The OTP zone of 64 bytes (512 bits) is part of the EEPROM array and can be used for read-only storage. It is organized as two blocks of 32 bytes each. For the ATECC608A-TNGLoRaWAN, the OTP zone is shipped pre-locked and contains the following information:
6A 73 4D 75 37 69 59 4F 00 00 00 00 00 00 00 00
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
30 39 71 4A 4E 78 49 33 00 00 00 00 00 00 00 00
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
The data byte values written into the OTP zone are always available for reading using either 4 or 32-byte reads but can never be modified.