Power Profiler 2 measures ~15mA after a measurement spike even without a load connected

[Matyee]

Can my Power Profiler 2 be faulty?

It does the following in both source meter and ampere meter mode. I start to measure and it shows some microamps current that's expected from the soft latch circuit. Then I turn on the measured device by latching the circuit and the profiler shows approximately 100 mA of current, that's also expected. Then I turn off the measured device but the profiler does not return to the previously measured microamps, but instead is shows approximately 15mA of current even if I completely remove the load from the profiler. I need to switch modes on the profiler or turn it off and on again to be able to measure the expected microamps again. Turning the power output off and on again or stopping and starting the logging do not fix the issue.

Power Porfiler software verison is: 4.3.1
I cannot tell the firmware version od the PPK2, I could not check it anywhere. But at first connect an update was performed.

Thanks any help in advance.

[Menon]

Hello,

Could you share the firmware version running on the PPK2? You can find this in the logs,try enabling verbose logging in the PPK2 app to help provide the firmware version.

Also, is this an issue you started experiencing recently, or has it been happening since you first began using the PPK2?

Finally, could you try reprogramming the PPK2 using the Power Profiler app to see if that resolves the issue?

Kind regards,
Abhijith

[Matyee]

Thanks for your reply Menon.

The device is brand new. That's why I am exploring whether it is faulty or not. I do not know what to expect.

It is not possible to tell the firmware version even with verbose logging turned on. I managed to upload a new firmware by connecting the tp34 to ground. The logs won't tell the version of the firmware even at upoad time. These are all the log entries with versobe loggin on.

