Enabling nRF5 DCDC using BLE example

[Nick_RA]

I'm looking at power consumption using nRF52 DK and PPK2. Using the example project ble_app_uart with S112 & Segger Embedded Studio.

Although I've enabled the DC/DC in the config file (I think!) I can't see any change in the power profile: the current consumption is unchanged as I vary the input voltage, it seems to be stuck in LDO mode. What am I missing here?

Thanks

1004.sdk_config.h

[Simonr]

Hi

Are you using the Power Profiler Kit (PPK or PPK2) to do current measurement or some other measurement tool? If using the PPK2, can you share some details on how you've set up the measurement, as the current should indeed decrease if you use the DCDC converter. Enabling NRFX_POWER_CONFIG_DEFAULT_DCDCEN should indeed be sufficient. the DCDCENHV is specific to the nRF52840 and nRF52833 that also have a High Voltage mode where they can be powered with up to 5.5V from I.E. the USB peripheral. There are two regulators on these chips and thus two DCDC regulator circuits.

Best regards,

Simon

[Nick_RA]

(This may be a duplicate as my internet died just as I posted)

As my OP I'm using PPK2 as a source: SB9 cut SB12 bridged and supply to nRF VDD.

So I need at add the nrfx power driver and use that to enable the DCDC?

[mrono]

Nick_RA said:

So I need at add the nrfx power driver and use that to enable the DCDC?

Yes, if you add nrfx_power to your project and call nrfx_power_init() then DCDC will be set according to those defines set in sdk_config.

If you open nrfx_power.c and check how those defines are actually used, you'll see that the only thing needed to enable DCDC is to call: void nrf_power_dcdcen_set(bool enable).

So it is up to you to decide if you want to add nrfx_power or just call that one function without the full driver. Nrfx_power does have other power related features such as the power fail comparator, so check if those are useful to your project as well.

[Nick_RA]

OK that seems to be tha answer, thanks. Actually because of some vagarity with my sdk_config it wouldn't compile in, but I don't want to delve down that rabbit hole just at this moment. I looked at the source and from that just enabled the register for now & it works fine.

NRF_POWER->DCDCEN = true;