Guidance Needed for Measuring nRF52805 Current Consumption (Sleep, TX, RX Modes)

[PKG]

Hello,

I need to measure current consumption on the nRF52805 in sleep, TX, and RX modes. Which sample applications are recommended for each of these measurements? Additionally, please advise if there are any specific considerations or precautions I should keep in mind to ensure accurate current measurements.

Thanks,

PKG

[PKG]

Hi Samruddhi,

Thanks for sharing the link. I’ve made some progress on my side. I’m measuring the sleep current with the system in System OFF mode [sample: System Off ] , and I’m seeing about 0.173 µA. However, the link shows that the expected sleep current for System OFF, no RAM retention, wake on reset is around 0.3 µA.

I’m not sure whether my code is currently using RAM retention or not. How can I configure the system to ensure RAM retention is disabled?

Also, I’m not certain whether the sample I’m using is configured for DCDC or LDO mode. How can I change this configuration in the code?

Sample :

.. zephyr:code-sample:: nrf_system_off
:name: System Off
:relevant-api: sys_poweroff subsys_pm_device

Use deep sleep on Nordic platforms.

My measurement.

Thanks,

PKG

[PKG]

Hi Samruddhi,

Could you help clarify how to switch the configuration from LDO mode to DCDC mode? I’ve tried several approaches, but none of them seem to work on my setup.

Thanks,

PG

[Samruddhi Jadhav]

Hi Praveen,

Apologies for the delay. LDO is used for ultra low power on nRF52 devices. According to what is most efficient, the system will automatically switch mode and that shouldn't cause a difference in result. For reference, you can take a look: Power - Power supply.  In System OFF, RAM retention is not enabled. This is by default. Take a look at fields C-D in: POWER — Power supply. You mentioned observing 0.173 µA. This is quite low but it can also be due to certain factors affecting the measurement such as chip-to-chip variances and temperature. 

Best Regards,

Samruddhi