22:38:46.594    [PID:21632] nrfutil-device (version = 2.10.2, platform = x86_64-pc-windows-msvc, classification = nrf-external) invoked with fw-info --serial-number D1127815F5FB --json --log-output=stdout --log-level trace
22:38:46.603    [PID:21632] [ProbeLib] [2025-09-05 20:38:46.604086Z] Opened J-Link DLL at C:\Program Files\SEGGER\JLink_V818\JLink_x64.dll with version 8.18
22:38:46.624    [PID:21632] [ProbeLib] [2025-09-05 20:38:46.625181Z] Opened J-Link DLL at C:\Program Files\SEGGER\JLink_V818\JLink_x64.dll with version 8.18
22:38:46.626    [PID:21632] [ProbeLib] [2025-09-05 20:38:46.626954Z] Found 0 attached J-Link devices
22:38:47.118    [PID:21632] [sdfu] Successfully opened \\?\USB#VID_1915&PID_521F&MI_00#9&110FDD44&0&0000#{86E0D1E0-8089-11D0-9CE4-08003E301F73}. Baud rate: 115200. Flow control: none. Parity: none
22:38:47.150    [PID:21632] [sdfu] Serial port \\?\USB#VID_1915&PID_521F&MI_00#9&110FDD44&0&0000#{86E0D1E0-8089-11D0-9CE4-08003E301F73} closed.
22:38:47.324    [PID:8880] nrfutil-device (version = 2.10.2, platform = x86_64-pc-windows-msvc, classification = nrf-external) invoked with program --firmware C:\Users\PETERS~1\AppData\Local\Temp\26ef931c-203b-4537-824d-db14e3b5d7d8.zip --traits nordicDfu,nordicUsb,serialPorts,usb --serial-number D1127815F5FB --json --log-output=stdout --log-level trace
22:38:47.335    [PID:8880] [ProbeLib] [2025-09-05 20:38:47.335671Z] Opened J-Link DLL at C:\Program Files\SEGGER\JLink_V818\JLink_x64.dll with version 8.18
22:38:47.354    [PID:8880] [ProbeLib] [2025-09-05 20:38:47.355237Z] Opened J-Link DLL at C:\Program Files\SEGGER\JLink_V818\JLink_x64.dll with version 8.18
22:38:47.356    [PID:8880] [ProbeLib] [2025-09-05 20:38:47.356883Z] Found 0 attached J-Link devices
22:38:47.815    [PID:8880] [sdfu] Successfully opened \\?\USB#VID_1915&PID_521F&MI_00#9&110FDD44&0&0000#{86E0D1E0-8089-11D0-9CE4-08003E301F73}. Baud rate: 115200. Flow control: none. Parity: none
22:38:55.244    [PID:8880] [sdfu] Serial port \\?\USB#VID_1915&PID_521F&MI_00#9&110FDD44&0&0000#{86E0D1E0-8089-11D0-9CE4-08003E301F73} closed.
22:38:55.310    All DFU images have been written to the target device.
22:38:56.224    [PID:47976] [ProbeLib] [2025-09-05 20:38:56.224841Z] Opened J-Link DLL at C:\Program Files\SEGGER\JLink_V818\JLink_x64.dll with version 8.18
22:38:56.227    [PID:47976] [ProbeLib] [2025-09-05 20:38:56.227897Z] Found 0 attached J-Link devices
22:38:56.249    Getting serial port options from the persistent store for D1127815F5FB.pc-nrfconnect-ppk
22:38:56.251    Wait For Device was successful
22:38:56.309    [PID:47976] [ProbeLib] [2025-09-05 20:38:56.281124Z] Opened J-Link DLL at C:\Program Files\SEGGER\JLink_V818\JLink_x64.dll with version 8.18
22:38:56.309    [PID:47976] [ProbeLib] [2025-09-05 20:38:56.283979Z] Found 0 attached J-Link devices
22:38:56.314    Getting serial port options from the persistent store for D1127815F5FB.pc-nrfconnect-ppk
22:38:56.341    [PID:47976] [ProbeLib] [2025-09-05 20:38:56.341323Z] Opened J-Link DLL at C:\Program Files\SEGGER\JLink_V818\JLink_x64.dll with version 8.18
22:38:56.344    [PID:47976] [ProbeLib] [2025-09-05 20:38:56.344864Z] Found 0 attached J-Link devices
22:38:56.369    Getting serial port options from the persistent store for D1127815F5FB.pc-nrfconnect-ppk
22:38:56.386    [PID:27036] nrfutil-device (version = 2.10.2, platform = x86_64-pc-windows-msvc, classification = nrf-external) invoked with device-info --serial-number D1127815F5FB --json --log-output=stdout --log-level trace
22:38:56.387    [PID:27036] [ProbeLib] [2025-09-05 20:38:56.386722Z] Opened J-Link DLL at C:\Program Files\SEGGER\JLink_V818\JLink_x64.dll with version 8.18
22:38:56.419    [PID:27036] [ProbeLib] [2025-09-05 20:38:56.419422Z] Opened J-Link DLL at C:\Program Files\SEGGER\JLink_V818\JLink_x64.dll with version 8.18
22:38:56.421    [PID:27036] [ProbeLib] [2025-09-05 20:38:56.422035Z] Found 0 attached J-Link devices
22:38:56.485    Connected to the device with the serial number D1127815F5FB and family: Unknown
22:38:56.791    PPK started
22:38:56.792    PPK opened

Not knowing the firmware version is pretty annoying. The new firmware did not solve the issue.

I am getting very sure that the device is faulty. I did another test when I just sent through in source mode 4.8V of a ~1M ohms resistor. The measured current is ~5 microamps as expected. When I momentarily connect a ~2 kiloohms resistor in parallel. The measured current goes up to ~2.32 milliamps, again, as expected. If I remove the added resistor, the current drops back to the ~5 microamps. Then I connect a 250 ohms resistor in parallel, jumping up the current to ~34 milliamps. That is not expexted. I calculate only ~19 milliamps of current. If I remove the resistor, the current does not go back to ~5 microamps, it shows ~16 milliamps of current. That is approximatly the difference between the measured and calculated values when I measure the 1 megaohms and 250 ohms resistors in parallel.

I again need to switch modes or power off and on the device to stop it measuring this baseline ~16 milliamps.