5.7.6 Security Register Lock Bits (LB3, LB2, LB1)

The Security Register Lock bits (LB3, LB2, LB1) are One-Time Programmable (OTP) bits in Status Register 2 that provide write protection control for the Security Registers. The default value of LB3:LB1 is 0, which indicates that the Security Registers are unlocked. Each LB bit can be individually set to 1 using the Write Status Register instruction. Since these bits are OTP, once a bit is set to 1, the corresponding 256-byte Security Register becomes permanently read-only.