ESP32 - Temperature Sensor

This tutorial instructs you how to use ESP32 to read the temperature from DS18B20 temperature sensor and print it to Serial Monitor.

Hardware Used In This Tutorial

1	×	ESP-WROOM-32 Dev Module
1	×	Micro USB Cable
1	×	Temperature Sensor DS18B20
1	×	Jumper Wires
1	×	(Optional) 5V Power Adapter
1	×	(Optional) DC Power Jack
1	×	(Optional) ESP32 Screw Terminal Adapter

One of the following breadboard:

1	×	Full-sized 830-Point Breadboard
1	×	Half-sized 400-point Breadboard
1	×	Mini-sized 170-point Breadboard
1	×	All-sized Breadboard Kit

Disclosure: some of these links are affiliate links. We may earn a commission on your purchase at no extra cost to you. We appreciate it.

Introduction to One Wire Temperature Sensor - DS18B20

DS18B20 Temperature Sensor Pinout

DS18B20 temperature sensor has three pins:

GND pin: connect this pin to GND (0V)
VCC pin: connect this pin to VCC (5V or 3.3V)
DATA pin: is 1-Wire Data Bus. It should be connected to a digital pin on ESP32.

The DS18B20 sensor has two forms:

TO-92 package (looks similar to a transistor)
Waterproof probe. We use this form in this tutorial.

Connecting a DS18B20 temperature sensor with an Arduino often requires a pull-up resistor, which can be a hassle. However, some manufacturers have made the process simpler by offering a wiring adapter with a built-in pull-up resistor and a screw terminal block for easy connection.

Wiring Diagram between DS18B20 Temperature Sensor and ESP32

With breadboard

This image is created using Fritzing. Click to enlarge image

Wiring diagram with adapter (recommended)

This image is created using Fritzing. Click to enlarge image

Real wiring diagram with adapter

This image is created using Fritzing. Click to enlarge image

For ease of connection, it's advisable to purchase a DS18B20 sensor that comes with a wiring adapter equipped with a built-in resistor, eliminating the need for an additional resistor in the wiring.

ESP32 Code

/* * This ESP32 code is created by esp32io.com * * This ESP32 code is released in the public domain * * For more detail (instruction and wiring diagram), visit https://esp32io.com/tutorials/esp32-temperature-sensor */ #include <OneWire.h> #include <DallasTemperature.h> #define SENSOR_PIN 17 // ESP32 pin GIOP17 connected to DS18B20 sensor's DATA pin OneWire oneWire(SENSOR_PIN); DallasTemperature DS18B20(&oneWire); float tempC; // temperature in Celsius float tempF; // temperature in Fahrenheit void setup() { Serial.begin(9600); // initialize serial DS18B20.begin(); // initialize the DS18B20 sensor } void loop() { DS18B20.requestTemperatures(); // send the command to get temperatures tempC = DS18B20.getTempCByIndex(0); // read temperature in °C tempF = tempC * 9 / 5 + 32; // convert °C to °F Serial.print("Temperature: "); Serial.print(tempC); // print the temperature in °C Serial.print("°C"); Serial.print(" ~ "); // separator between °C and °F Serial.print(tempF); // print the temperature in °F Serial.println("°F"); delay(500); }

Quick Instructions

If this is the first time you use ESP32, see how to setup environment for ESP32 on Arduino IDE.
Do the wiring as above image.
Connect the ESP32 board to your PC via a micro USB cable
Open Arduino IDE on your PC.
Select the right ESP32 board (e.g. ESP32 Dev Module) and COM port.
On Arduino IDE, Navigate to Tools Manage Libraries

Type “OneWire” on the search box, then look for the OneWire library by Paul Stoffregen
Click Install button to install OneWire library.

Type “Dallas” on the search box, then look for the DallasTemperature library by Miles Burton.
Click Install button to install DallasTemperature library.

Copy the above code and paste it to Arduino IDE.
Compile and upload code to ESP32 board by clicking Upload button on Arduino IDE
Make the sensor hotter or colder by gripping the DS18B20 temerature sensor on your hand, or embedding it on hot and cold water.
See the result on Serial Monitor. It looks like the below:.

COM6

Send

Temperature: 26.31°C ~ 79.36°F Temperature: 26.44°C ~ 79.59°F Temperature: 26.50°C ~ 79.70°F Temperature: 26.56°C ~ 79.81°F Temperature: 27.06°C ~ 80.71°F Temperature: 27.75°C ~ 81.95°F Temperature: 28.37°C ~ 83.07°F Temperature: 29.00°C ~ 84.20°F Temperature: 29.56°C ~ 85.21°F Temperature: 30.00°C ~ 86.00°F Temperature: 30.31°C ~ 86.56°F Temperature: 30.62°C ~ 87.12°F Temperature: 30.87°C ~ 87.57°F

Autoscroll Show timestamp

Clear output

9600 baud

Newline

Video Tutorial

Making video is a time-consuming work. If the video tutorial is necessary for your learning, please let us know by subscribing to our YouTube channel , If the demand for video is high, we will make the video tutorial.

Learn More

※ OUR MESSAGES

As freelancers, We are AVAILABLE for HIRE. See how to outsource your project to us
If this tutorial is useful for you, please support us to make more tutorials.
Please feel free to share the link of this tutorial. However, Please do not use our content on any other websites. We invested a lot of effort and time to create the content, please respect our work!