Rainbow Electronics DS1972 - Manual

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iButton DESCRIPTION
The DS1972 is a 1024-bit, 1-Wire
®
EEPROM
organized as four memory pages of 256 bits each in
a rugged iButton package. Data is written to an 8-
byte scratchpad, verified, and then copied to the
EEPROM memory. As a special feature, the four
memory pages can individually be write protected or
put in EPROM-emulation mode, where bits can only
be changed from a 1 to a 0 state. The DS1972
communicates over the single-conductor 1-Wire bus.
The communication follows the standard Dallas
Semiconductor 1-Wire protocol. Each device has its
own unalterable and unique 64-bit ROM registration
number that is factory lasered into the device. The
registration number is used to address the device in
a multidrop 1-Wire net environment.
APPLICATIONS
Access Control/Parking Meter
Work-In-Progress Tracking
Tool Management
Inventory Control
Maintenance/Inspection Data Storage
F5 AND F3 MicroCAN
0.51
5.89
IO
16.25
17.35
51 2D
0000006234FB
â
1-Wire в
в
3.10
IO GND
0.51
GND
F3 size F5 size Branding
SPECIAL FEATURES
§ 1024 Bits of EEPROM Memory Partitioned into
Four Pages of 256 Bits
§ Individual Memory Pages can be Permanently
Write Protected or Put in EPROM-Emulation
Mode ("Write to 0")
§ Switchpoint Hysteresis and Filtering to Optimize
Performance in the Presence of Noise
§ IEC 1000-4-2 Level 4 ESD Protection (8kV
Contact, 15kV Air, typical)
§ Reads and Writes Over a Wide Voltage Range of
2.8V to 5.25V from -40°C to +85°C
§ Communicates to Host with a Single Digital
Signal at 15.4kbps or 125kbps Using 1-Wire
Protocol
COMMON iButton FEATURES
§ Unique Factory-Lasered 64-Bit Registration
Number Assures Error-Free Device Selection
and Absolute Traceability Because No Two Parts
are Alike
§ Built-In Multidrop Controller for 1-Wire Net
§ Chip-Based Data Carrier Stores Digital Identifi-
cation and Information, Armored in a Durable
Stainless-Steel Case
§ Data can be Accessed While Affixed to Object
§ Button Shape is Self-Aligning with Cup-Shaped
Probes
§ Easily Affixed with Self-Stick Adhesive Backing,
Latched by its Flange, or Locked with a Ring
Pressed onto its Rim
§ Presence Detector Acknowledges when Reader
First Applies Voltage
§ Designed to meet UL#913 (4th Edit.); Intrinsically
Safe Apparatus: Under Entity Concept for use in
Class I, Division 1, Group A, B, C, and D
Locations, contact Dallas Semiconductor for
certification schedule
ORDERING INFORMATION
PART TEMP RANGE PIN-PACKAGE
DS1972-F5# -40°C to 85°C F5 iButton
DS1972-F3# -40°C to 85°C F3 iButton
# indicates RoHS complience
Contact factory lead-free compliance
Commands, Registers, and Modes are capitalized for
clarity.
IButton, 1-Wire, and MicroCAN are registered trademarks of Dallas
Semiconductor Corp.
DS1972
1024-Bit EEPROM iButton
www.maxim-ic.com