DIGITAL TEMPERATURE SENSOR DS18B20

DIGITAL TEMPERATURE SENSOR DS18B20

The DS18B20 digital thermometer provides 9-bit to 12-bit Celsius temperature measurements and has an alarm function with nonvolatile
user-programmable upper and lower trigger points. The DS18B20 communicates over a 1-Wire bus that by definition requires only one data
line (and ground) for communication with a central microprocessor. In addition, the DS18B20 can derive power directly from the data line
(“parasite power”), eliminating the need for an external power supply.

Each DS18B20 has a unique 64-bit serial code, which allows multiple DS18B20s to function on the same 1-Wire bus. Thus, it is simple to use
one microprocessor to control many DS18B20s 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.

Features:

• Unique 1-Wire® interface requires only one port pin for communication

• Each device has a unique 64-bit serial code stored in an onboard ROM

• 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

• Measures temperatures from -55°C to 125°C (-67°F to 257°F)

• ±0.5°C accuracy from -10°C to 85°C

• Thermometer resolution is user-selectable from 9 to 12 bits

• Converts temperature to 12-bit digital word in 750ms (max.)

• User-definable nonvolatile (NV) 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

Technical Details

• Input Voltage: 3 – 5.5V

• Temperature Range: -55°C to 125°C

• Accuracy: ±0.5°C