MAXIM DS28C22Q+T

DeepCoverM embedded security solutions cloak sensi­ tive data under multiple layers of advanced physical security to provide the most secure key storage possible. The DeepCover Secure Memory (DS28C22) combines crypto-strong, bidirectional, secure challenge-andresponse authentication and small message encryption functionality with an implementation based on the FIPS 180-specified Secure Hash Algorithm (SHA-256). A 3Kb user-programmable EEPROM array provides nonvola­ tile storage for application data and additional protected memory holds a read-protected secret for SHA-256 oper­ ations and settings for user memory control. Each device has its own guaranteed unique and unalterable 64-bit ROM identification number (ROM ID) that is factory pro­ grammed into the chip. This unique ROM ID is used as a fundamental input parameter for cryptographic operations and also serves as an electronic serial number within the application. A bidirectional security model enables twoway authentication and encryption between a host system and slave-embedded DS28C22. Slave-to-host authenti­ cation is used by a host system to securely validate that an attached or embedded DS28C22 is authentic. Hostto-slave authentication is used to protect DS28C22 user memory from being modified by a nonauthentic host. The SHA-256 message authentication code (MAC), which the DS28C22 generates, is computed from data in the user memory, an on-chip secret, a host random challenge, and the 64-bit ROM ID. The device also facilitates encrypted read and write between host and slave using a one time pad computed by the SHA-256 engine. When not in use, the DS28C22 can be put in sleep mode where power consumption is minimal.

• Symmetric Key-Based Bidirectional Secure Authentication and Encryption Model Based on SHA-256
• Dedicated Hardware-Accelerated SHA Engine for Generating SHA-256 MACs
• Strong Authentication with a 256-Bit, UserProgrammable Secret, and Input Challenge
• 3072 Bits of User EEPROM Partitioned Into 12 Pages of 256 Bits
• User-Programmable and Irreversible EEPROM Protection Modes Including Authentication, Write and Read Protect, Encryption, and OTP/EPROM Emulation
• Supports 100kHz and 400kHz I2C Communication Speeds
• Supports Power-Saving Sleep Mode at 0.5μA (typ)
• Operating Range: 3.3V ±10%, -40°C to +85°C
• 8-Pin TDFN Package

• Authentication of Network-Attached Appliances
• System Intellectual Property Protection
• Secure Feature Setting for Configurable Systems
• Key Generation and Secure Exchange for Crypto graphic Systems