The DS2433 4Kb 1-Wire® EEPROM identifies and stores relevant information about the product to which it is associated. This lot or product specific information can be accessed with minimal interface, for example a single port pin of a microcontroller. The DS2433 consists of a factory-lasered registration number that includes a unique 48-bit serial number, an 8-bit CRC, and an 8-bit Family Code (23h) plus 4096 bits of user-programmable EEPROM. The power to read and write the DS2433 is derived entirely from the 1-Wire communication line. The memory is organized as sixteen pages of 256 bits each. The scratchpad is an additional page that acts as a buffer when writing to memory. Data is first written to the scratchpad where it may be read back for verification. A copy scratchpad command will then transfer the data to memory. This process insures data integrity when modifying the memory. The 64-bit registration number provides a guaranteed unique identity which allows for absolute traceability and acts as node address if multiple DS2433s are connected in parallel to form a local network. Data is transferred serially via the 1-Wire protocol which requires only a single data lead and a ground return. The PR-35 and SO packages provide a compact enclosure that allows standard assembly equipment to handle the device easily for attachment to printed circuit boards or wiring. Typical applications include storage of calibration constants, board identification and product revision status.