nRF only mode on nRF52840DK

[krajiiva]

Hello,

I have following problem.

I use the nRF52840 DK and want to run it in nRF only mode, so I have the minimum power consumption. If I set the DK to low power mode with "nrf_pwr_mgmt_run()" I still have a current consumption of about 1.4mA. To get into the nRF only mode I set SW10 to ON, SW9 to VDD and SW6 to nRF only. Furthermore I operate the DK via the P21 with an external voltage. Nevertheless I can't reduce the current consumption into the uA range. Did I forget to configure something on the DK? Can you tell me what I have to do to further reduce the current.

Thanks already.

[Jørgen Holmefjord]

Hi,

How do you measure the current? Do you measure current on P22/P23, or do you measure the current going into the board through P21? Current on P22/P23 pins are for the nRF power domain only, it does not include the current from interface MCU, LEDs, etc.

What application are you running on the DK, and which SDK version are you using? Calling nrf_pwr_mgmt_run() will not necessarily give you low current consumption, this depends on which modules are enabled/running in the background. 1.4 mA (given that this is consumed by the nRF itself), sounds like the EasyDMA current. This is often enabled by UARTE in RX mode or SAADC peripheral enabled.

Best regards,
Jørgen

[Jørgen Holmefjord]

Hi,

Sorry for the slow response on this matter. I'm not able to build the application, as it seems to include some custom drivers.

If you have not yet resolved this issue, can you please post the full project, including the custom driver implementations?

Best regards,
Jørgen