FEM Control with nrf5340, Current Consumption too High.

RE: FEM Control with nrf5340, Current Consumption too High.

ovrebekk — Sat, 16 Sep 2023 08:05:27 GMT

Hi Devin

You welcome, great to hear you found the solution 🙂

I will close the case then.

Best regards
Torbjørn

RE: FEM Control with nrf5340, Current Consumption too High.

Devin M — Fri, 15 Sep 2023 00:55:01 GMT

It was due to the spi-if not being included in the nrf_fem section of the overlay node. I had to assign my spi module, with the pins listed in the lzc_fem spi module, with a name and assign that to spi-if.

Thanks for your help!

RE: FEM Control with nrf5340, Current Consumption too High.

ovrebekk — Thu, 14 Sep 2023 10:38:50 GMT

Hi Devin

[quote user="Devin M"]Thinking it may be due to the exemption of the spi-if portion of the nrf21540_fem portion in the overlay currently. But will need to implement the SPI module passed through in nrf21540_lcz_fem in order to be used for spi-if.[/quote]

You mean to say you are not using the official overlays provided by Laird?

I will try to reach out to Laird as well, to hear if they have tested the sleep current of the module.

What kind of firmware are you running on the board? Is it a standard Bluetooth application running the SoftDevice controller?

Best regards
Torbjørn

RE: FEM Control with nrf5340, Current Consumption too High.

Devin M — Wed, 13 Sep 2023 14:01:04 GMT

Thank you! Yes, that does complicate it that the FEM control pins are not accessible for probing due to the module. Thinking it may be due to the exemption of the spi-if portion of the nrf21540_fem portion in the overlay currently. But will need to implement the SPI module passed through in nrf21540_lcz_fem in order to be used for spi-if.

RE: FEM Control with nrf5340, Current Consumption too High.

ovrebekk — Wed, 13 Sep 2023 13:30:31 GMT

Hi Devin

I asked around internally to see if this could be a known issue, but it doesn't seem so.

I assume it would be difficult to get access to the FEM control pins on your module so you could check the state of these pins in sleep?

I will do some measurements using an nRF5340DK and the nRF21540EK trying to reproduce the problem here, and I will do my best to get back to you with an update in a day or two.

Best regards
Torbjørn