DS75
Digital Thermometer and Thermostat
www.maxim-ic.com
FEATURES
PIN ASSIGNMENT
Temperature Measurements Require No
External Components
8
VDD
A0
SDA
1
2
3
4
Measures Temperatures from -55°C to
+125°C (-67°F to +257°F)
±2°C Accuracy Over a -25°C to +100°C
Range
7
6
5
SCL
O.S.
GND
A1
A2
Thermometer Resolution is User-
Configurable from Nine (Default) to 12 Bits
(0.5°C to 0.0625°C Resolution)
9-Bit Conversion Time is 150ms (Max)
Thermostatic Settings are User-Definable
Data is Read/Written Via 2-Wire Serial
(Interface (SDA and SCL Pins)
DS75S+ (8-Pin SO — 150mil)
8
1
2
3
VDD
A0
SDA
SCL
O.S.
GND
7
6
5
A1
4
A2
Multidrop Capability Simplifies Distributed
Temperature-Sensing Applications
Wide Power-Supply Range (+2.7V to
+5.5V).
Pin/software Compatible with the LM75
Available in 8-Pin μMAX® and SO
Packages. See Table 1 for Ordering
Information
DS75U+ (μMAX)
PIN DESCRIPTION
SDA – Open-Drain Data I/O
SCL – Clock Input
GND – Ground
O.S. – Open-Drain Thermostat Output
Applications Include Personal Computers,
Cellular Base Stations, Office Equipment, or
Any Thermally Sensitive System
A0
A1
A2
– Address Input
– Address Input
– Address Input
V DD – Power Supply
DESCRIPTION
The DS75 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
DS75 defaults to 9-bit resolution for software compatibility with the LM75. Communication with the
DS75 is achieved via a simple 2–wire serial interface. Three address pins allow up to eight DS75 devices
to operate on the same 2–wire bus, which greatly simplifies distributed temperature sensing applications.
The DS75 thermostat has a dedicated open–drain output (O.S.) and programmable fault tolerance, which
allows 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 (TOS and THYST).
A block diagram of the DS75 is shown in Figure 1 and detailed pin descriptions are given in Table 2.
µMAX is a registered trademark of Maxim Integrated Products, Inc.
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