Problems with Power Profiler Kit II

RE: Problems with Power Profiler Kit II

Øyvind — Thu, 11 Jul 2024 11:21:13 GMT

Hello,

Can you please provide more information on what you are running on your board?

The nRF9161DK documentation provides more information on the power supply.

Kind regards,
Øyvind

RE: Problems with Power Profiler Kit II

PaKa — Thu, 11 Jul 2024 06:14:58 GMT

My area is the PPK2 so you will need to check the nRF9161 DK documentation for that, or measure the voltage.

RE: Problems with Power Profiler Kit II

Pietro Marrone — Wed, 10 Jul 2024 15:36:22 GMT

Thanks a lot for the suggestion. What about the voltage ‘V’ that powers the device, considering it is connected via a USB cable to my laptop? Is it 3.3V or 5V?

RE: Problems with Power Profiler Kit II

PaKa — Wed, 10 Jul 2024 10:38:34 GMT

The suggestion is to break down the problem inot smaller pieces. Know you are getting numbers that you don't know if are correct or not. It could be a HW issue or it could be a SW issue. If you test with a FW with known power consumption then you can see if the HW is working as it should. If that is the case, then you can trust the numbers and if the current is not what you expect, then you know you have a FW issue on your board.

RE: Problems with Power Profiler Kit II

Pietro Marrone — Wed, 10 Jul 2024 10:05:22 GMT

I actually didn't understand so well the second part. My goal is to verify the power saving capabilities of the devices when they are used with the DECT NR+ standard, so I wanted to measure the power consumed during an established communication between 2 devices using DECT NR+.

RE: Problems with Power Profiler Kit II

Pietro Marrone — Wed, 10 Jul 2024 10:02:09 GMT

this is my setup

RE: Problems with Power Profiler Kit II

PaKa — Wed, 10 Jul 2024 07:04:31 GMT

Can you provide a picture of your actual setup as the one you sent can't be used to verify it is correct?

For current measurement the recommendation is to take a sample with known power consumption and test first to validate your setup. Best way is one that doesn't use the radio as if you can't connect then that will dominate the power consumption.

RE: Problems with Power Profiler Kit II

Pietro Marrone — Tue, 09 Jul 2024 15:13:58 GMT

I also have another question: in order to calculate the power dissipation based on the device’s current consumption, I need to use the formula P = V*i, where ‘i’ represents the average current drawn by the device. Could you please clarify what is the value of the voltage ‘V’ that powers the device, considering it is connected via a USB cable to my laptop?

Your assistance on this matter would be greatly appreciated.

RE: Problems with Power Profiler Kit II

Pietro Marrone — Tue, 09 Jul 2024 14:48:17 GMT

Thank you for your detailed message. Luckily, I noticed myself (before using the device) that the black wire was incorrectly connected to a non-connected pin instead of GND, as specified in the user guide. I just uploaded an incorrect image taken before the use of the devices. Regarding the brown and red wire connections, I confirm that the brown wire was correctly connected to VDD_5V and the red wire to VDD_nRF, as you indicated.

However, I still had encountered some issues and would like to know if there are specific actions to take when finishing the use of both devices to prevent damage. For instance, is it necessary to power off the DK before removing the PPK2?

Additionally, I have doubts about the current consumption value readout, which fluctuates between 31 and 32 mA. Does this value solely represent the power consumption of the nRF9161 DK, or could there potentially be an influence from the Power Profiler device itself on the power consumption of the nRF9161 DK?

RE: Problems with Power Profiler Kit II

PaKa — Tue, 09 Jul 2024 11:00:55 GMT

So you have connected the PPK2 incorrectly it seems.

If you check the marking then the black wire is ground and MUST be connected to GND. According to the nRF9161 DK user guide you have connected this to a non-connected pin.

The brown wire is the power input for the amperemeter so should go to the power source (VDD_5V), seems you have connected it to the power drain (VDD_nRF) and thus the red wire that is the power output is connected to the power source.

The PPK2 can only measure current in one direction so this will not work, hopefully it is not damaged.

Double check the PPK2 user guide as well as the nRF9161 DK user guide to make sure you hook it up the correct way. Remember that if you remove the PPK then you will need to re-insert the jumper.