I use the nRF52840-QIAA and in the datasheet are 2 different reference designs for the ANT pin. 3 or 4 component matching and filter network. When I calculate the impedance of the 2 filters I got 2 complete different impedance.
Z = 112Ω - j15Ω
Z = 65.8Ω - j30.5Ω
I found here the impedance of 111.8 - 32.9j which would match with the 3 component solution. But I can't explain the impedance for the 4 component solution. Could you please explain why there is such a big difference in this 2 different reference designs.
Could you please provide the impedance of the ANT pin. If the output impedance is dependent from the output power than I am interested in the values of 0 and 8 dBm.
As my antenna has not 50 Ohm I would add only one matching / filtering network from ANT pin to antenna fed point.
