I wanted to knock something up with the LM35 I had kicking around, I also had an 0-5v analog meter so it was a perfect match. It isn’t all that accurate, the meter is a class 2.5, and I am only reading in full degrees.
The readings from the LM35 don’t match up to a 0-5v signal of course, so an ATtiny85 is used to ‘translate’ and limit the range to 15 to 25 degrees celsius. The whole thing is USB powered so I am using the 1.1v internal voltage reference to make sure I get stable and meaningful analog readings.
Here is the code if you would like it and as always I am happy to answer questions. –