Description: DS18B20 Digital Temperature sensor IC
DALLAS DS18B20 18B20 DC 3V 5V TO-92 Digital Temperature Sensor IC Chip Thermometer Temperature Controller Replace Thermocouple TMP100 LM75 DHT11 SHT15 LM35DZ TPA81 D6T Sensors
The DS18B20 digital thermometer provides 9-bit to 12-bit Celsius temperature measurements and has an alarm function with nonvolatile user-programmable upper and lower trigger points.
The DS18B20 communicates over a 1-Wire bus that by definition requires only one data line (and ground) for communication with a central microprocessor. It has an operating temperature range of -55°C to +125°C and is accurate to ±0.5°C over the range of -10°C to +85°C. In addition, the DS18B20 can derive power directly from the data line (“parasite power”), eliminating the need for an external power supply.
Each DS18B20 has a unique 64-bit serial code, which allows multiple DS18B20s to function on the same 1-Wire bus. Thus, it is simple to use one microprocessor to control many DS18B20s distributed over a large area.
DS18B20 Sensor Specifications
- Programmable Digital Temperature Sensor
- Communicates using 1-Wire method
- Operating voltage: 3V to 5V
- -10 to +85 Celsius with ~0.5 Celsius accuracy
- -55 to 125 Celsius with ~2.0 Celsius accuracy
- Accuracy: ±0.5°C
- Output Resolution: 9-bit to 12-bit (programmable)
- Unique 64-bit address enables multiplexing
- Conversion time: 750ms at 12-bit
- Programmable alarm options
- Available as To-92, SOP and even as a waterproof sensor
Note: Read further to know why these parameters are important. Also the DS18B20 datasheet can be found at the bottom of the page
Alternative Temperature Sensors
Thermocouple, TMP100, LM75, DHT11, SHT15, LM35DZ, TPA81, D6T
DS18B20 Equivalent Sensors
Where to use DS18B20 Sensor
The DS18B20 is a 1-wire programmable Temperature sensor from maxim integrated. It is widely used to measure temperature in hard environments like in chemical solutions, mines or soil etc. The constriction of the sensor is rugged and also can be purchased with a waterproof option making the mounting process easy. It can measure a wide range of temperature from -55°C to +125° with a decent accuracy of ±5°C. Each sensor has a unique address and requires only one pin of the MCU to transfer data so it a very good choice for measuring temperature at multiple points without compromising much of your digital pins on the microcontroller.
How to use the DS18B20 Sensor
The sensor works with the method of 1-Wire communication. It requires only the data pin connected to the microcontroller with a pull up resistor and the other two pins are used for power as shown below.
The pull-up resistor is used to keep the line in high state when the bus is not in use. The temperature value measured by the sensor will be stored in a 2-byte register inside the sensor. This data can be read by the using the 1- wire method by sending in a sequence of data. There are two types of commands that are to be sent to read the values, one is a ROM command and the other is function command. The address value of each ROM memory along with the sequence is given in the datasheet below. You have to read through it to understand how to communicate with the sensor.
If you are planning to interface it with Arduino, then you need not worry about all these. You can develop the readily available library and use the in-built functions to access the data.
- Measuring temperature at hard environments
- Liquid temperature measurement
- Applications where temperature has to be measured at multiple points
- 1 x DALLAS DS18B20 18B20 DC 3V 5V TO-92 Digital Temperature Sensor IC Chip Thermometer Temperature Controller Replace Thermocouple TMP100 LM75 DHT11 SHT15 LM35DZ TPA81 D6T Sensors