DS75U Datasheet, PDF (1/14 Pages) Maxim Integrated Products – Digital Thermometer and Thermostat

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FEATURES
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 Over a -25°C to +100°C
Range
ƒ Thermometer Resolution is User-
Configurable from Nine (Default) to 12 Bits
(0.5°C to 0.0625°C Resolution)
ƒ 9-Bit Conversion Time is 150ms (Max)
ƒ Thermostatic Settings are User-Definable
ƒ Data is Read/Written Via 2-Wire Serial
(Interface (SDA and SCL Pins)
ƒ Multidrop Capability Simplifies Distributed
Temperature-Sensing Applications
ƒ Wide Power-Supply Range (+2.7V to
+5.5V).
ƒ Pin/software Compatible with the LM75
ƒ Available in 8-Pin μMAX^® and SO
Packages. See Table 1 for Ordering
Information
ƒ Applications Include Personal Computers,
Cellular Base Stations, Office Equipment, or
Any Thermally Sensitive System
DS75
Digital Thermometer and Thermostat
PIN ASSIGNMENT
SDA 1
8 V_DD
SCL 2
7 A₀
O.S. 3
6 A₁
GND 4
5 A₂
DS75S+ (8-Pin SO — 150mil)
SDA 1
SCL 2
O.S. ³
GND 4
8
V_DD
7
A₀
6
A₁
5
A₂
DS75U+ (μMAX)
PIN DESCRIPTION
SDA – Open-Drain Data I/O
SCL – Clock Input
GND – Ground
O.S. – Open-Drain Thermostat Output
A₀ – Address Input
A₁ – Address Input
A₂ – 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 (T_OS and T_HYST).
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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