nrf21540 rf switch isolation

[Gabriel Chouinard]

I'm currently working with a BL5340PA module with the external antenna connector. we were wondering what was the RF switch isolation between the two antenna outputs. In other words, when we select ANT1, how much leakage is there in ANT2.

[Elfving]

Hi Gabriel, 

I think this depends on the BL5340PA HW. We've only created the nRF, not the modules, so I think this might be a question that is better suited to be asked Ezurio. Let me know if they disagree, and I'll try to look into it.

Regards,

Elfving

[Gabriel Chouinard]

unless I'm mistaken, the rf switch is part of the nrf21540. The nrf21540 it self should have a specification regarding the isolation of its antenna outputs. 

[Elfving]

You are right. I've forwarded the question to the relevant R&D team, I'll let you know once I hear from them. Is this request urgent for you?

Regards,

Elfving

[Gabriel Chouinard]

we are currently investigating a solution with an external antenna with a band pass filter to attenuate the 3rd harmonic of the FEM. We already measured a difference of about 10 dB when switching antenna and we only wanted to validate our measurements. So no it is not urgent.  

[Elfving]

It should be about ~37dB. Is that precise enough for you?

Regards,

Elfving

[Gabriel Chouinard]

yes thank you!