Testing power off current consumption

[nrbrook]

I'm trying to ensure my firmware goes into power off when it should, and that current consumption is as expected when in power off. However, using PPK2 to measure current on the nRF52 DK, I'm having difficulty getting a low power consumption even with an example project.

Is there an example which specifically demonstrates the lowest possible power consumption in power off? If I edit examples/peripheral/template_project/main.c and add NRF_POWER->SYSTEMOFF = 1; at the start of main, the current consumption is between 2.5 and 15ma. What else do I need to add to that example to get to the 0.3uA specified in the data sheet?

[Simonr]

Hi Nick

Most of our BLE examples in the SDK should support power OFF by the press of a button, but I would suggest checking out the Power Profiling Application, which is intended for doing power profiling of your application, and should be able to enter both system OFF mode and other low power modes without any issues. Please give it a run and let me know if you still see this high current consumption.

Best regards,

Simon

[nrbrook]

Hi Simon,

This doesn't make any difference, current consumption is still the same at power off. It seems unplugging USB makes a big difference in power consumption, but it still only goes to about 600uA. Has the nRF52 DK actually been tested with this example and PPK2 to go to <1uA? If so, perhaps my DK is faulty.

I tried adjusting APP_CFG_NON_CONN_ADV_TIMEOUT in the example to make it enter power off faster, but I see that definition is never actually used, only APP_ADV_DURATION is used, so that's a bug in the example.