Maxim Integrated MAX32600, Руководство пользователя

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MAX32600 User’s Guide Trust Protection Unit (TPU)
11 Trust Protection Unit (TPU)
Trust Protection Unit (TPU)
The TPU on the MAX32600 provides support for cryptographic data security and automatic response to external attacks against the device. Although the MAA and
the AES engine are covered in separate sections, these are also considered to be part of the TPU as well.
Features included in the TPU:
• Physically Unclonable Feature (PUF), a block which allows a unique random number sequence to be generated, with each physical MAX32600 part producing
a different number sequence. Although the PUF output sequence produced by a particular
MAX32600
will always be repeatable by that physical device, the
sequence produced by a particular
MAX32600
cannot be predicted in advance since it depends on manufacturing process variations.
• Pseudo-random number generator, allowing random numbers to be generated by combining a user-selected entropy source with internal clock-based entropy
and other sources of hardware random noise.
• A dynamic Tamper Sensor (TSR) generates a randomized signal sequence that can be used to construct a physical enclosure shield that cannot be disrupted
by an external attacker. If the signal path in the enclosure shield is broken, the tamper sensor triggers, causing an automatic clear of the "key of keys" registers
inside the TPU and also triggering an automatic erasure of all AES memory.
11.1 AES Cryptographic Engine
The MAX32600 includes an AES cryptographic engine which can perform AES encryption/decryption operations. Supported key lengths are 128-bits, 192-bits, and
256-bits.
11.1.1 Registers (AES)
11.1.1.1 Module AES Registers
Address Register
32b
Word Len Description
0x40011400 AES_CTRL 1 AES Control and Status
0x40011408 AES_ERASE_ALL 1 Write to Trigger AES Memory Erase
0x4010A000 AES_MEM_INP0 1 AES Input 0 (least significant 32 bits)
0x4010A004 AES_MEM_INP1 1 AES Input 1
Rev.1.3 April 2015 Maxim Integrated Page 608