reducing power of HRS sample

[Johan.h]

I have a BLE sensor device that works, but draws about 4 mA, much higher than needed. In order to learn how to reduce current, I tried to compile and run the HRM sample code and check current on my device hardware.

It also draws about 4 mA, as long as it is advertising. I tried to change some parameters such as adv. interval etc. but could not reduce power to the required level.

I would like to get to an average consumption of 50uA, using very low data rate, it will be ok to advertise once in 5 seconds or even less.

When connected, it also should send data only every500 ms or so and keep very low power.

What steps should I take to get there? (After advertising is over, the consumption drops to less the 1 uA, so my hardware is OK, I guess.)

Thanks.

[Simonr]

Hi

What SDK and SDK version are you using for development? How to get minimize current consumption depends on the SDK used. If you want to advertise as rarely as every 5 seconds, I think it shouldn't be a problem at all to go to sleep in between advertisement in order to save power. Same goes for between transmissions in a connection. You can use the Online Power Profiler for BLE to get some estimations on what you can expect at different advertising intervals, TX powers, etc.

Best regards,

Simon

[Johan.h]

I am using SDK_15. I removed all the timers that I can see, by not calling application_timers_start(), set the adv interval to 5 seconds. Using PPK2, I can see the adv peak current every 5 seconds, but still see some activity every 2 seconds which I can't stop. Any idea what can it be? (Average current now about 450 uA).