Preliminary DTM power assessment using the DK board

[sean]

Hi，

    Hello, I frequently need to perform BLE DTM testing, but there is only one CWM500 instrument available, and I have to queue up and wait for it every time I run tests. Sometimes the PCB boards are very small, with 0201 components that are also tiny. Poor soldering may require rework, which wastes a lot of time. My current idea is: use the IPEX connector on the nRF54L15-DK to input the signal from the device under test, and have the nRF54L15-DK output approximate power values via log to help me determine whether the soldering is good. I've looked at the existing examples and none of them have this feature. What is the simplest way to implement this?

[Håkon Alseth]

Hi,

 

Do I understand the scenario correct when you want to test DTM with two nRF boards?

Ie. a nRF as the tester, and a nRF as the DUT (device under test)?

 

If yes, then this is possible, but there will be restrictions as compared to running said test with a R&S CMW500 (or any other dedicated bluetooth tester).

There is an older application note nAN-34: https://docs.nordicsemi.com/bundle/nan_34/resource/nan_34.pdf

Which describes the theoretical setup, with 2 nRF devices connected to a PC, controlling both.

 What I would recommend in your case is to use an RF attenuator between the nRF-to-nRF, and see how many packets the DUT is able to send/receive.

 

Kind regards,

Håkon

[sean]

Hi，

    Thank you for your reply. I have a look. The nRF51 chip in it is very old. I want to get the approximate signal strength with the new nRF54L chip. What is the approximate direction for guidance? I'll try it.

[Håkon Alseth]

Hi,

 

The application note is about using DTM for production testing, and is not specific to the nRF51-series device.

sean said:

What is the approximate direction for guidance? I'll try it.

We do not have a specific setup for you in this case, but it is possible to use the "Direct test mode" PC application with two nRF devices.

Where you can setup one as a transmitter, and one as a receiver for instance.

 

If you search on google, there is probably someone that made a simpler python script or similar for DTM, so that you can potentially automate the process.

  

Kind regards,

Håkon