PPK ampere mode high peaks

[maya_sa]

Hello, 
I ran the nrfconnect (ver 3.7.1) in Power Profiler (ver 3.1.3) in BLE advertising.

When I run the source mode on 3000V I get normal peaks  (20mA), however when I run the Ampere mode with the same voltage I see peaks of 45-50 mA.

On a different PC (same PS and cable , same nrf version and power profiler version) both Ampere mode and Source mode show the same values (as they should).

Thank you for your help.

[maya_sa]

Hi , Windows 10 pro (on both pc), 64 bit 

And yes I have followed the setup in the same way both times

[JONATHAN LL]

Then it could be noise from the USB port, do you consistently get higher spikes on all USB port on the on PC with higher spikes?

Regards,
Jonathan

[JONATHAN LL]

Can you provide a plot and log from the test with "bad" PC?

Does the "bad" PC use AMD, if it is a AMD computer then could you try a USB 2.0 hub and see if the problem still occurs. 

Regards,
Jonathan

[maya_sa]

the bad PC dosnt use AMD 

Thank you

[JONATHAN LL]

Could you provide the log also:


you can access it by clicking on the open log file button

Regards,
Jonathan

[maya_sa]

The log:

2021-10-27T11:34:07.732Z INFO Application data folder: C:\Users\maya.sagalin\AppData\Roaming\nrfconnect\pc-nrfconnect-ppk
2021-10-27T11:34:07.814Z DEBUG App pc-nrfconnect-ppk v3.1.3 official
2021-10-27T11:34:07.814Z DEBUG App path: C:\Users\maya.sagalin\.nrfconnect-apps\node_modules\pc-nrfconnect-ppk
2021-10-27T11:34:07.814Z DEBUG nRFConnect 3.7.1 is not supported by the app (^3.6.1)
2021-10-27T11:34:07.814Z DEBUG nRFConnect path: C:\Users\maya.sagalin\AppData\Local\Programs\nrfconnect\resources\app.asar
2021-10-27T11:34:07.815Z DEBUG HomeDir: C:\Users\maya.sagalin
2021-10-27T11:34:07.815Z DEBUG TmpDir: C:\Users\MAYA~1.SAG\AppData\Local\Temp
2021-10-27T11:35:37.354Z INFO Validating firmware for device with s/n 000601008155
2021-10-27T11:35:37.662Z ERROR Error while setting up device 000601008155: Error occured when close opened device. Errorcode: CouldNotOpenDevice (0x4)
Lowlevel error: LOW_VOLTAGE (fffffff4)

2021-10-27T11:35:37.662Z INFO Deselecting device
2021-10-27T11:35:39.662Z INFO Validating firmware for device with s/n 000601008155
2021-10-27T11:35:39.935Z ERROR Error while setting up device 000601008155: Error occured when close opened device. Errorcode: CouldNotOpenDevice (0x4)
Lowlevel error: LOW_VOLTAGE (fffffff4)

2021-10-27T11:35:39.935Z INFO Deselecting device
2021-10-27T11:35:46.384Z INFO Validating firmware for device with s/n E45F82AF9DC5
2021-10-27T11:35:46.393Z INFO Opening device with s/n E45F82AF9DC5
2021-10-27T11:35:46.638Z INFO Trigger length updated to 10 ms
2021-10-27T11:35:46.674Z INFO PPK started
2021-10-27T11:35:46.707Z INFO PPK opened
2021-10-27T11:35:48.669Z INFO Mode: Ampere meter
2021-10-27T11:35:48.682Z INFO DUT ON
2021-10-27T11:35:49.729Z INFO Sampling started
2021-10-27T11:36:10.911Z INFO Sampling stopped

[JONATHAN LL]

Need to ask you for one more thing, could you click on the save/export and save as PPK and csv and share both. 


Regards,
Jonathan

[maya_sa]

ppkexports.zip the ppk and csv are in this zip , didnt let me upload separately 

[JONATHAN LL]

Thanks, 

Seems to be a strange artifact, could you provide some more info on the two computers. 

Are both intel computers?

And can you test with a USB 2.0 hub ?

Regards,
Jonathan

[maya_sa]

I have tested with a usb 2.0 hub and no change in the values
both pc's are intel computers 

[JONATHAN LL]

Hi, thanks for the information so far, i dont have a solution for you, but i do have some more options for you to try and a questions. This is a very unique issue you have come across and it is very interesting for us to debug. 


Was the USB hub you used powered externally also, or just from USB on computer?

Could you use a USB charger and connect a cable to the "USB power Only" connector. Want to check if the computer you are using has some supply irregularities from the USB ports. 


Regards,
Jonathan

[maya_sa]

The USB hub was powered from the USB on the pc.

I have used an external USB charger and connected to the "USB power only" connector.

the results are as expected (the good ones)