DESCRIPTION
The DS1822-PAR digital thermometer provides 9- to 12-bit centigrade temperature measurements and
has an alarm function with nonvolatile (NV) user-programmable upper and lower trigger points. The
DS1822-PAR does not need an external power supply because it derives power directly from the data line
(“parasite power”). The DS1822-PAR communicates over a 1-Wire bus, which by definition requires
only one data line (and ground) for communication with a central microprocessor. It has an operating
temperature range of -55°C to +100°C and is accurate to ±2.0°C over a range of -10°C to +85°C.
Each DS1822-PAR has a unique 64-bit identification code, which allows multiple DS1822-PARs to
function on the same 1-Wire bus; thus, it is simple to use one microprocessor to control many
DS1822-PARs distributed over a large area. Applications that can benefit from this feature include
HVAC environmental controls, temperature monitoring systems inside buildings, equipment or
machinery, and process monitoring and control systems.