Is NFC.TAGHEADER0 to NFC.TAGHEADER3 assured to be unique for each produced nRF?

[VictorFV]

Hi,

I'm building a solution in which I would like to rely on the uniqueness of the default UID read when doing NFC tag emulation. I would like to know if the default UIDs are actually assured to be unique by Nordic, or just random (and given the address space unlikely enough to have two chips with the same UID).

Also, if they are unique, are they unique only when using the 10-byte version, or the smaller 4 or 7-byte versions are unique on their own as well?

I saw some other posts in which it was implied that they are likely unique, but I couldn't find a proper confirmation.

Thank you!

[Einar Thorsrud]

Hi,

The unique identifiers in the TAGHEADER registers are puplated with random numbers in production (though the nubmers are screened for invalid values per the NFC forum specification). They are not guaranteed to be unique.