The block diagram in Figure 1 shows the relationships between the major control and memory sections of the DS2505. The DS2505 has three main data components: 1) 64-bit lasered ROM, 2) 16384-bits EPROM Data Memory, and 3) 704 bits EPROM Status Memory.
FEATURES
16384 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 1-WireNet products
EPROM partitioned intosixty-four 256-bit pages for randomly accessing packetized data records
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 DS2505 communications requirements to reader
Presence detector acknowledges when the reader first applies voltage
Low cost TO-92 or 6-pin TSOC 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
