nRF52811 and s140 softdevice low power

[Chris Burns]

On the nRF52811 with the s140 softdevice, what is the set of things to do to enter very low power sleep state? The product specification says ION_RAMON_RTC is 1.5 μA. What are the circumstances under which this power state is achieved? What are some of the main things which can cause the chip to use more power?

For things like the BLE stack and GPIOTE events, what is the proper way to shut them down when they're not needed so they use the least amount of power? Here is a quick list of the features we're using:

• BLE (under development but definitely using the s140 to have coded phy)
• app_timer
• GPIOTE when in active state - may not need wake on GPIO

Thanks.

[Kenneth]

Hi,

Check out:
https://devzone.nordicsemi.com/nordic/nordic-blog/b/blog/posts/optimizing-power-on-nrf52-designs

In general the entire architecture is event driven, meaning that it will enter low power idle current as long as you have not actively started any activity (e.g START task of uart, twi transfer etc.). If you have started activity and want to enter low power mode again you should stop the activity (e.g. STOP task of uart, twi transfer etc.).

Enabling or configuring a peripheral does not cause any current by itself.

You may also find this useful:
https://devzone.nordicsemi.com/nordic/nordic-blog/b/blog/posts/nrf52-online-power-profiler

Best regards,
Kenneth

[Chris Burns]

Thanks for your help!