OVERVIEW

The DS18B20 Digital Thermometer provides 9 to 12-bit (configurable) temperature readings which
indicate the temperature of the device.

Information is sent to/from the DS18B20 over a 1-Wire interface, so that only one wire (and ground)
needs to be connected from a central microprocessor to a DS18B20. Power for reading, writing, and
performing temperature conversions can be derived from the data line itself with no need for an external
power source.

Because each DS18B20 contains a unique silicon serial number, multiple DS18B20s can exist on the
same 1-Wire bus. This allows for placing temperature sensors in many different places. Applications
where this feature is useful include HVAC environmental controls, sensing temperatures inside buildings,
equipment or machinery, and process monitoring and control.

FEATURES

• Unique 1-Wire interface requires only one port pin for communication
• Multidrop capability simplifies distributed temperature sensing applications
• Requires no external components
• Can be powered from data line. Power supply range is 3.0V to 5.5V
• Zero standby power required
• Measures temperatures from -55°C to +125°C
• ±0.5°C accuracy from -10°C to +85°C
• Thermometer resolution is programmable from 9 to 12 bits
• Converts 12-bit temperature to digital word in 750 ms (max.)
• User-definable, nonvolatile temperature alarm settings
• Alarm search command identifies and addresses devices whose temperature is outside of programmed limits (temperature alarm condition)
• Applications include thermostatic controls, industrial systems, consumer products, thermometers, or any thermally sensitive system

Datasheet