Power Profiler doesn't measure anything.

[soointerested]

I have a NRF52840 DK, with a pca63511 power profiler kit purchased just a few days ago from Mouser.  I am trying to use the power profiler kit with version 2.3.1 of the power profiler app installed from nRF Connect v3.4.1 on MacOS 10.15.2.  I'm connected to the DK via USB directly to my computer.  Or more precisely through a USB-C to USB 3 adapter since I have a Macbook Pro 16in with no regular USB ports.

I cut the SB_40 (VDD) and SB_41 (VDD_hV) traces on the DK and was able to measure 400nA sleep current through the two VDD pins next to the trace using the another low current measuring device called the CurrentRanger.  But I would like to use the power profiler kit.

Switch positions are as follows:

• DK: nRF power source = VDD
• DK: Power = ON
• DK: SW6 = Default
• Power Profiler: Power Select = DK

I have the blinky example flashed, but nothing happens when I connect the USB port because the power trace has been cut.  When I attach the power profiler the LEDs start flashing in sequence as expected.

What is not working is that no LED lights up on the power profiler board.  I can connect to the serial port in the power profiler app on my computer, but no readings are displayed.  When I click "start" the buffer progress bar shows 113.8s and does not fill up as time passes.  The avg,max,charge values are stuck at zero.

I can click Power ON or Power OFF but it doesn't seem to have any effect.  The DK LEDs continue to flash regardless.

What am I doing wrong?  Thanks!

[Jørgen Holmefjord]

Hi,

The PPK is mounted on top of the DK?

Is the "DUT select" switch in the DK position? Is the COM switch in DK position (if you have not removed the tape, it should be). Did nRF Connect Power Profiler app ask you to flash the PPK when you connected to the COM port of the DK?

Best regards,
Jørgen

[soointerested]

Thank you for the reply!  Yes, DUT select and COM switches are both in DK position.

No, the power profiler app did not ask me to flash the PPK.

[Jørgen Holmefjord]

Can you try to erase the firmware on the PPK, using "nrfjprog --eraseall" command? Then open nRF Connect Power Profiler app and check that it asks to flash the firmware again.

[christos profentzas]

Hi,

I have the same setup and the same issue, after reading the documentation I realize that I have not cut the bridge SB40,
https://infocenter.nordicsemi.com/index.jsp?topic=%2Fug_nrf52840_dk%2FUG%2Fnrf52840_DK%2Fprepare_board.html

After cutting the SB40 works for me.

However, in order to reprogram the board, I need to put a jumper on P22. Then, if I want to use the power profiler again I need to remove the jumper.

It end-ups to these steps: 1) remove power profiler, 2) put the jumper 3) flash new program 4) remove jumper 5) put the power profiler back!

I hope there is a better way to do it...

[Jørgen Holmefjord]

christos profentzas said:

After cutting the SB40 works for me.

That is a good point. When I tried this before, the PPK showed a high current, but it may have changed for more recent software versions.

christos profentzas said:

However, in order to reprogram the board, I need to put a jumper on P22. Then, if I want to use the power profiler again I need to remove the jumper.

It end-ups to these steps: 1) remove power profiler, 2) put the jumper 3) flash new program 4) remove jumper 5) put the power profiler back!

This is correct, you need to close it with a jumper if the PPK is removed from the DK. It is also possible to program the DK by switching the COM switch over to EXT and then back to DK after programming. Another option is to use a second DK with a 10 pin cable between Debug out of the external DK and the Debug in on the PPK. In this configuration, the COM switch needs to be in EXT position all the time.