DCDC - Which peripherals use it other than BLE?

RE: DCDC - Which peripherals use it other than BLE?

Håkon Alseth — Wed, 04 Jun 2025 07:57:48 GMT

Hi,

The DCDC is controlled via hardware. Once enabled in its NRF_POWER->DCDCEN register, the hardware will control the different power states based on consumption.

Here's the place where its set in NCS:

https://github.com/nrfconnect/sdk-zephyr/blob/v4.0.99-ncs1/soc/nordic/nrf52/soc.c#L37

Here's how to set up DCDC in device tree:

&reg {
	regulator-initial-mode = <NRF5X_REG_MODE_DCDC>;
};

And LDO:

&reg {
	regulator-initial-mode = <NRF5X_REG_MODE_LDO>;
};

PS: You can set the register on/off at runtime if desired.

Kind regards,

Håkon

RE: DCDC - Which peripherals use it other than BLE?

snoopy20 — Tue, 03 Jun 2025 21:20:39 GMT

Looked everywhere and can't find it, could I ask for the code which forces DCDC on all the time?

RE: DCDC - Which peripherals use it other than BLE?

snoopy20 — Tue, 03 Jun 2025 17:02:34 GMT

In my case ADC performance worsens when DCDC is enabled, but I'm unsure if it's because DCDC is starting/stopping and the noise from it. I thought I could optimise by forcing DCDC on all the time (using previously supplied code) when I know which peripherals are active and using it.

RE: DCDC - Which peripherals use it other than BLE?

Håkon Alseth — Tue, 03 Jun 2025 16:56:03 GMT

Hi,

The system will use DCDC when it is effective to use it, and automatically switch between LDO operation and DCDC, as described in the POWER chapter of the datasheet:

https://docs.nordicsemi.com/bundle/ps_nrf52810/page/power.html

CPU will use DCDC for instance:

https://docs.nordicsemi.com/bundle/ps_nrf52810/page/_tmp/gluon/autodita/CURRENT/parameters.id_current_cpu.html

Kind regards,

Håkon