Protect Your Design Using Crypto-Strong Authentication Secured with a Physically Unclonable Function
The DS28C39 is an ECDSA public-key-based bidirectional secure authenticator that incorporates Maxim’s patented ChipDNA™ feature, a physically unclonable function (PUF) to provide a cost-effective solution with the ultimate protection against security attacks.
Using the random variation of semiconductor device characteristics that naturally occur during wafer fabrication, the ChipDNA circuit generates a unique output value that is repeatable over time, temperature, and operating voltage. Attempts to probe or observe ChipDNA operation modifies the underlying circuit characteristics, preventing discovery of the unique value used by the chip cryptographic functions. The DS28C39 utilizes the ChipDNA output as key content to cryptographically secure all device stored data and as the private key for the ECDSA signing operation. With ChipDNA capability, the device provides a core set of cryptographic tools derived from integrated blocks including an asymmetric (ECC-P256) hardware engine, a FIPS/NIST-compliant true random number generator (TRNG), 2Kb of secured EEPROM, a decrement-only counter and a unique 64-bit ROM identification number (ROM ID). The ECC public/ private key capabilities operate from the NIST-defined P-256 curve to provide a FIPS 186-compliant ECDSA signature generation function. The unique ROM ID is used as a fundamental input parameter for cryptographic operations and serves as an electronic serial number within the application. Lastly, the DS28C39 supports I2C communication at the 100kHz standard mode.