how can adjust to dozens of uA (with freertos)

[canan]

Chip: NRF52832; SDK: 13.0.0 Softdevice: s132_nrf52_5.0.0; Routines: ble_app_hrs_freertos; Configuration: Minimum system board, broadcast interval 1000ms; Question: Broadcast power consumption of about 800uA or so, power consumption is too high, how can adjust to dozens of uA (with freertos);

[Arnaud Nelissen]

All the FreeRTOS examples I tried (from SDK 12 to 14 and associated softdevices) showed up a 800µA current consumption. I managed to get 30µA with a NON FreeRTOS example (ble_app_template). I can't see which peripheral is running, as the examples do not start one... I opened a case on MyPage.

Thank you for your help.

[canan]

The minimum system board is PCA10040 V0.9.0, ammeter in series with P22 (nRF current measurement), the freertos routine (ble_app_hrs_freertos) in SDK V13.0.0 is 800uA (1000ms broadcast interval);

[Susheel Nuguru]

updated(2 July 2017)

Use SDK 13 and replace the file given in this thread. It is best not to post files in many threads as we might loose track and forget to update the thread.

[Susheel Nuguru]

I have tested this myself and many other customers confirmed that now SDK FreeRTOS example takes about 100uA instead of 800uA after this fix.

[labi]

Hi Aryan,

Im looking into reducing power usage in my application as well, but havent had any luck reducing the current lower than around 800uA. Here's what I've done so far:

1. Downloaded SDK 13.0.0 / softdevice 4.0.2 - ble_app_hrs_freertos consumes about 8mA - NRF toolbox cannot connect to device - connection keep disconnecting

2. Set NRF_LOG_ENABLED to 0 in the same project - current went down to 800uA - NRF Toolbox can now connect reliably

3. Applied above fix provided by you - current is still at 800uA

4. Changed to Softdevice 4.0.4 - no change in current - Connection stays OK

5. Disabled Idle hook - no change in current - connection stays OK

6. Changed to Softdevice 5.0.0-3.alpha - Current went up to 6.5mA - NRF Toolbox cant connect to device any more

Any Ideas what Im doing wrong or how I can lower the current down to 100uA as documented here?

My hardware setup is NRF52-DK (used as a debugger) ---> Sparkfun NRF52 breakout board as target

I'm using armgcc compiler on Ubuntu Linux

All current measurements listed here are measured using a Fluke 87V True RMS Multimeter measuring current going into the target board, with NRF52-DK switched off.

Any help would be very much appreciated.

Thank You,