Rainbow Electronics DS75LX - Manual

1 of 13 050307
GENERAL DESCRIPTION
This low-voltage (1.7V to 3.7V) digital thermometer
and thermostat provides 9, 10, 11, or 12-bit digital
temperature readings over a -55°C to +125°C range
with
±2°C accuracy over a -25°C to +100°C range. At
power-up, the DS75LX defaults to 9-bit resolution for
software compatibility with the LM75. Communication
with the DS75LX is achieved through a simple 2-wire
serial interface. Three tri-state address pins allow up
to 27 DS75LX devices to operate on the same 2-wire
bus, which greatly simplifies distributed temperature-
sensing applications.
The DS75LX thermostat has a dedicated open-drain
output (O.S.) and programmable fault tolerance,
which allow the user to define the number of
consecutive error conditions that must occur before
O.S. is activated. There are two thermostatic
operating modes that control thermostat operation
based on user-defined trip-points (T
OS
and T
HYST
).
APPLICATIONS
Any Thermally Sensitive System
Cellular Base Stations
Telecom Switches and Routers
Servers
PIN CONFIGURATIONS
FEATURES
ƒ 1.7V to 3.7V Operating Range
ƒ Tri-State Address Pins Allow Up to 27 Unique
Bus Addresses
ƒ Temperature Measurements Require No
External Components
ƒ Measures Temperatures from -55°C to +125°C
(-67°F to +257°F)
ƒ ±2°C Accuracy from -25°C to +100°C
ƒ Thermometer Resolution Is User-
Configurable from 9 (Default) to 12 Bits (0.5°C
to 0.0625°C Resolution)
ƒ 9-Bit Conversion Time is 25ms (max)
ƒ Thermostatic Settings are User-Definable
ƒ Data is Read/Written Through 2-Wire Serial
Interface (SDA and SCL Pins)
ƒ Data Lines Filtered Internally for Noise
Immunity (50ns Deglitch)
ƒ Bus Timeout Feature Prevents Lockup
Problems on 2-Wire Interface
ƒ Multidrop Capability Simplifies Distributed
Temperature-Sensing Applications
ƒ Pin/Software Compatible with the LM75
ƒ Available in 8-Pin
μSOP (μMAX ® ) and SO
Packages
ORDERING INFORMATION
PART TEMP RANGE
PIN
PACKAGE
DS75LXS+ -55°C to +125°C
8 SO
(150 mils)
DS75LXS+T&R -55°C to +125°C
8 SO
(150 mils),
2500 Piece
DS75LXU+ -55°C to +125°C
8 µSOP
(µMAX)
DS75LXU+T&R -55°C to +125°C
8 µSOP
(µMAX),
3000 Piece
+ Denotes lead-free package.
T&R denotes tape-and-reel.
Note: A “+” symbol will also be marked on the package near the
pin 1 indicator.
µMAX is a registered trademark of Maxim Integrated Products, Inc.
DS75LX
Digital Thermometer and Thermostat
with Extended Addressing
www.maxim-ic.com
SO (150 mils)
SCL
V
DD
A
0
A
1
A
2
GND
O.S.
SDA
6
8
7
5
3
1
2
4
DS75
LX
μSOP/μMAX
SCL
V
DD
A
0
A
1
A
2
GND
O.S.
SDA
6
8
7
5
3
1
2
4
DS75
LX