If I do not plan on using the energy harvested from the the NFC feilds, but want to be notified when a field is present using the FD pin, do I need capacitors on Vout ? The I2C bus will be powered by the host microcontroller.
The main purpose of the capacitance of Vout pin is to decouple, which prevents the parasitic oscillation caused by the positive feedback path formed by the power supply.
Since you want to use FD function, and the Vout pin must have voltage output at this time, my opinion is to add this capacitor.
Have a nice day!