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CR95HF VPS_TX current vs matching impedance

Question asked by Gutierrez.David on Nov 17, 2016
Latest reply on Dec 8, 2016 by Peter Boringer

I would like to design a system with a controlled consumption in the RF side of the CR95HF. I have read different application notes and made some calculations using your Excel matching file, but still have some doubts.

1. The current can be calculated as I_tx = (VPS_TX) / (Zout + Zmatching)?
2. The datasheet says its value is between 70mA and 100mA for 3V output voltage operation. It means an impedance between 30 and 42 ohms, but the recommended is 27. Where does this 100mA values come from?
3. What is the maximum current I can drive to the antenna?
4. Should I set the operating voltage (3V/5V) via register or it is automatically set with the voltage level at VPS_TX?

Thank you