18B20 to -92 Temperature Sensor Chip
The DS18B20 temperature sensor provides 9 to 12–bit centigrade temperature measurements and has an alarm function with nonvolatile user-programmable upper and lower trigger points. The DS18B20-PAR does not need an external power supply because it derives power directly from the data line (“parasite power”). The DS18B20 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 ±0.5°C over a range of –10°C to +85°C.
Each DS18B20 has a unique 64-bit identification code, which allows multiple DS18B20 to function on the same 1–wire bus; thus, it is simple to use one microprocessor to control many DS18B20 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.