I finally got this DS18B20 to function. There were three of them. And in two different modes. Power mode and main mode are both available.
The crucial component is a 4.7K ohm resistor.
To begin with, three wires are required because this sensor has three pins.
The data sheet can be found Here:
The connection is quite effortless.
Pin 1 is connected to the Arduino's ground.
Arduino digital input pin 2
Arduino 5V Pin 3
In addition, a 4.7K resistor is connected between pins 2 and 3
Works with three wires, as shown in the illustration.
One wire is removed when using Parasite mode.
Pin 1 is connected to the Arduino's ground
Arduino digital input pin 2
Pin 3 is connected to the Arduino's ground (as is Pin 1)
A 4.7K resistor from pin 2 to 5V is also used
Perhaps the following illustration will be useful.
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Of course, several DS18B20s or other one-wire devices can be linked together as follows:
Herein lies the appeal of adopting digital thermometers. One Arduino pin can be utilized for several devices that communicate over a single wire. Actually, it's very similar to Ethernet. Each gadget has a distinct address.
A two-wire cable can also be used. These are normally far more common than three-wire wires. Digital 1-wire thermometers can also be used with longer wires. Cable-length-for-lm35-and-ds18b20 is a simple test.
A word of caution:
No DS18B20 pins should be left disconnected. Sometimes it works, sometimes it doesn't.
When used, avoid combining main mode and parasitic mode thermometers on the same pin. It works sometimes and does not function other times.
The DS18B20 can also be used outside. Some form of protection is recommended. I had one sensor outside, shielded like this, with a minimum temperature of around -30° C and a maximum temperature of about +35° C. So far, no issues.
For the past year, I've been using three DS18B20 thermometers, which occasionally fail to initialize properly. Especially after power outages. In that instance, a hard reset is beneficial.
CP2102 DS18B20
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