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TMP117: Lifetime at maximum temperature

Dawid Crivelli
Prodigy 20 points
Part Number: TMP117

Tool/software:

What is the specified lifetime of the device and at what temperature? 

We want to use the sensor for different healthcare scenarios that requires high accuracy (so we opt for the TMP117) from freezers to heaters. 

Will it stay in spec for 3 years both at elevated (120C), and low (-50C) temperatures?

  • 0
    TI__Expert 7170 points

    Hi Dawid,

    The TMP117 was qualified for HTOL at 125C for 1000 hours and we also spec drift for 1000 hours at 150C --> 0.03C. In terms of reliability, we are usually concerned with high temperature since this is physically what accelerates the life of a device due to electron flow. For these kind of assessments, one should usually consider an average use temperature which would be different from max temperature (120C). If the average use temperature of the device is lower, we can calculate an equivalent lifetime from the stress hours. Do you know what the average use temperature of the device will be?

    Best regards,

    Simon Rojas

  • 0 in reply to Simon Rojas Avila
    Prodigy 20 points

    What about the expected lifetime/temperature? It's probably not meant to live only 1000 hours at 125C, like the HTOL test suggests.

    We'd like to know what's the max expected temperature it can survive in for 3 years, so we can put a big disclaimer for our customers not to stick it at 150C continuously for years.

    The expected use case is a very low duty cycle usage, I would just like to know what are the limits for the worst-case continuous use

  • +1 in reply to Dawid Crivelli
    TI__Expert 7170 points

    Dawid,

    HTOL will not give the total lifetime of the device but it is used for accelerated life drift/performance. The important aspect to consider is that from TI's perspective, the device is rated for 0.1°C and max drift of 0.03°C at 1000 hours and 150°C (which is 30% error). Anything beyond this and TI would not be able to guarantee the temperature accuracy in the datasheet. 

    So in terms of absolute survival of the device functionality, yes it will be longer than 1000 hours at 150°C. But the device is only spec for these conditions.

    If we base the lifetime of the device using these conditions, the maximum temperature that would be equivalent to 1000 hours at 150°C in 3 years would be around 89°C. This means that you can run the device at 89°C for 3 years before the device falls out of temperature drift spec. I made this calculation using Arrhenius equation for acceleration factor.

    For more info on Af, please refer to the following document (page 24). Hope this helps.

    Best regards,

    Simon Rojas