EEPW论坛

【应用手册】AN 589: Using the Design Security Feature in Cyclone III LS Devices
This application note describes the design security feature in Cyclone® III LS devices.
The design security feature is able to decrypt a configuration bitstream using an
industry standard 256-bit advanced encryption standard (AES) key and AES
encryption algorithm to protect your designs from the following unauthorized
activities:
■ Copying
■ Reverse engineering
■ Tampering
The following design features make the solution secure:
■ Cyclone III LS devices do not support configuration file read back. This prevents
attempts to read back the configuration file after it is decrypted.
■ Two user-defined 256-bit sequences are required to generate the 256-bit AES key.
■ The volatile 256-bit AES key is stored in the Cyclone III LS device and cleared
when the external battery is removed.
■ Depending on the security mode, you can configure the Cyclone III LS device
using a configuration file that is encrypted with the same key, or configure with a
normal configuration file for board level testing.
AN589.pdf