice BENVEGUDA]

Hello,

The NDEF protocol  is described in WLC NFC Forum standard. You have to subscribe to NFC Forum standard to get it.

As mentioned in other posts, WLC technology requires specific support to your application. Please contact your local sales office to get support

Best Regards,

BB