The DS1822 is a digital thermometer with ±2°C accuracy over a -10°C to +85°C range. Data is read out over a 1-Wire® serial bus in 2"s complement format with 9 to 12 bits of resolution (user-programmable).
The DS1822 offers thermostatic functionality with over-temperature (TH) and under-temperature (TL) user-programmable setpoints stored in on-chip EEPROM. An internal flag is set when the measured temperature is greater than TH or less than TL. If thermostatic operation is not required, the two bytes of EEPROM reserved for TH and TL may be used for general-purpose nonvolatile storage.
Each DS1822 features a unique and unchangeable 64-bit silicon serial number, which serves as the bus address for the sensor. This allows multiple DS1822 devices to coexist on the same 1-Wire bus. The DS1822 may be locally powered via a 3.0V to 5.5V supply, or power can be derived from the 1-Wire data line ("parasite power").
The DS1822 is offered in 3-pin TO-92 (DS1822) and 150mil 8-pin SO (DS1822Z) packages. In addition, the DS1822 is available in a parasite-power only version, the DS1822-PAR. Also available is the high-precision DS18B20, which provides ±0.5°C accuracy and is software-compatible with the DS1822.
