BM833 energy saving

[RichardHdrd]

Dear forum,

I want to achive low energy consumption for a BM833 (with crystal).

From the following thread, I could deduct, that running the softdevice, an average of 300+ uA is required:

https://devzone.nordicsemi.com/f/nordic-q-a/10425/possible-to-shutdown-soft-device-or-ble-after-init-to-achieve-low-power

Now I could follow the instructions to shutdown the HF-Clock, as suggested, but I could read:

"The SoftDevice does not stop the LFCLK when it disables because other modules may use it (like app_timer)."

This, in reverse, could mean that stopping LFCLK might render the app_timer unusable?

I need to be able to "relaunch" the softdevice (S132) periodically to achieve periodic transmissions (send and/or receive) and currently, I'm using also timers to read from peripherals.

How would I have to proceed to achieve that goal when, at the same time, switching off the LFCLK to achieve 2uA consumption?

Can anyone give a code example?

Best regards,

Richard

[RichardHdrd]

Hello Vidar,

Sorry to continue the thread from here, but the forum doesn't allow me to respond from your last suggestion ("enable the Softdevice and use the idle_state_handle().").

If I do, as you suggest, with all LFRC clock-configuration as suggested, I see an average current of 300+ uA (the same 300+ uA that were observed, before I changed the clock settings in sdk_config.h for LFRC, as you suggested below).

So, the question still is, how to get the current down to the famous 2.2uA (or at least significantly below 300+ uA)?

Best regards,

Richard

[Vidar Berg]

RichardHdrd said:

If I do, as you suggest, with all LFRC clock-configuration as suggested, I see an average current of 300+ uA (the same 300+ uA that were observed, before I changed the clock settings in sdk_config.h for LFRC, as you suggested below).

Which of the suggested clock configurations did you select, the LFXO or LFRC?

RichardHdrd said:

So, the question still is, how to get the current down to the famous 2.2uA (or at least significantly below 300+ uA)?

It must be caused by something else if you selected one of the clock sources above.