DS18B20 Temperature Sensor

Digital temperature sensor with 1-Wire interface

Digital temperature sensor with 1-Wire interface.

Pin names

VCC · Power

Positive voltage

DQ · Digital I/O

1-Wire data line (input/output)

GND · Ground

Ground

Attributes

temperature · string · default: "22"

Initial temperature value (celsius)

deviceID · string · default: "010203040506"

12-character hex device ID for the 1-Wire address

familyCode · string · default: "28"

1-Wire family code

Controlling the temperature

You can change the temperature value while the simulation is running. Click on the DS18B20 sensor and a small popup window will open. Use the temperature slider to change the value.

The temperature range is -55°C to 125°C.

Multiple sensors

You can connect multiple DS18B20 sensors to the same data pin. Each sensor must have a unique deviceID attribute. The 1-Wire protocol allows addressing individual sensors by their unique ID.

Example with three sensors:

{
  "parts": [
    { "type": "wokwi-ds18b20", "id": "temp1", "attrs": { "deviceID": "111111111111" } },
    { "type": "wokwi-ds18b20", "id": "temp2", "attrs": { "deviceID": "222222222222" } },
    { "type": "wokwi-ds18b20", "id": "temp3", "attrs": { "deviceID": "333333333333" } }
  ]
}

Arduino code example

#include <OneWire.h>
#include <DallasTemperature.h>

#define ONE_WIRE_BUS 2

OneWire oneWire(ONE_WIRE_BUS);
DallasTemperature sensors(&oneWire);

void setup() {
  Serial.begin(115200);
  sensors.begin();
}

void loop() {
  sensors.requestTemperatures();
  float tempC = sensors.getTempCByIndex(0);
  Serial.print("Temperature: ");
  Serial.print(tempC);
  Serial.println(" °C");
  delay(1000);
}

The DallasTemperature library cannot read temperatures of exactly -55°C due to a limitation in how the library detects disconnected sensors. If you need to read this specific temperature, use the OneWire library directly.

Automation controls

The temperature sensor can be controlled using Automation Scenarios. It exposes the following controls:

temperature · float

Set the temperature value in Celsius (between -55 and 125)

Simulator examples

• DS18B20 single sensor - Basic temperature reading with DallasTemperature library
• DS18B20 multiple sensors - Multiple sensors on a single bus