Sometimes LM35 analog temperature sensors give inconsistent readings. Reading fluctuations are simply too high. Specially if LM35 sensor is connected using a cable that is a meter long or longer. There are some techniques tu compensate for those fluctuations and get more consistent readings.… Read the rest
Starting from hardware side of things, all components were tested separately on breadboard. Putting all this together in a manageable package is just a bit of work.
The compnents used here are:
1x Arduino Duemilanove board
Finally got this DS18B20 working. Actually three of them. And in two modes. Parasite power mode and main mode.
A 4.7K ohm resistor is the key.
Starting with the main mode, three wires are needed, as this sensor has three pins.
Datasheet is here http://datasheets.maxim-ic.com/en/ds/DS18B20.pdf.
Connection is almost simple.
Pin 1 to Arduino ground
Pin 2 to Arduino digital input
Pin 3 to Arduino 5V
And a 4.7K resistor between pin 2 and pin 3
Works with three wires, as seen on the followind illustration.
