1280-Bit EEPROM with SHA-1 Authentication

The DS2704 provides 1280 bits of EEPROM data storage and a Secure Hash Algorithm (SHA) engine. The Dallas 1-Wire® interface enables serial communication on a single battery contact and the 64-bit unique serial number allows multidrop networking and identification of individual devices.

The 1280-bit memory is organized as 5 pages of 32 bytes each and supports storage of battery cell characteristics, charging voltage, current, and temperature parameters, as well as battery pack manufacturing data. The EEPROM pages are in circuit rewritable and can be individually locked to write protect data.

The DS2704 employs the Secure Hash Algorithm (SHA-1) specified in the Federal Information publication 180-1 and 180-2, and ISO/IEC 10118-3. SHA-1 provides a robust cryptographic solution to ensure battery packs or other peripherals have been manufactured by authorized sources. The DS2704 processes a host transmitted challenge and the 64- bit secret key stored on chip to produce a 160-bit response for transmission back to the host. The secret key is never transmitted between the battery and the host.

Applications

* 2.5G/3G Wireless Handsets * Digital Still and Video Cameras * Handheld or Notebook Computers and Terminals * PDAs

* Secure Challenge and Response Authentication Using the SHA-1 Algorithm

* Five Lockable 32-Byte Pages of EEPROM

* Dallas 1-Wire Interface with Standard and Overdrive Communications Speeds

* Unique 64-Bit Serial Number

* Compatible with DS2502 Memory Map and Read Function Command

* Operates with VDD as Low as 2.5V

* Tiny Chip-Scale UCSP and 3mm x 3mm TDFN Packaging (Pb-Free)