Overview

The DS18B20 is a popular digital temperature sensor that communicates over a 1-Wire bus that has a very good accuracy (±0.5°C). I got this as a 3 pin THT component, so not a module.

Features:

• ±0.5°C Accuracy from -10°C to +85°C
• Programmable Resolution from 9 Bits to 12 Bits
• No External Components Required (well, a resistor is required for 1-Wire Bus)
• 1-Wire interface
• Unique 64-bit serial code
• 3.3V or 5V compatible

Test Status

• ✅ Basic Configuration

Wire-up

DS18B20	ESP32 DEVKIT	Notes
GND (#1)	GND
Vdd (#3)	3.3V
DQ (#2)	Any GPIO	Has to have 4.7K pullup resistor connected to 3.3V

• Component Pinout
• Wiring Up With MCU

Basic Configuration

This is the basic configuration. Pretty simple, I’m using GPIO13 as my 1-wire pin. Just make sure it has 4.7K pull-up resistor connected to 3.3V on it. If connected to Home Assistant this will show temperature there, and the temperature is updated every 2 minutes. Have a look in the log for the temperature.

esphome:
  name: my-ds18b20-sensor

esp32:
  board: esp32dev
  framework:
    type: esp-idf

logger:

substitutions:
  one_wire_pin: GPIO13

one_wire:
  - platform: gpio
    pin: ${one_wire_pin}

sensor:
  - platform: dallas_temp
    name: temperature
    device_class: temperature
    state_class: measurement
    icon: mdi:thermometer
    unit_of_measurement: °C
    update_interval: 120s

It is good idea to use correct/meaningful icon, unit of measurement, device and state class as in the example above. This ensures data is displayed nicely in Home Assistant: