Simplified Block Diagram
- 4096 bits of read/write nonvolatile (NV) memory organized as 16 pages of 256 bits each
- Eight memory pages with individual 64-bit secrets and 32-bit read-only nonrolling-over page write-cycle counters
- Secrets are write-only and have their own individual write-cycle counters
- On-chip 512-bit SHA-1 (FIPS 180-1, ISO/IEC 10118-3) engine to compute a 160-bit Message Authentication Codes (MAC) and generate page secrets
- Device can operate as a roaming iButton device or as coprocessor for a host computer
- 256-bit scratchpad ensures integrity of data transfer
- On-chip 16-bit CRC generator for safeguarding data transfers
- Overdrive mode boosts communication speed to 125kbps
- Operating temperature range from -40°C to +85°C
- Over 10 years of data retention
- Unique, factory-lasered and tested 64-bit registration number (8-bit family code + 48-bit serial number + 8-bit CRC tester) assures absolute traceability because no two parts are alike
- Multidrop controller for MicroLAN
- Digital identification and information by momentary contact
- Chip-based data carrier compactly stores information
- Data can be accessed while affixed to object
- Economically communicates to host with a single digital signal at 15.4kbps
- Standard 16mm diameter and 1-Wire protocol ensure compatibility with iButton family of devices
- For Electronic Payment at Local Transit Systems, Pay Phones, Parking Systems, or Vending Machines
- Photo ID Badges
- Printed circuit boards
The DS1963S, like other SRAM-based iButton devices, has an additional memory area called the scratchpad that acts as a buffer when writing to the main memory. The DS1963's scratchpad is also used for feeding data segments to the SHA-1 engine or receiving/comparing message authentication codes.
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 main memory. This process ensures data integrity in an environment that does not provide a reliable electric contact.
Each DS1963S has its own 64-bit ROM registration number that is factory lasered into the chip inside to provide a guaranteed unique identity for absolute traceability. The durable MicroCan package is highly resistant to environmental hazards such as dirt, moisture, and shock. Its compact coin-shaped profile is self-aligning with mating receptacles, allowing the DS1963S to be easily used by human operators. Accessories permit the DS1963S to be mounted on almost any surface including plastic key fobs, photo-ID badges and printed circuit boards.