The DS2502 1Kb Add-Only Memory 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 DS2502 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 (09h) plus 1Kb of EPROM which is user-programmable. The power to program and read the DS2502 is derived entirely from the 1-Wire communication line.
Features
- 1024 bits Electrically Programmable Read Only Memory (EPROM) communicates with the economy of one signal plus ground
- 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
- Built-in multidrop controller ensures compatibility with other MicroLAN products
- EPROM partitioned into four 256-bit pages for randomly accessing packetized data
- Each memory page can be permanently write-protected to prevent tampering
- Device is an "add only" memory where additional data can be programmed into EPROM without disturbing existing data
- Architecture allows software to patch data by superseding an old page in favor of a newly programmed page
- Reduces control, address, data, power, and programming signals to a single data pin
- Directly connects to a single port pin of a microprocessor and communicates at up to 16.3 kbits per second
- 8-bit family code specifies DS2502 communications requirements to reader
- Presence detector acknowledges when the reader first applies voltage
- Low cost TO-92 or 8-pin SO, SOT-23 (3-pin), TSOC and flip chip surface mount package
- Reads over a wide voltage range of 2.8V to 6.0V from -40°C to +85°C; programs at 11.5V to 12.0V from -40°C to +50°C
