Don't mind me - I'm just bumping a message that's almost 2 years old.
So - I'm trying to make some sense of the math here. I have an LM34, and the math is obviously the same. I'm using Perl to connect and get the raw reading back from the LM34. .5 degrees isn't quite accurate, it's more like .488 mV, or 500mV/1024 (10 bits).
But that math doesn't make even the slightest sense to me. I've read the first post here upside down and sideway, and where are we getting 10 bits from? The documentation for the LM34 doesn't make any mention of this. Is it just a known thing about the arduino that if you hook up a 5V analog device that it has a range of 0 bits to 10 bits, thus it's always going to be a division of 500mV/1024?