DS2432

1Kb Protected 1-Wire EEPROM with SHA-1 Engine


Description

The DS2432 combines 1024 bits of EEPROM, a 64-bit secret, an 8-byte register/control page with up to five user read/write bytes, a 512-bit SHA-1 engine, and a fully-featured 1-Wire interface in a single chip. Each DS2432 has its own 64-bit ROM registration number that is factory lasered into the chip to provide a guaranteed unique identity for absolute traceability. Data is transferred serially via the 1-Wire protocol, which requires only a single data lead and a ground return. The DS2432 has an additional memory area called the scratchpad that acts as a buffer when writing to the main memory, the register page or when installing a new secret. Data is first written to the scratchpad from where it can be read back. After the data has been verified, a copy scratchpad command will transfer the data to its final memory location, provided that the DS2432 receives a matching 160-Bit MAC. The computation of the MAC involves the secret and additional data stored in the DS2432 including the device's registration number. Only a new secret can be loaded without providing a MAC. The SHA-1 engine can also be activated to compute 160-bit message authentication codes (MAC) when reading a memory page or to compute a new secret, instead of loading it. Applications of the DS2432 include intellectual property security, after-market management of consumables, and tamper-proof data carriers.

Key Features

  • 1128 Bits of 5V EEPROM Memory Partitioned Into Four Pages of 256 Bits, a 64-Bit Write-Only Secret, and Up to Five General-Purpose Read/Write Registers
  • On-Chip 512-Bit ISO/IEC 10118-3 SHA-1 Engine to Compute 160-Bit Message Authentication Codes (MACs) and to Generate Secrets
  • Write Access Requires Knowledge of the Secret and the Capability of Computing and Transmitting a 160-Bit MAC as Authorization
  • Secret and Data Memory Can Be Write Protected (All or Page 0 Only) or Put in EPROM-Emulation Mode ("Write to 0", Page 1)
  • Unique, Factory-Lasered and Tested 64-Bit Registration Number Assures Absolute Traceability Because No Two Parts Are Alike
  • Built-In Multidrop Controller Ensures Compatibility with Other 1-Wire® Net Products
  • Reduces Control, Address, Data, and Power to a Single Data Pin
  • Directly Connects to a Single Port Pin of a Microprocessor and Communicates at Up to 15.3kbps
  • Overdrive Mode Boosts Communication Speed to 90.9kbps
  • Low-Cost 6-Lead TSOC Surface-Mount Package or Solder-Bumped UCSP™ Package
  • Reads and Writes Over a Wide Voltage Range of 2.8V to 5.25V from -40°C to +85°C

Applications/Uses

  • Device Authentication
  • IEEE 1451.4 Sensor TEDS
  • Ink/Toner Cartridges
  • Medical Sensors
  • PCB Identification
  • Self-Configuration of Central Office Switches, Wireless Base Stations, PBXs, or other Modular-Based Rack Systems

