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DS18B20

ADIDS18B20

MPN: DS18B20+T&R
Analog Devices Inc./Maxim Integrated
Temperature Sensor Digital, Local -55°C ~ 125°C 12 b TO-92-3
NRND18,808 in stock
Datasheet Digi-Key Mouser Compare Prices

Overview

The DS18B20 is a digital thermometer that provides 9-bit to 12-bit Celsius temperature measurements over a 1-wire bus. It is unique for its ability to derive power directly from the data line ('parasite power'), eliminating the need for an external power supply. Each device has a unique 64-bit serial code, allowing multiple sensors to function on the same bus for distributed sensing applications.

Why Choose This Part

The primary advantage is the 1-Wire interface, which requires only one port pin for communication and can operate in parasite power mode. It offers selectable resolution from 9 to 12 bits and includes nonvolatile user-programmable alarm settings. The -55C to +125C range and +/-0.5C accuracy (from -10C to +85C) make it suitable for a wide variety of environments without external components.

Applications

HVAC Environmental Controls
Monitoring and regulating ambient temperatures in heating, ventilation, and air conditioning systems.
Industrial Process Monitoring
Tracking thermal conditions in machinery and industrial equipment where space for wiring is limited.
Distributed Temperature Sensing
Using the unique 64-bit ID to network dozens of sensors over a single long-distance wire for building automation.
Consumer Thermometers
Integration into handheld or fixed digital thermometers requiring high accuracy without complex calibration.

Key Specifications

Features Output Switch, Programmable Limit, Programmable Resolution
Resolution 12 b
Output Type 1-Wire
Sensor Type Digital, Local
Mounting Type Through Hole
Package / Case TO-226-3, TO-92-3 (TO-226AA) Formed Leads
Test Condition -10degC ~ 85degC (-55degC ~ 125degC)
Voltage - Supply 3V ~ 5.5V
Operating Temperature -55degC ~ 125degC
Supplier Device Package TO-92-3
Accuracy - Highest (Lowest) +/-0.5degC (+/-2degC)
Sensing Temperature - Local -55degC ~ 125degC

Getting Started

To interface with a microcontroller, connect the DQ pin to a GPIO with a 4.7k ohm pull-up resistor. Use the standard Maxim/Dallas 1-Wire protocol libraries available for platforms like Arduino (OneWire and DallasTemperature libraries) or STM32 HAL. Ensure the timing requirements for the reset pulse and bit slots are met as specified in the datasheet.

Also Consider

TMP36 ADIAnalog Devices Inc. - An analog alternative in the same TO-92 package that provides a linear voltage output proportional to temperature.
DS18S20 ADIAnalog Devices Inc. - A similar 1-Wire sensor with a fixed 9-bit resolution and faster conversion time for applications not requiring 12-bit precision.

Categories

Sensors > Temperature Sensors