I have to develop a project with a CC1200. I need to customize it and i would like to know the measurement condition of the PA and RX impedance. Reading the DS i found the parameters of the single ended PA and the Differential RX.
On your application note, i see that the PA is fed externally. Is the impedance at 868MHz of 35+j35 with the 10nH 15pF elements? Otherwise would it be enough an RF choke and a PI matching 60 to 50 ohm?
See attached Fig 1
About the RX line i see a weird configuration of the DIFF to SE transformer.. is the L191 (15nH) to give a ground path to both side of the LNA? In that case the impedance will be slightly different..
I did some simulation, and i found what you can see in Fig 2. (Using a 2 ports model)
Waiting for your suggestion...
Fig1 Fig 2
Thank you for your help,