LM35 Long Term Stability

Hi Ozer,

I'm sorry for the delay. I was a bit busy to respond the thread in a timely manner. Let me see if I can get the data for you.

Aaron

Hi Ozer,

The long term stability is in the datasheet on page 4.

I found the reliability data link below.

http://focus.ti.com/quality/docs/singlesearchresults.tsp?&templateId=5909&navigationId=11213&appType=folders&searchType=orderableOption&partialSearch=false&mtbfType=true&orderablePartNumber=LM35DZ/NOPB

Hope this helps. Let me know if you have further question.

Aaron

Hello Aaron,

Should I assume that the accuracy will change 0.08 C  after  every 1000h ?  I am confused with that.

Can you please explain ?

Thanks

Hello

I wonder  what  will be the accuracy  change  after using LM35 2 or 3 years ?  Does TI have any estimation ?

Thanks

Hi Ozer,We do not have any hard data to share with you other than the specificaiton that is in the datasheet for 1000hr. If you want to roughly calculate the drift for a different amount of time a standard rule of thumb is “For a time N × longer than 1000 hours, we expect the drift to be n = √N × the 1000-hour figure.”  For example after 4 years (let's say 36,000 hours) you would get 6 x 0.08'C = 0.48'C. If you believe the Arrhenius equation aging stuff and lets say you want to run at 300K since our testing was done at a much higher temperature you probably will not see more than 0.08'C of drift after 10 years. Sorry we can't give you any more information than that since we don't have any hard data to share with you. If you want to read why we do not do this type of testing take a look at this article by Bob Pease: http://electronicdesign.com/archive/what-s-all-long-term-stability-stuff-anyhow

It's pretty entertaining. BTW he was the designer of the LM35...

Take care,