I am too afraid to read analog signal from it until I am perfectly sure what I am doing (don't want to fry anything)
I wanted to use this schematics and would only replace a photo resistor with my temp sensor:
(i almost connected it to USB and uploaded my sketch but I decided in the last moment to ask here first :))
I wonder how can I know how strong resistor do I need? I don't know the current nor the voltage of sensor so I can't calculate resistance needed. Is the 1.7K_OHM_ resistor OK, as shown in the top image?
(also, ignore the speaker part, I just want to display the readings on screen)
Just try, it should be safe. Insert in your code couple lines to print debug messages on serial monitor, like: "reading temperature: " and "analogRead(0)".
Does your sensor has a polarity marking "+" or "-"?
No, it does not have the polarity marks so I suppose it doesn't matter - like with fotoresistor.
Ok, I will try then But how can I be sure next time? On what basis do you know?
Thank you. I thought the current might be too high coming in to Analog pin because there is no resistor in front.
Anyways, I got my readings and used a simple function to get out Celsius. However, the readings are not consistent. It varies from 16 to 26 but it's around 22 really. What might be causing it?
Do you know anything at all about the temp sensor? Can you provide a link to where you bought it?
I concur with Magician's view, you are unlikely to damage it in that circuit. However, it will probably only work one way round.
The 2-terminal active temp sensors I have come across before are best connected between ground and an Arduino pin, with a pullup resistor of around 2k between the pin and +5v. Those particular sensors regulate the voltage across themselves to 10mv per degree Kelvin. So at room temperature, they drop about 3v, giving you a reading of around 600 from the Arduino analog pin.
But how can I be sure next time? On what basis do you know?