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REV: 111403
Note:
Some revisions of this device may incorporate deviations from published specifications known as errata. Multiple revisions of any device
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.
GENERAL DESCRIPTION
The DS2422 temperature/datalogger combines the
core functions of a fully featured datalogger in a
single chip. It includes a temperature sensor, real-
time clock (RTC), memory, 1-Wire
interface, and
serial interface for an analog-to-digital converter
(ADC) as well as control circuitry for a charge pump.
The ADC and the charge pump are peripherals that
can
be
added
to
build
dataloggers. Without external ADC, the DS2422
functions as a temperature logger only. The DS2422
measures the temperature and/or reads the ADC at a
user-defined rate. A total of 8192 8-bit readings or
4096 16-bit readings taken at equidistant intervals
ranging from 1s 273hrs can be stored.
application-specific
APPLICATIONS
Temperature Logging in Cold Chain, Food Safety,
and Bio Science
High-Temperature Logging (Process Monitoring,
industrial Temperature Monitoring)
General-Voltage Datalogging (Pressure, Humidity,
Light, Material Stress)
PIN CONFIGURATION
TEST_CG
VBAT
PUMP_ONZ
TEST_RX
NC
NC
NC
NC
TEST_SPLY
NC
GND
I/O
VPAD
SCLK
SDATA
CNVST
NC
NC
NC
NC
AGND
X1
ALARM
X2
1
2
3
4
5
6
7
8
9
10
11
12
24
23
22
21
20
19
18
17
16
15
14
13
FEATURES
Automatically Wakes Up, Measures Temperature
and/or Reads an External ADC and Stores
Values in 8kB of Datalog Memory in 8 or 16-Bit
Format
On-Chip Direct-to-Digital Temperature Converter
with 8-Bit (0.5°C) or 11-Bit (0.0625°C) Resolution
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 and Data Alarms
Quick Access to Alarmed Devices Through
1-Wire Conditional Search Function
512 Bytes of General-Purpose Memory Plus 64
Bytes of Calibration Memory
Two-Level Password Protection of all Memory
and Configuration Registers
Unique Factory-Lasered 64-Bit Registration
Number Assures Error-Free Device Selection
and Absolute Part Identity
Built-in Multidrop Controller Ensures Com-
patibility with Other Dallas Semiconductor 1-Wire
Net Products
Directly Connects to a Single Port Pin of a Mi-
croprocessor and Communicates at Up to
15.4kbps at Standard Speed or up to 125kbps in
Overdrive Mode
-40°C to +85°C Operating Range
2.8V to 3.6V Single-Supply Battery Operation
Low Power (1.2μA Standby, 350μA Active)
ORDERING INFORMATION
PART
TEMP RANGE
PIN-PACKAGE
24-lead, 300-mil
SO
DS2422S
-40 C to +85 C
Commands, Registers, and Modes are capitalized for
clarity.
DS2422
1-Wire Temperature/Datalogger
with 8kB Datalog Memory
www.maxim-ic.com
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1-Wire is a registered trademark of Dallas Semiconductor.