DESCRIPTION

The DS1821 can function as a standalone thermostat with user-programmable trip-points or as 8-bit temperature sensor with a 1-Wire digital interface.  The thermostat trip-points are stored in nonvolatile memory, so DS1821 units can be programmed prior to system insertion for true standalone operation. The DS1821 has an operating temperature range of –55°C to +125°C and is accurate to ±1°C over a range of 0°C to +85°C.  Communication with the DS1821 is accomplished through the open-drain DQ pin; this pin also serves as the thermostat output.

FEATURES

-Requires no external components

-Unique 1-Wire® interface requires only one port pin for communication

-Operates over a -55°C to +125°C (-67°F to +257°F) temperature range

-Functions as a standalone thermostat with user-definable trip-points

ƒ-Provides 8-bit (1°C resolution) centigrade temperature measurements

-Accuracy is ±1°C over 0°C to +85°C range

-Converts temperature to a digital word in 1 second (max)

-Available in 3-pin PR35 and 8-pin SO packages

-Applications include thermostatic controls, industrial systems, consumer products, thermometers, or any thermally sensitive system