Achieving 3.16µA System ON Sleep in Zephyr

RE: Achieving 3.16µA System ON Sleep in Zephyr

Simon — Fri, 02 Oct 2020 17:57:54 GMT

Do you also see 3.2uA after letting it run for a while?

RE: Achieving 3.16µA System ON Sleep in Zephyr

Marciano-PL — Fri, 02 Oct 2020 17:02:20 GMT

I measured the current from the provided hex file, and I'm seeing ~3.2µA between ads, so it looks like there must be something wrong with my firmware. I'm not exactly sure what though.

RE: Achieving 3.16µA System ON Sleep in Zephyr

Simon — Fri, 02 Oct 2020 13:40:31 GMT

Okay, then your measurement tools are probably good. I guess the problem is a bad chip.

Could you do one more test to confirm this, first program the power profiler hex I uploaded here (nrfjprog --program ble_app_pwr_profiling_pca10056_s140.hex --sectorerase). It will start in System OFF, and you should see a current consumption of around 0.4uA.

Then, to figure out if the high current consumption is due to the FW or a bad chip, press button 2, which will start non-connectable advertising. Measure the current between the advertising event (chip is in System ON idle with LFXO, RTC and full RAM). If you see a current consumption higher than 3.16 then, there is something wrong with your chip. Check out the documentation for the sample if needed: Power Profiling Application

devzone.nordicsemi.com/.../7587.ble_5F00_app_5F00_pwr_5F00_profiling_5F00_pca10056_5F00_s140.hex

I have not been able to test to measure the current with this hex to confirm that everything is all good. I will on Monday.

Best regards,

Simon

RE: Achieving 3.16µA System ON Sleep in Zephyr

Marciano-PL — Wed, 30 Sep 2020 20:26:20 GMT

With DCDCEN0, LFCLKSRC XTAL, and all RAM sections off, I observe a current of 0.4µA.

RE: Achieving 3.16µA System ON Sleep in Zephyr

Simon — Tue, 29 Sep 2020 14:42:54 GMT

There might be an offset on your measurements. Could you test a sample which puts the chip into System OFF (e.g. the Power Profiling Application starts in System OFF, but requires you to install the nRF5 SDK) and see what the current consumption is then? If you get more than 300nA, then there is an offset.

If you see a linear increase in current, you probably have a bad chip. If the there is a constant offset, the cause is probably due to leakage/measurement error or something in FW that causes a higher consumption.

Best regards,

Simon

RE: Achieving 3.16µA System ON Sleep in Zephyr

Marciano-PL — Mon, 28 Sep 2020 17:07:25 GMT

Those links are exactly how I have been using the PPK. I tried out your hex file and these are my results (~411µA)

I tried the sample you described in a previous comment and also achieved ~4µA of current consumption.

RE: Achieving 3.16µA System ON Sleep in Zephyr

Simon — Fri, 25 Sep 2020 08:07:37 GMT

Just forget what I said about putting SW6 to nRF ONLY, it should not be necessary. I'm using another tool for measuring.

Follow these three:

Test the aplication I described in my last reply, or the hex file provided below.

devzone.nordicsemi.com/.../zephyr.hex

What current consumption do you see then?

Best regards,

Simon

RE: Achieving 3.16µA System ON Sleep in Zephyr

Marciano-PL — Wed, 23 Sep 2020 16:04:56 GMT

Hi Simon, thank you for your reply!

I've gone ahead and tried your solution, but when my DK SW6 switch is in the nRF ONLY position, I cannot talk to the PPK. How did you get around this? I think SW6 might be the missing piece to my puzzle, but I haven't been able to verify yet.

Is there anything else I must do to make it work?

RE: Achieving 3.16µA System ON Sleep in Zephyr

Simon — Tue, 22 Sep 2020 08:54:09 GMT

I was able to get the current down to 3.18-3.19 uA in NCS v1.3.0. I did the following:

Set CONFIG_SERIAL=n in zephyr\samples\basic\blinky\prj.conf
Built and flashed the blinky example:
- cd zephyr\samples\basic\blinky
- west build -b nrf52840dk_nrf52840
- west flash
Attached the PPK to the nRF52840 DK
Set SW6 to nRF ONLY
Opened the Power Profiler app and started sampling

Best regards,

Simon

RE: Achieving 3.16µA System ON Sleep in Zephyr

Marciano-PL — Fri, 18 Sep 2020 22:34:55 GMT

I've tried to match the conditions in Table 13: Current consumption scenarios, common conditions as much as possible to make it easier to narrow down the differences.