DS2502_07 Datasheet, PDF (1/22 Pages) Dallas Semiconductor – 1 kbit Add-Only Memory

10/21/
www.maxim-ic.com
FEATURES
ƒ 1024 bits Electrically Programmable Read
Only Memory (EPROM) communicates with
the economy of one signal plus ground
ƒ 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
ƒ Built-in multidrop controller ensures
compatibility with other MicroLAN products
ƒ EPROM partitioned into four 256-bit pages
for randomly accessing packetized data
ƒ Each memory page can be permanently
write-protected to prevent tampering
ƒ Device is an “add only” memory where
additional data can be programmed into
EPROM without disturbing existing data
ƒ Architecture allows software to patch data by
superseding an old page in favor of a newly
programmed page
ƒ Reduces control, address, data, power, and
programming signals to a single data pin
ƒ Directly connects to a single port pin of a
microprocessor and communicates at up to
16.3 kbits per second
ƒ 8-bit family code specifies DS2502
communications requirements to reader
ƒ Presence detector acknowledges when the
reader first applies voltage
ƒ Low cost TO-92 or 8-pin SO, SOT-23 (3-
pin), TSOC and flip chip surface mount
package
ƒ 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
DS2502
1 kbit Add-Only Memory
PIN ASSIGNMENT
TO-92
DS2502
NC 1
NC 2
DATA 3
GND 4
8 NC
7 NC
6 NC
5 NC
123
BOTTOM VIEW
8-PIN SO (150 MIL)
TSOC PACKAGE
GND 1
DATA 2
NC 3
6 NC
5 NC
4 NC
TOP VIEW
SOT-23 Package
Top View
3
09rr
1
2
1 = DATA; 2, 3 = GND
“rr” = Revision
09rrd
1
2
Flip Chip, Top View
with Laser Mark,
Contacts Not Visible.
“rrd” = Revision/Date
1 = DATA
2 = GND
See 56-G7010-001 for package outline.
NOTE: The leads of TO-92 packages on tape-
and-reel are formed to approximately 100 mil
(2.54 mm) spacing. For details refer to drawing
56-G0006-003.
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