DS28EC20_11 Datasheet, PDF (1/27 Pages) Maxim Integrated Products – 20Kb 1-Wire EEPROM

19-6067; Rev 3; 11/11
GENERAL DESCRIPTION
The DS28EC20 is a 20480-bit, 1-Wire^® EEPROM
organized as 80 memory pages of 256 bits each. An
additional page is set aside for control functions.
Data is written to a 32-byte scratchpad, verified, and
then copied to the EEPROM memory. As a special
feature, blocks of eight memory pages can be write
protected or put in EPROM-Emulation mode, where
bits can only be changed from a 1 to a 0 state. The
DS28EC20 communicates over the single-conductor
1-Wire bus. The communication follows the standard
1-Wire protocol. Each device has its own unalterable
and unique 64-bit ROM registration number. The
registration number is used to address the device in
a multidrop 1-Wire net environment.
APPLICATIONS
Device Authentication
IEEE 1451.4 Sensor TEDS
Ink/Toner Cartridges
Medical Sensors
PCB Identification
Wireless Base Stations
ORDERING INFORMATION
PART
TEMP RANGE PIN-PACKAGE
DS28EC20+
-40°C to +85C 3 TO-92
DS28EC20+T -40°C to +85C 3 TO-92, T&R
DS28EC20P+ -40°C to +85C 6 TSOC
DS28EC20P+T -40°C to +85C 6 TSOC, T&R
+Denotes a lead(Pb)-free/RoHS-compliant package.
T = Tape and reel.
TYPICAL OPERATING CIRCUIT
VCC
RPUP (300
to 2.2k)
PX.Y
µC
I/O
DS28EC20
GND
Commands, bytes, and modes are capitalized for clarity.
1-Wire is a registered trademark of Maxim Integrated Products, Inc.
DS28EC20
20Kb 1-Wire EEPROM
FEATURES
 20480 Bits of Nonvolatile (NV) EEPROM
Partitioned into Eighty 256-Bit Pages
 Individual 8-Page Groups of Memory Pages
(Blocks) can be Permanently Write Protected or
Put in OTP EPROM-Emulation Mode ("Write to
0")
 Read and Write Access Highly Backward-
Compatible to Legacy Devices (e.g., DS2433)
 256-Bit Scratchpad with Strict Read/Write
Protocols Ensures Integrity of Data Transfer
 200k Write/Erase Cycle Endurance at +25°C
 Unique Factory-Programmed 64-Bit Registration
Number Ensures Error-Free Device Selection
and Absolute Part Identity
 Switchpoint Hysteresis and Filtering to Optimize
Performance in the Presence of Noise
 Communicates to Host at 15.4kbps or 90kbps
Using 1-Wire Protocol
 Low-Cost TO-92 Package
 Operating Range: 5V ±5%, -40°C to +85°C
 Operating Range: 3.3V ±5%, 0°C to +70°C
(Standard Speed only)
 IEC 1000-4-2 Level 4 ESD Protection (8kV
Contact, 15kV Air, Typical) for I/O Pin
PIN CONFIGURATION
DALLAS
28EC20
123
123
TO-92
PIN 1 ---------- GND
PIN 2 ---------- I/O
PIN 3 ---------- N.C.
FOR TAPE-AND-
REEL THE LEADS
ARE FORMED TO
100 MILS (2.54mm)
SPACING VERSUS
50 MILS (1.27mm)
FOR BULK.
BOTTOM VIEW
TSOC, Top View
1
6 ^{PIN 1 ---------- N.C.}
PIN 2 ---------- I/O
2
5 _{PIN 3 ---------- GND}
3
4 _{PIN 4, 5, 6 ---- N.C.}
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