DS1963S SHA iButton www.iButton.com Button shape is self-aligning with cup- SPECIAL FEATURES shaped probes 4096 bits of read/write nonvolatile (NV) Durable stainless steel case engraved with memory organized as 16 pages of 256 bits registration number withstands harsh each environments Eight memory pages with individual 64-bit Easily affixed with self-stick adhesive secrets and 32-bit read-only non rolling-over backing, latched by its flange, or locked with page write cycle counters a ring pressed onto its rim Secrets are write-only and have their own Presence detector acknowledges when reader individual write cycle counters first applies voltage On-chip 512-bit SHA-1 (FIPS 180-1, Meets UL 913 (4th Edit.) Intrinsically Safe ISO/IEC 10118-3) engine to compute a 160- Apparatus, Approved under Entity Concept bit Message Authentication Codes (MAC) for use in Class I, Division 1, Group A, B, C and generate page secrets and D Locations (application pending) Device can operate as roaming iButton or as coprocessor for a host computer 256bit scratchpad ensures integrity of data F5 MicroCan transfer 5.89 On-chip 16-bit CRC generator for 0.51 safeguarding data transfers Overdrive mode boosts communication 16.25 speed to 125 kbits per second Operating temperature range from -20C to 51 18 17.35 +85C 000000FBC52B Over 10 years of data retention 1-Wire COMMON iButton FEATURES Unique, factorylasered and tested 64-bit IO GND registration number (8-bit family code + 48-bit serial number + 8-bit CRC tester) All dimensions are shown in millimeters assures absolute traceability because no two parts are alike ORDERING INFORMATION Multidrop controller for MicroLAN DS1963S F5 MicroCan Digital identification and information by momentary contact EXAMPLES OF ACCESSORIES Chip-based data carrier compactly stores DS9096P Self-Stick Adhesive Pad information DS9101 Multipurpose Clip Data can be accessed while affixed to object DS9093RA Mounting Lock Ring Economically communicates to host with a DS9093A Snap-In Fob single digital signal at 15.4 kbits per second DS9092 iButton Probe Standard 16 mm diameter and 1-Wire protocol ensure compatibility with iButton Device family iButton and 1-Wire are registered trademarks of Dallas Semiconductor. 1 of 37 021704DS1963S iButton DESCRIPTION The DS1963S Monetary iButton with SHA-1 Function is a rugged 4 kbit read/write data carrier that can be easily accessed with minimal hardware. Its NV memory acts as a localized database for public as well as protected data belonging to the owner of the device and the environment in which it is used. An integrated 512-bit SHA-1 engine can be activated to compute 160-bit message authentication codes (MAC) based on information stored in the device. Data is transferred serially via the 1-Wire protocol, which requires only a single data lead and a ground return. Using the TMEX file format (see Application Note 114) a single DS1963S can serve up to four independent applications, such as secure change purses for electronic payment at local transit systems, pay phones, parking systems or vending machines. The DS1963S is also intended to function as a coprocessor that assists the host in computing signatures, using a secure signing secret, when writing back the new balance to a roaming device after a purchase. The DS1963S, like other SRAM-based iButtons, has an additional memory area called the scratchpad that acts as a buffer when writing to the main memory. The DS1963s 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. SECURITY A system that uses mobile data carriers consists mainly of three components, 1) host computers that read and write data carriers, 2) the data carriers (slave devices) themselves, and 3) the users of the system who might be tempted to manipulate the data or to emulate the behavior of the data carrier. The DS1963S is designed to address all these areas of attacks without using any proprietary restricted algorithms. The security of the device is based on the Secure Hash Standard SHA-1, which is documented on the Internet at locations such as