nRF52840-CKAA ANT Port Impedance

Question

Is the nRF52840-CKAA port impedance for the various transmit power settings (or at least for 8dBm) available? 
 Alternatively, is the expected port impedance, when viewed from the antenna side into the end of the recommended matching network, roughly 50 ohms (see "Circuit configuration no. 1 for CKAA WLCSP" in nRF52840_PS_v1.7)?

mathiaso · Accepted Answer

johnny89 said: If the output port impedance does change with transmit power, I assume the only "easy" option I have is to set the nRF to transmit a CW tone with my intended transmit power (8dBm) and measure it with something that has a known 50-ohm load (like a spectrum analyzer and some attenuators) to confirm that I get 8dBm out. If not, I experimentally tweak the matching circuit until I do. 
 Yes, that is the way to do it. Look at how the output power of the fundamental frequency and the harmonic frequency change depending on the matching network. 
 mathiaso said: You can upload your schematic and layout here for me to look at the design, but then I should make the ticket private first. 
 This is still an option if you want to. We also offer a tuning service, free of charge.

nRF52840-CKAA ANT Port Impedance

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