DS18B20 Temperature Sensor

The DS18B20 is a digital temperature sensor manufactured by (formerly Dallas Semiconductor). It is one of the most popular temperature sensors on the market and provides fairly high accuracy (±0.5 °C) over a large temperature range (-55 °C to + 125 °C). Because the operating voltage of the sensor is 3.0 to 5.5 V, you can use it with both the Arduino (which operates at 5 V), as well as with devices like the ESP32 and Raspberry Pi which have 3.3 V GPIO pins.

One of the main advantages of this sensor is that it requires only one digital pin of the Arduino for communication. The sensor communicates using the Dallas Semiconductor  protocol. This protocol works in a similar way as I2C, but with lower data rates and longer range.

Another advantage is that each DS18B20 sensor has a unique 64-bit serial code, which allows multiple sensors to function on the same 1-Wire bus. So you can read data from multiple sensors that are connected together with just one Arduino pin (see code examples below).

The resolution of the sensor can be set programmatically to 9, 10, 11, or 12 bits. This corresponds to temperature increments of 0.5 °C, 0.25 °C, 0.125 °C, and 0.0635 °C, respectively. The default resolution at power-up is 12-bit.