DS1922L, DS1922T
Temperature Logger iButton
With 8kB Datalog Memory
www.maxim-ic.com
GENERAL DESCRIPTION
SPECIAL FEATURES
The DS1922L/T temperature logger iButtons® are
rugged, self-sufficient systems that measure
temperature and record the result in a protected
memory section. The recording is done at a user-
defined rate. A total of 8192 8-bit readings or 4096
16-bit readings taken at equidistant intervals ranging
from 1s to 273hrs can be stored. In addition to this,
there are 512 bytes of SRAM for storing application-
specific information and 64 bytes for calibration data.
A mission to collect data can be programmed to
begin immediately, or after a user-defined delay or
after a temperature alarm. Access to the memory and
control functions can be password protected. The
DS1922L/T is configured and communicates with a
host computing device through the serial 1-Wire®
protocol, which requires only a single data lead and a
ground return. Every DS1922L/T is factory-lasered
with a guaranteed unique 64-bit registration number
that allows for absolute traceability. The durable
stainless-steel package is highly resistant to
environmental hazards such as dirt, moisture, and
shock. Accessories permit the DS1922L/T to be
mounted on almost any object, including containers,
pallets, and bags.
Automatically Wakes up, Measures Tempera-
ture, and Stores Values in 8kB of Datalog
Memory in 8- or 16-Bit Format
Digital Thermometer Measures Temperature with
8-Bit (0.5°C) or 11-Bit (0.0625°C) Resolution
Accuracy of ±0.5°C from -10°C to +65°C
(DS1922L), ±0.5°C from +20°C to +75°C
(DS1922T) with Software Correction
Water resistant or waterproof if placed inside
DS9107 iButton capsule (Exceeds Water
Resistant 3 ATM requirements)
Sampling Rate from 1s up to 273hrs
Programmable Recording Start Delay After
Elapsed Time or Upon a Temperature Alarm Trip
Point
Programmable High and Low Trip Points for
Temperature Alarms
Quick Access to Alarmed Devices Through
1-Wire Conditional Search Function
512 Bytes of General-Purpose Plus 64 Bytes of
Calibration Memory
Two-Level Password Protection of All Memory
and Configuration Registers
Communicates to Host with a Single Digital
Signal at up to 15.4kbps at Standard Speed or
up to 125kbps in Overdrive Mode Using 1-Wire
Protocol
APPLICATIONS
Temperature Logging in Cold Chain, Food Safety,
Bio Science, and Pharmaceutical and Medical
Products
Operating Range: DS1922L: -40 to +85°C;
DS1922T: 0 to +125°C
High-Temperature Logging (Process Monitoring,
Industrial Temperature Monitoring)
PIN CONFIGURATION
5.89
0.51
ORDERING INFORMATION
PART
TEMP RANGE
PACKAGE
DS1922L-F5
DS1922T-F5
-40°C to +85°C F5 iButton
0°C to +125°C F5 iButton
®
16.25
A1
41
®
17.35
000000FBC52B
1-Wire®
See page 12 for Common iButton Features and
Examples of Accessories.
Commands, Registers, and Modes are capitalized for
clarity.
IO
GND
ALL DIMENSIONS ARE SHOWN IN MILLIMETERS.
iButton and 1-Wire are registered trademarks of Dallas Semiconductor,
Corp., a wholly owned subsidiary of Maxim Integrated Products, Inc.
Note: Some revisions of this device may incorporate deviations from published specifications known as errata. Multiple revisions of any device
may be simultaneously available through various sales channels. For information about device errata, click here: www.maxim-ic.com/errata.
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REV: 120407