nRF5340 + nRF21540 connection

[Jose Pablo Castro Valverde]

Hi,

I have questions about the connections between the nRF5340 and the FEM nRF21540.

The nRF5340 has these components:

And the nRF21540 has this component:

I wonder if C3,C4,L1 and L2 are needed between these two IC.

Wouldn't be enough just used the C26?

I am using a single antenna.

The C28, C30 and L6 are needed to match the antenna impedance of 50Ohms, but I am not sure if it's actually needed to match impedance between ICs.

The same questions goes for the nRF52833 + nRF21540.

Any suggestions?

Thanks and best regards,

Jose Pablo Castro,

[Jose Pablo Castro Valverde]

Hi Ketiljo

I added this regulator to supply +3V0 voltage:

I got another question.

What about Push Button signal like these two:

Can both be connected to the VDD_nRF port of the nRF5340/nRF52833 or should I change it to +3V0 too?

I want to use the minimal amount of components, that's why I am using the configuration no. 1 for 52833

and configuration no. 4 for nRF5340:

I almost forget, I got three LEDs connected too:

Based on what have you told me I'm thinking I should connect these LEDs to +3V0 instead of VDD_nRF.

I am using 4 layer PCB and I make sure there's only ground below both nRF52833 and nRF5340.

Thanks and best regards,

Jose P. Castro

[ketiljo]

Since you now have an external 3 V regulator, the easiest is to use the nRF devices in normal voltage mode with both VDD and VDDH connected to +3V0. This will guarantee the same voltage on all logic levels.