- Unique 1-Wire (r) 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 the data line. Power supply range is 3.0V to 5.5V
- Measures temperatures from -55 degrees celsius to +125 degrees celsius (-67 F to +257 F)
- +/-0.5 degrees accuracy from -10 to +85 degrees celsius
- Thermometer resolution is user-selectable from 9 to 12 bits
- Converts temperature to 12-bit digital word in 750ms (max.)
- User-definable non-volatile (NV) alarm settings
- Alarm search command identifies and addresses devices whose temperature is outside of programmed limits (temperature alarm condition)
- Available in 8-pin SO (150mil), 8-pin mu-SOP, and 3-pin TO-92 packages
- Software compatible with the DS1822
- Applications include thermostatic controls, industrial systems, consumer products, thermometers, or any thermally sensitive system
- Waterproof version available
The datasheet and other information about this chip is linked to here: http://datasheets.maxim-ic.com/en/ds/DS18B20.pdf
The High Temperature Waterproof DS18B20 is available from Adafruit.
The DS18B20 is available in three packages, TO-92, SO, and μSOP.
Pin Outs (from datasheet):
Below is the schematic from the datasheet for wiring the DS18B20 in both parasite power mode and with an external supply.
This image is of a simple circuit using an externally powered DS18B20 with an Arduino microcontroller (Source: http://bildr.org/2011/07/ds18b20-arduino/).
Library & Code Examples
The Dallas Temperature Control Library provides an easy-to-use interface for the DS18B20. The library is currently at version 3.7.2 and can be downloaded from http://milesburton.com/Dallas_Temperature_Control_Library. The library also requires the OneWire library: http://www.pjrc.com/teensy/td_libs_OneWire.html
Included with the library are a variety of examples including code for reading a single or multiple sensors. Once you have downloaded and installed the library the examples will be available through the Arduino IDE menu via File > Examples > Dallas Temperature Control.
The library provides a variety of functions, including searching for sensors attached to a data line, retrieving their address, setting their resolution and retrieving data in either Celsius or Fahrenheit.
Temperature, Thermometer, Hot, Heat, Cold, Cool, Farenheit, Celsius, Degrees, Weather, Environment, Digital