Power Profiler Kit II digital channel data readings

[Peter Murphy]

Dear Nordic,

We are performing current measurements on a nRF-9151 DK using the Power Profiler Kit II. The attached picture shows the 9151 and PPK-II connected. Notice that we don't have anything connected to the Logic Ports of the PPK-II. 

In the first set of tests we used the Power Profiler v4.3.1 application which is part of the nRF Connect for Desktop application. Things worked well. The current measurements make sense and the digital channel plot shows that all 8 digital channels are low (see the screenshot below). Since we don't have anything connected to the Logic Ports this is what we expect.

For our next phase of testing we developed some python code to read the data from the PPK-II over the serial port. In this case the current data is what we expect. However, the logic level for Digital Channel 1 is alway high while the other 7 channels are low. 

Can you offer some help in understanding why Digital Channel is 1? The Logic Ports still have nothing connected to them.

Regards,

Peter

[Simonr]

Hi

To use the logic ports, connect the following, and the digital signal should be visible on the logic port Dx pins:

• DUT's VCC to the PPK2 logic port VCC pin
• DUT's GND to the PPK2 logic port GND pin
• DUT's digital signal to any logic port Dx pin

How are the digital channels connected exactly on your end? In general, issues with digital channels in the past has been due to incorrect connections of the digital channels.

Best regards,

Simon

[Peter Murphy]

Hi Simon,

I'm using the PPK2 with an nRF9151 DK. What pin on the 9151 DK can I use as the VCC which connects to the PPK2 logic port VCC pin. Also, what pin on the 9151 DK can I use as the GND which connects to the PPK2 logic port GND pin. Last question, is there a digital signal on the 9151 DK which is always high which I can connect to the logic port Dx on the PPK2?

Thanks.

Peter