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FEATURES
§ IEEE-approved factory programmed 64-bit
node address chip (EUI-64) with 768 bits
user-programmable OTP-EPROM
communicates with the economy of one
signal plus ground
§ Meets the node identification requirements of
IEEE Standard 1394-1995 (FireWire)
§ Unique, factory-lasered and tested 64-bit
registration number (8-bit family code 89H +
36-bit serial number + 12-bit UniqueWare
identifier 5E7H + 8-bit CRC tester) assures
absolute traceability because no two parts are
alike
§ Built-in multidrop controller ensures
compatibility with other MicroLAN products
§ Device is an “add only” memory where
additional data can be programmed into
EPROM without disturbing existing data
§ Reduces control, address, data, power and
programming signals to a single pin
§ Directly connects to a single port pin of a
microprocessor and communicates at up to
16.3k bits per second
§ Presence detector acknowledges when reader
first applies voltage
§ Low cost TO-92 or TSOC surface mount
packages
§ 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
3 2 1
PIN ASSIGNMENT
ORDERING INFORMATION
DS2502-E64 TO-92 package
DS2502P-E64 6-pin TSOC package
FireWireTM is a trademark of Apple Computer,
Inc.
GLOBAL INDENTIFIER DESCRIPTION
The DS2502-E64 is a variant of the DS2502 1024-bit Add-Only Memory. It differs from the standard
DS2502 in its custom ROM family code 89H, and the UniqueWare Identifier 5E7 in place of the upper 12
bits of the standard ROM serialization field. Otherwise, the electrical and logical behavior is identical to
that of the DS2502. For technical details please refer to the DS2502 data sheet. The first 32 bytes of the
DS2502-E64’s EPROM memory contain a globally unique 64-bit node address (EUI-64) and are writeprotected. The data structure follows the conventions of UniqueWare devices using Default Data
Structure (Figure 1).