The DS2501 512-bit 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 DS2501 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 (11h) plus 512 bits of EPROM that is user-programmable.
It is a 512Kb add-only memory, often referred to as a 1-Wire EEPROM (Electrically Erasable Programmable Read-Only Memory). The 1-Wire protocol is a communication protocol developed by Dallas Semiconductor (now a part of Maxim Integrated) that allows for communication with devices over a single data line.
Data is transferred serially via the 1-Wire protocol which requires only a single data lead and a ground return. The entire device can be programmed and then write-protected if desired. Alternatively, the part may be programmed multiple times with new data being appended to, but not overwriting, existing data with each subsequent programming of the device.[…]
