TX pin not set on transmission using FEM

[Marius Waage Aabel]

Hi,

We use the SKY66112 FEM in front of nRF5340. The FEM is configured in the DTS file. On our ordinary firmware, the TX pin is set and reset automatically. I can see the TX pulse on the scope on transmission.

We are also using the Radio Test project for certification purposes.We have added the Radio Test as an app in the main project, so that we use the same board files as in the main firmware. Radio Test works well without FEM enabled (by manually setting it in bypass mode).

When FEM is enabled, however, it does not work. The TX pin is not set before transmission.

When looking on the source, the FEM is implemented in the Radio Test project. Is the TX pin not being controlled automatically a bug in the Radio Test?

Marius

[Priyanka]

Hi Marius,

Have you referred to the documentation on Skyworks FEM ? Also, what version of nRF Connect SDK are you using? Are you referring to the TX pin on the FEM? Is the TX pin enabled? i.e. is it set to later or not set at all? Have you checked with the datasheet whether it is active high or low?

Best Regards,

Priyanka