nRF54L15 Design Verification

[PoojaK]

NORDIC-NRF-V1 (1).brdGERBER-SPJ_NORDIC_NRF-V1.zipNORDIC-NRF-V1 (1).schNORDIC-NRF-V1 SCHEMATIC.pdf I really need to verify this design for nrf54L15 SoC. If someone can go through it and confirm if it is okay or I need to make any changes ? I had made nRF52832 board but it did not work. So I want this design to be thoroughly verified, especially the antenna section for RF application. Awaiting replies as this has become a major bottleneck now for my projects.

[Szabolcs]

Hi,

This looks better.

On the C18 ground pin, place a filled triangle region on the vias and the pad, like in the picture:

With these thin traces, you are introducing parasitic inductances between the vias, which is not good.

You can also keep the ground in the inner layers below the matching, a closer ground plane reduces the harmonic emissions. Just place a cutout around the triangle of the 3 vias.

[PoojaK]

Thank you for your prompt reply. I will make this change and upload the design. Anything else that I need to change in the schematic, component values, placement or routing. I am attaching the final schematic PDF here.NORDIC-NRF-V1.pdf

[Szabolcs]

Any generic substrate will do fine. Our recommendation is to have a prepreg thickness less than 100um (between top and first inner layer).

[PoojaK]

I have got the PCB assembled now. How do i flash the program in it using VS Code and which SoC i should select

[Szabolcs]

Hi,

Please see Creating an application in the Nordic documentation page, and also the Developing with custom boards section. Your target SoC is nrf54l15.

If you open the nRF Connect extension in VS Code, you'll see the option "Flash". You'll need to have a debugger connected to the SWD pins on your board, this could be a SEGGER J-Link, a Nordic DevKit, etc.

Is there a specific step you are stuck on?

[PoojaK]

The program is getting dumped correctly in the custom PCB. The issue is with the RF section. None of the wireless protocols are working. There is some major issue with the antenna section and impedance matching section. I will share the gerber and final design files. Also please can you verify if the components in antenna section are correctly tracked, and if we can use components of 0603 package and place them at a reasonable distance from each other. I was very disappointed that even after taking care in the placement and routing, the RF part is not working.8322.GERBER-SPJ_NORDIC_NRF-V1.zip0841.NORDIC-NRF-V1.sch2068.NORDIC-NRF-V1.brd

[Szabolcs]

I see, so that the issue is with the wireless part of the software. What exactly are you experiencing, do you not see any RF output from the PCB?

It is very unlikely that the problem is with the hardware. Your gerber files look fine, and even if the matching network was completely wrong, you should see some signs of wireless activity (e.g. phone picking up BLE Advertising within a meter, spectrum analyzer showing a weak signal, etc.). So I do believe that this is a firmware issue which can be solved.

Unfortunately, it is not possible to use 0603 components in the RF section, as these have completely different characteristics than the 0201 components. The matching network is very sensitive to the layout and component values due to the high frequencies.

Please open another ticket where you describe how you created your firmware project, what example you used and what modifications you made. One of my coworkers specialized in firmware development will support you with debugging your project.

[PoojaK]

Okay. Thank  you. I will do s