MAX31722 Datasheet, PDF (1/15 Pages) Maxim Integrated Products – Digital Thermometers and Thermostats with SPI/3-Wire Interface

19-5629; Rev 0; 11/10
Digital Thermometers and Thermostats
with SPI/3-Wire Interface
General Description
The MAX31722/MAX31723 digital thermometers and
thermostats with an SPI™/3-wire interface provide tem-
perature readings that indicate the device temperature.
No additional components are required; the devices
are truly temperature-to-digital converters. Temperature
readings are communicated from the device over an
SPI interface or a 3-wire serial interface. The choice of
interface is selectable by the user. For applications that
require greater temperature resolution, the user can
adjust the readout resolution from 9 to 12 bits. This is
particularly useful in applications where thermal runaway
conditions must be detected quickly. The thermostat has
a dedicated open-drain output (TOUT). Two thermostat
operating modes, comparator and interrupt, control ther-
mostat operation based on user-defined nonvolatile trip
points (THIGH and TLOW). Both devices feature a 1.7V to
3.7V supply rail.
Applications
Networking Equipment
Cellular Base Stations
Industrial Equipment
Any Thermally Sensitive Systems
Features
S Temperature Measurements Require No External
Components
S Measures Temperatures from -55NC to +125NC
S MAX31722 Thermometer Accuracy is ±2.0NC
S MAX31723 Thermometer Accuracy is ±0.5NC
S Thermometer Resolution is Configurable from 9
to 12 Bits (0.5NC to 0.0625NC Resolution)
S Thermostat Output with User-Defined Nonvolatile
Thresholds
S Data is Read from/Written to by SPI (Mode 0 and 2)
or 3-Wire Serial Interface
S 1.7V to 3.7V Power-Supply Range
S Available in 8-Pin µMAX^® Package
Ordering Information
PART
TEMP RANGE PIN-PACKAGE
MAX31722MUA+
MAX31722MUA+T
MAX31723MUA+
MAX31723MUA+T
-55NC to +125NC
-55NC to +125NC
-55NC to +125NC
-55NC to +125NC
8 FMAX
8 FMAX
8 FMAX
8 FMAX
+Denotes a lead(Pb)-free/RoHS-compliant package.
T = Tape and reel.
Functional Diagram
VDD
SDI
SDO
SCLK
CE
SERMODE
GND
PRECISION
VDD
REFERENCE
I/O CONTROL
AND
INPUT SENSE
OVERSAMPLING
MODULATOR
CONFIGURATION/
STATUS REGISTER
TEMPERATURE
REGISTER
THIGH AND TLOW
REGISTERS
DIGITAL
DECIMATOR
MAX31722
MAX31723
THERMOSTAT
COMPARATOR
TOUT
SPI is a trademark of Motorola, Inc.
µMAX is a registered trademark of Maxim Integrated Products, Inc.
________________________________________________________________ Maxim Integrated Products   1
For pricing, delivery, and ordering information, please contact Maxim Direct at 1-888-629-4642,
or visit Maxim’s website at www.maxim-ic.com.