Which is best RF design

[Dhruvit]

Hi, Everyone

I have space constraint in my round PCB for RF section where i have take referance from thingy91 board and choose the same components exept mcu is nrf5340 claa package.

here which is best I have no other option

[ketiljo]

Tha highly depends on the antenna. You need to follow the antenna manufacturers reference layout. Else, the design to the right would be the best.

[Dhruvit]

hi ketiljo 

thanks for reply

i also think right one is better 

here i have 1 question should i need to match impedance of 50 ohm in rf as i am using chip antenna as of now i have not find impedance matching in reference circuitry of nrf5340 .

for refrance i have taken same chip antenna used in thingy91 : 2450AT18D0100 where i could not find impedance matching in schematic so i have asked for it....

chip antenna : www.johansontechnology.com/.../2450AT18D0100.pdf

thabnks & regards 

[ketiljo]

Yes, you will need a matching circuit. Place a pi-filter befor the antenna, as indicated in the datasheet: