Digital Thermometer and Thermostat

The DS1721 digital thermometer and thermostat features ±1°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 DS1721 features three address inputs, allowing users to multidrop up to eight DS1721 devices on one bus.

The DS1721 offers thermostatic functionality with over-temperature (TH) and under-temperature (TL) 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 TH and it remains active until the temperature falls below TL.

The DS1721 is available in 150mil 8-pin SO (DS1721S) and 8-pin µMAX/µSOP (DS1721U) packages. For applications requiring higher precision, the DS1631 provides ±0.5°C accuracy and is functionally compatible with the DS1721.

Applications

* Alarm Systems * Fibre Channel * Instrumentation * Networking

* ±1°C accuracy from -10°C to +85°C

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

* 9- to 12-bit user-configurable resolution

* Dedicated thermostatic logic output

* Thermostatic settings are user-programmable

* Data is transferred over 2-wire/SMBus interface

* Three address inputs allow up to eight DS1721 to operate on one bus

* 2.7V to 5.5V supply range

* 150mil 8-pin SO (DS1721S) and 8-pin µMAX/µSOP (DS1721U) packages