Regarding accuracy, it's been about a decade, but I did some embedded projects related to accurate temperature measurements back in the day. From what I recall, anything sensor that is < $100 or so is going to be 5% margin of error at the very best, and regardless of price, you're going to have to calibrate it and figure out the curves in your ADC, it's not going to be linear. Additionally, just the act of measuring will heat your sensor slightly so that will need to be taken into account as well.
replyIn short, if you need less than a couple degrees of accuracy, it's going to take a bit of tinkering. I wouldn't trust a $1 sensor for a tropical fish tank, for example, but probably good enough for a home thermostat.
I've used these: https://sensirion.com/media/documents/213E6A3B/63A5A569/Data...
replyThey claim accuracy of +-0.2 c across a wide temperature range and in my use they seem to be. easy to find on a support board for under $10
That tracks somewhat with what I remember. I was working on process control for an industrial washing machine in a hot and humid environment. I think the extreme temp and humidity is what made it difficult, but those error margins do look great for the cost.
replyThe datasheet will gives you absolute best case scenario. Like current consumption in sleep mode, or what register to set for best accuracy. It does not mean the Firmware will do exactly that.
replyThe datasheet gives you the 3 sigma worst case for accuracy.
replyFor power consumption a system power tree needs to be constructed and that will set the bounds that firmware can achieve. That would be better than trusting the manufacturer but a real test is best.