Digital Thermometer and Thermostat in SOT23

The DS1775 digital thermometer and thermostat is offered in a tiny 5-pin SOT-23 package and provides ±2°C accuracy over a -10°C to +85°C range. Thermometer data is read out over a 2-wire serial bus in 2's complement format with 9 to 12 bits of resolution (user-programmable). The DS1775 is available with eight different hard-wired addresses, allowing up to eight DS1775 devices to operate on the same bus. The eight versions of the DS1775 are:

Part Number

Address

DS1775R

000

DS1775R1

001

DS1775R2

010

DS1775R3

011

DS1775R4

100

DS1775R5

101

DS1775R6

110

DS1775R7

111

The DS1775 offers thermostatic functionality with over-temperature (TOS) and under-temperature (THYST) user-programmable trip-points stored in on-chip SRAM. The two trip-points provide programmable thermostat hysteresis: the thermostat output is asserted when the measured temperature exceeds TOS and it remains active until the temperature falls below THYST.

The DS1775 is functionally compatible with the DS75 and the LM75.

Applications

* Computer Graphics Systems * Industrial Instruments * Notebook Computers * Portable Terminals * Storage Area Networks (SANs)

* Temperature Measurements Require No External Components

* Measures Temperatures from -55°C to +125°C (-67°F to +257°F)

* ±2.0°C Thermometer Accuracy

* Thermometer Resolution is Configurable from 9 Bits to 12 Bits (0.5°C to 0.0625°C Resolution)

* User-Definable Thermostat Settings

* Data is Read From/Written to Through a 2-Wire Serial Interface

* 2.7V to 5.5V Wide Power-Supply Range

* Software Compatible with DS75 2-Wire Thermal Watchdog in Thermometer Mode

* Space-Conscious 5-Pin SOT23 Package with Low Thermal Time Constant