Specifications

72 Control and Automation Solutions Guide
Featured Products
High-Accuracy Digital Temperature and Data
Loggers Oer Highest Data Integrity and
Temperature Recording
DS1922L/DS1922T, DS1922E
The DS1922L/T/E iButton temperature loggers are rugged, self-sucient systems
that measure temperature and record the result in a protected memory section.
The recording is done at a user-dened 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. Additionally, 512 bytes of SRAM store application-specic information and 64
bytes store calibration data. A mission to collect data can be programmed to begin
immediately, after a user-dened delay, or after a temperature alarm. Access to the
memory and control functions can be password protected. The DS1922 family is
congured by and communicates with a host-computing device through the serial
1-Wire protocol, which requires only a single data lead and a ground return. The
durable stainless steel package is highly resistant to environmental hazards such
as dirt, moisture, and shock. The version with the highest operating temperature
range (the DS1922E: +15°C to +140°C) can be used to monitor temperature in high-
temperature logging applications such as pasteurization or steam sterilization.
Benefits
• Sophisticated, flexible temperature
logging protects product integrity
◦ Automatically wakes up, measures
temperature and stores values in
8KB of data-log memory in 8- or
16-bit format
◦ Sampling rate from 1s up to 273hrs
◦ Programmable recording start
delay after elapsed time or upon a
temperature alarm trip point
• Precise, wide-range temperature
measurement ensures accuracy
◦ Digital thermometer measures
temperature with 8-bit (0.5°C) or
11-bit (0.0625°C) resolution
◦ ±0.5°C accuracy from -10°C to +65°C
(DS1922L), ±0.5°C from +20°C to
+75°C (DS1922T) with software
correction
• Rugged and small container provides
robustness and usage flexibility
◦ Strong stainless steel enclosure
◦ Complete solution in less than 0.1
cubic inch
• Safe, secure logging
◦ Water resistant or waterproof
if placed inside DS9107 iButton
capsule (exceeds water resistant 3
ATM requirements)
◦ Two-level password protection of all
memory and configuration registers
◦ Operating ranges: DS1922L: -40°C
to +85°C; DS1922T: 0°C to +125°C;
DS1922E: +15°C to 140°C
◦ Meets UL 913, 5th Ed., Rev. 1997-
02-24; intrinsically safe apparatus,
approved under entity concept for
use in Class I, Division 1, Group A, B,
C, and D locations
GENERAL-PURPOSE
SRAM
(512 BYTES)
CALIBRATION MEMORY
(64 BYTES)
REGISTER PAGES
(64 BYTES)
MEMORY
FUNCTION
CONTROL
64-BIT
LASERED
ROM
256-BIT
SCRATCHPAD
CONTROL
LOGIC
32.768kHz
OSCILLATOR
3V LITHIUM
IO
THERMAL
SENSE
ADC
DATA-LOG MEMORY
8KB
INTERNAL
TIMEKEEPING,
CONTROL REGISTERS,
AND COUNTERS
ROM
FUNCTION
CONTROL
1-Wire PORT
PARASITE-POWERED
CIRCUITRY
DS1922L
DS1922T