ABRIDGED DATA SHEET EVALUATION KIT AVAILABLE DS28EL25 DeepCover Secure Authenticator with 1-Wire SHA-256 with 4Kb User EEPROM General Description Features M DeepCover embedded security solutions cloak sensitive S Symmetric Key-Based Bidirectional Secure data under multiple layers of advanced physical security Authentication Model Based on SHA-256 to provide the industrys most secure key storage pos- S Dedicated Hardware-Accelerated SHA Engine for sible. The Deepcover Secure Authenticator (DS28EL25) Generating SHA-256 MACs combines crypto-strong, bidirectional, secure challenge- S Strong Authentication with a High Bit Count, User- and-response authentication functionality with an imple- Programmable Secret, and Input Challenge mentation based on the FIPS 180-3-specified Secure Hash Algorithm (SHA-256). A 4Kb user-programmable S 4096 Bits of User EEPROM Partitioned Into 16 Pages of 256 Bits EEPROM array provides nonvolatile storage of applica- tion data and additional protected memory holds a read- S User-Programmable and Irreversible EEPROM protected secret for SHA-256 operations and settings for Protection Modes Including Authentication, Write user memory control. Each device has its own guaranteed and Read Protect, and OTP/EPROM Emulation unique 64-bit ROM identification number (ROM ID) that is S Unique, Factory-Programmed 64-Bit Identification factory programmed into the chip. This unique ROM ID is Number used as a fundamental input parameter for cryptographic S Single-Contact 1-Wire Interface Communicates operations and also serves as an electronic serial num- with Host at Up to 76.9kbps ber within the application. A bidirectional security model enables two-way authentication between a host system S Operating Range: 1.8V 5%, -40C to +85C and slave-embedded DS28EL25. Slave-to-host authenti- S Low-Power 5A (typ) Standby cation is used by a host system to securely validate that S 8kV Human Body Model ESD Protection (typ) an attached or embedded DS28EL25 is authentic. Host- to-slave authentication is used to protect DS28EL25 user S 6-Pin TDFN Package memory from being modified by a nonauthentic host. The SHA-256 message authentication code (MAC), which the Typical Application Circuit DS28EL25 generates, is computed from data in the user memory, an on-chip secret, a host random challenge, 1.8V and the 64-bit ROM ID. The DS28EL25 communicates M R P over the single-contact 1-Wire bus at overdrive speed. R = 820 P V CC 2 The communication follows the 1-Wire protocol with the MAXIMUM I C BUS CAPACITANCE 400pF SDA 2 (I C PORT) ROM ID acting as node address in the case of a multiple- SCL DS24L65 device 1-Wire network. C 1-Wire LINE SLPZ IO Applications Authentication of Network-Attached Appliances DS28EL25 Printer Cartridge ID/Authentication Reference Design License Management System Intellectual Property Protection Ordering Information appears at end of data sheet. Sensor/Accessory Authentication and Calibration Secure Feature Setting for Configurable Systems 1-Wire and DeepCover are registered trademarks of Maxim Key Generation and Exchange for Cryptographic Integrated Products, Inc. Systems For related parts and recommended products to use with this part, refer to: www.maximintegrated.com/DS28EL25.related For pricing, delivery, and ordering information, please contact Maxim Direct at 219-0022 Rev 0 12/12 1-888-629-4642, or visit Maxim Integrateds website at www.maximintegrated.com.ABRIDGED DATA SHEET DS28EL25 DeepCover Secure Authenticator with 1-Wire SHA-256 with 4Kb User EEPROM ABSOLUTE MAXIMUM RATINGS IO Voltage Range to GND ...................................... -0.5V to 4.0V Storage Temperature Range ............................ -55NC to +125NC IO Sink Current ...................................................................20mA Lead Temperature (soldering, 10s) ................................+300NC Operating Temperature Range ......................... -40NC to +85NC Soldering Temperature (reflow) ......................................+260NC Junction Temperature .....................................................+150NC Stresses beyond those listed under Absolute Maximum Ratings may cause permanent damage to the device. These are stress ratings only, and functional opera- tion of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to absolute maximum rating conditions for extended periods may affect device reliability. ELECTRICAL CHARACTERISTICS (T = -40NC to +85NC, unless otherwise noted.) (Note 1) A PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS IO PIN: GENERAL DATA 1-Wire Pullup Voltage V (Note 2) 1.71 1.89 V PUP 1-Wire Pullup Resistance R V = 1.8V 5% (Note 3) 300 750 I PUP PUP Input Capacitance C (Notes 4, 5) 1500 pF IO Input Load Current I IO pin at V 5 19.5 FA L PUP High-to-Low Switching Threshold V (Notes 6, 7) 0.65 x V V TL PUP Input Low Voltage V (Notes 2, 8) 0.3 V IL Low-to-High Switching Threshold V (Notes 6, 9) 0.75 x V V TH PUP Switching Hysteresis V (Notes 6, 10) 0.3 V HY Output Low Voltage V I = 4mA (Note 11) 0.4 V OL OL Recovery Time t R = 750I (Notes 2, 12) 5 Fs REC PUP Time-Slot Duration t (Notes 2, 13) 13 Fs SLOT IO PIN: 1-Wire RESET, PRESENCE-DETECT CYCLE Reset Low Time t (Note 2) 48 80 Fs RSTL Reset High Time t (Note 14) 48 Fs RSTH Presence-Detect Sample Time t (Notes 2, 15) 8 10 Fs MSP IO PIN: 1-Wire WRITE Write-Zero Low Time t (Notes 2, 16) 8 16 Fs W0L Write-One Low Time t (Notes 2, 16) 1 2 Fs W1L IO PIN: 1-Wire READ Read Low Time t (Notes 2, 17) 1 Fs 2 - d RL Read Sample Time t (Notes 2, 17) 2 Fs t + d MSR RL EEPROM Programming Current I V = 1.89V (Notes 5, 18) 1 mA PROG PUP Programming Time for a 32-Bit t (Note 19) 10 ms PRD Segment or Page Protection Programming Time for the Secret t Refer to the full data sheet. ms PRS Write/Erase Cycling Endurance N T = +85NC (Notes 21, 22) 100k CY A Data Retention t T = +85NC (Notes 23, 24, 25) 10 Years DR A Maxim Integrated 2