energy harvesting

[kayarael]

Posted on June 13, 2016 at 11:58

Hello,

I'm starting with nucleo L476RG , MEMS and NFC02A1.

I try to write MEMS data to nfc tag and its work.

My problems is when i try to use energy harvesting mode, it  doesn't work and i don't know why. I use the exemple within the nfc cube but it doesn't work.

You can look the main function and Enable_EnergyHarvesting below

Can someone help me please?

Best regards

#m24lr-harvested-power

[Rene Lenerve]

Posted on July 01, 2016 at 14:32

Hello Daisy,

Can you explain what exactly doesn't work in your application?

The example you mention only enables energy harvesting feature on the M24LR and configures it to supply max 6mA (see

http://www.st.com/content/st_com/en/products/memories/nfc-rfid-memories-and-transceivers/dynamic-nfc-rfid-tags/m24lr-series/m24lr04e-r.html

for Energy Harvesting characteristics). Then you need to connect, for example a low power led, between the Vout pin and Vss pin(on the X-NUCLEO-NFC03A1 board Energy_Harvesting pin and ground), and when you approach a reader the LED should light.

Kind Regards

[kayarael]

Posted on July 11, 2016 at 14:57

Hello,

I don't have a low power LED but i try with a the low power nucleo L476RG and that LED2 is turn off. When i try to do the same wuth the M24LR discovery, the LED  on the nucleo L476RG turn on. I just link the two board throw  the  power GPIO.

So i don't understand where i fail with the NFC02A1.

Can you help me please?

[Rene Lenerve]

Posted on July 25, 2016 at 10:17

Hello,

To power the Nucleo board you need first to make some Hardware configuration as described in the

http://www.st.com/content/st_com/en/products/ecosystems/stm32-open-development-environment/stm32-nucleo-expansion-boards/stm32-ode-connect-hw/x-nucleo-nfc02a1.html

:

2.2 Power Supply and GPIO options

2.2.1 Power Supply option

The X-NUCLEO-NFC02A1 board contains the M24LR04E chip. In addition to basic functionalities (NFC & I2C) of this dynamic NFC/RFID tag IC, some jumpers on board permit to configure extra features.

• ST1: selects the M24LR power source: external (Nucleo Board power supply) or M24LR energy harvesting

• ST2: M24LR energy harvesting is used to power Nucleo STM32 board.

If this feature is used, user has to make sure that the Nucleo STM32 board can accommodate this power configuration (SB2&SB12 removed).

The power delivered from energy harvesting is highly dependant of the field supplied by the reader (smartphone, it can be different from each smartphone or reader and from the position of the reader). There are four configurations for Energy Harvesting detailed in the table 126 from the

http://www.st.com/content/st_com/en/products/nfc/st25-nfc-tags-readers/dynamic-nfc-tags/m24lr-series-dynamic-nfc-tags/m24lr04e-r.html

. You need to know the power consumption of your system to configure the M24LR.

Hope this will help you,

Kind Regards.

Have a nice day.