52832 antenna and matching network chips

[andy dong]

Hi all, Refer as the antenna whitepaper, The Zs = 50 Ohm pi network need to match. I saw a matched pass filter optimized for nrf52832 from Johanson (Part Number:2450FM07A0029).

Do We just put this BPF close to nRF52832 chips and chip antenna (2450AT18B100)? Any some other guidelines?

Thanks, Andy

[Jørn]

Hello andy

Page 2 of the 2450FM07A0029 product specification shows mounting instructions. You should keep the transmission line between the nRF52832 and the chip as short as possible.

Page 1 & 2 of the 2450AT18B100 product specification shows mounting instructions for the antenna, as well as matching. It is quite unlikely the antenna will naturally have 50 Ohm input impedance, so it will need matching. The product specification shows the typical mismatch without matching on page 2 with 2.760GHz lying closest to 50Ohm. The matching filter should be placed as close to the antenna as possible.

The transmission line between the Johanson matching chip, and the antenna matching network can be of some length if necessary as long as its properly designed to have a characteristic impedance of 50 Ohm. If it deviates from 50 Ohm the line will cause impedance transformation as a function of its length.

For additional design guidelines see this tutorial.

Best regards

Jørn Frøysa