Technical Documents

App Note 5507 Understanding the DS1WM Synthesizable 1-Wire Bus Master
App Note 5485 Understanding the DSSHA1 Synthesizable SHA-1 Coprocessor
App Note 5403 How to Build a 1-Wire® Evaluation Kit
App Note 4717 Injection Molding an IC into a Connector or Consumable Item
Reference Schematic 4477 Reference Design of a 1-Wire® Bidirectional Voltage-Level Translator for 1.8V to 5V
App Note 4427 Demonstrating Green Technology with Apples, Oranges, Lemons, and Limes
App Note 4255 How to Power the Extended Features of 1-Wire® Devices
App Note 4132 Attachment Methods for the Electro-Mechanical 1-Wire Contact Package
App Note 4002 Understanding Flip-Chip and Chip-Scale Package Technologies and Their Applications
App Note 3826 Xilinx® FPGA IFF Copy Protection with 1-Wire® SHA-1 Secure Memories
App Note 3522 White Paper 9: Are SHA-1 Devices Still Secure Enough?
Tutorial 3438 Serial Digital Data Networks
App Note 3377 Maxim Wafer-Level Package Assembly Guide
App Note 1820 White Paper 1: SHA Devices Used in Small Cash Systems
Tutorial 1201 White Paper 8: 1-Wire® SHA-1 Overview
App Note 1100 White Paper 5: Using 1-Wire APIs for Data Sheet Commands
App Note 1099 White Paper 4: Glossary of 1-Wire SHA-1 Terms
App Note 1098 White Paper 3: Why are 1-Wire SHA-1 Devices Secure?
App Note 1097 White Paper 2: Using the 1-Wire® Public Domain Kit
Reference Schematic 244 Advanced 1-Wire Network Driver
App Note 192 Using the DS2480B Serial 1-Wire® Line Driver
App Note 190 Challenge and Response with 1-Wire® SHA Devices
App Note 187 1-Wire Search Algorithm
App Note 178 Printed Circuit Board Identification Using 1-Wire® Products
App Note 155 1-Wire Software Resource Guide Device Description
App Note 154 Passwords in SHA Authentication
App Note 151 Maxim Digital Monetary Certificates
Tutorial 148 Guidelines for Reliable Long Line 1-Wire Networks
App Note 126 1-Wire Communication Through Software
App Note 74 Reading and Writing 1-Wire® Devices Through Serial Interfaces
App Note 27 Understanding and Using Cyclic Redundancy Checks with Maxim 1-Wire and iButton Products

Quality and Environmental Data

Product Reliability Reports: DS2432.pdf 
Lead-Free Package Tin (Sn) Whisker Reports

Additional Resources

Sensor Calibration

Related Resources

Type ID PDF Title
App Note 5507 Understanding the DS1WM Synthesizable 1-Wire Bus Master
App Note 5485 Understanding the DSSHA1 Synthesizable SHA-1 Coprocessor
App Note 5403 How to Build a 1-Wire® Evaluation Kit
App Note 4717 Injection Molding an IC into a Connector or Consumable Item
Reference Schematic 4477 Reference Design of a 1-Wire® Bidirectional Voltage-Level Translator for 1.8V to 5V
App Note 4427 Demonstrating Green Technology with Apples, Oranges, Lemons, and Limes
App Note 4255 How to Power the Extended Features of 1-Wire® Devices
App Note 4132 Attachment Methods for the Electro-Mechanical 1-Wire Contact Package
App Note 4002 Understanding Flip-Chip and Chip-Scale Package Technologies and Their Applications
App Note 3826 Xilinx® FPGA IFF Copy Protection with 1-Wire® SHA-1 Secure Memories
App Note 3522 White Paper 9: Are SHA-1 Devices Still Secure Enough?
Tutorial 3438 Serial Digital Data Networks
App Note 3377 Maxim Wafer-Level Package Assembly Guide
App Note 1820 White Paper 1: SHA Devices Used in Small Cash Systems
Tutorial 1201 White Paper 8: 1-Wire® SHA-1 Overview
App Note 1100 White Paper 5: Using 1-Wire APIs for Data Sheet Commands
App Note 1099 White Paper 4: Glossary of 1-Wire SHA-1 Terms
App Note 1098 White Paper 3: Why are 1-Wire SHA-1 Devices Secure?
App Note 1097 White Paper 2: Using the 1-Wire® Public Domain Kit
Reference Schematic 244 Advanced 1-Wire Network Driver
App Note 192 Using the DS2480B Serial 1-Wire® Line Driver
App Note 190 Challenge and Response with 1-Wire® SHA Devices
App Note 187 1-Wire Search Algorithm
App Note 178 Printed Circuit Board Identification Using 1-Wire® Products
App Note 155 1-Wire Software Resource Guide Device Description
App Note 154 Passwords in SHA Authentication
App Note 151 Maxim Digital Monetary Certificates
Tutorial 148 Guidelines for Reliable Long Line 1-Wire Networks
App Note 126 1-Wire Communication Through Software
App Note 74 Reading and Writing 1-Wire® Devices Through Serial Interfaces
App Note 27 Understanding and Using Cyclic Redundancy Checks with Maxim 1-Wire and iButton Products