2.3 ATECC608B-TFLXTLS EEPROM One Time Programmable (OTP) Zone

The OTP zone of 64 bytes (512 bits) is part of the EEPROM array and is used for read-only storage. It is organized as two blocks of 32 bytes each. For the ATECC608B-TFLXTLS, the OTP zone is shipped pre-locked and contains the following information:

I2C device version

    77 64 4E 78 41 6A 61 65 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

SWI device version

    42 57 75 7A 4D 6F 41 61 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.
Notice: The bytes in the OTP zone may change over time. These values should not be used in any cryptographic calculations.