energy harvesting

Schuyler · ‎2023-08-11

I am thinking if it is possible to use a reader to read out the values through the ST25DV(Powered mcu by the Veh from ST25dv). Therefore, I bought x-nucelo-NFC7 and stm32l4, and I hope to power L4 through EH energy, but the energy obtained through NFC makes the L4 power lamp light up, but the MCU does not run successfully. What should I do?

Schuyler · ‎2023-08-31

Hi @Mark5_

I have evaluated the product, the minimum energy of the sensor is 50mw, I only tested the EH pin of ST25DV before, but the energy source is not up to the requirements, I plan to add a rechargeable battery and use the energy obtained by NFC to charge the battery, but there is no relevant reference, only know about STEVAL-SMARTAGx.

Schuyler · ‎2023-08-31

Hi @Peter BENSCH

Yes, if I also add a battery and use the energy obtained by NFC to charge the battery, can I achieve the effect of driving the MCU, I only need to use the energy obtained by NFC to drive the MCU to achieve the purpose of sensor acquisition. At present, the energy obtained by the EH of ST25DV cannot directly drive the MCU

Peter BENSCH · ‎2023-08-31

@Schuyler You should not discuss the topic on several threads, because hardly anyone will be able to comprehend this as a problem solution later on.

But to make it clear once again: the EH pin can very well supply an ultra low power MCU such as STM32L. But only if you apply all the necessary power-saving measures and do not connect any power-hungry external devices such as LEDs or your 50mW sensor.

By the way, I consider charging a battery to be a power-hungry application. However, it might be possible to store the harvested energy in a capacitor and then, not simultaneously, use it to supply the STM32L and the 50mW sensor. This is purely a calculation experiment and requires some tricky development.

Good luck
/Peter

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Schuyler · ‎2023-09-01

Hi @Peter BENSCH

Yes, because I use wireless charging technology to collect sensors, and use the energy obtained by NFC to run the MCU is also to make the sensor work normally, which is required by the project, so I would like to refer to the case of how ST company designed NFC wireless charging to run the MCU