Hi,
Thank you for contacting Infineon Technologies.
If the user wants to protect some of the sectors from program or erase operations where once the data is programmed it does not require to be updated/modified then we provide the option through Highest sector protection or Lowest address sector protection.
User can choose which sector to be protected Highest or lowest depending on your choice and order part umber accordingly.
The highest address sector protected means when you drive WP (Write Protect Signal) low by default the last sector outermost sector remains protected/locked and the lowest address sector protected means when you drive WP low by default first or initial sector is protected. either the highest or lowest sector is locked (device-specific). You can select device according to ordering part number from data sheet considering Model Number.
Hope it clarifies your query.
Thanks and Regards,
Yuvraj
