The DS18S20+T&R is a high precision 1 wire digital thermometer in 3 pin TO-92 package. The digital thermometer provides 9bit celsius temperature measurements and has an alarm function with non-volatile user-programmable upper and lower trigger points. It communicates over a 1 wire bus that requires only one data line and ground connections for communication with central microprocessor. It can derive power directly from the data line (parasite power) eliminating the need for an external power supply. It has an operating temperature range of -55°C to +125°C and is accurate to ±0.5°C over range of -10°C to +85°C. Each DS18S20 has a unique 64bit serial code which allows multiple DS18S20s to function on same 1 wire bus. Thus, it is simple to use one microprocessor to control many DS18S20s distributed over a large area. Typical applications include HVAC, environmental controls, temperature monitoring systems inside buildings, equipment or machinery & process monitoring and control systems.