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AM26LS33AM: MTTF Data AM26LS33AM

Part Number: AM26LS33AM

Is there an Arrhenius plot of MTTF (hours) vs junction temperature available for this die?

Reference Example:


Thanks,
-Jonathan

  • Jonathan,
    I am going to let our QA and Reliability engineer comment on this. I will let him know and he can comment on our design rules and reliability testing.

    Regards,
    Wade
  • Jonathan,

    I received feedback from our quality and reliability team.

    --

    A specific plot for this technology is not available.  In general TI processes are designed to exhibit a failure rate no worse than 50 FITs (Failures In Time or failure per billion device hours) in 100,000 power on hours when operating at nominal datasheet conditions excluding voltage transients.  The maximum operating temperature specified in the datasheet refers to the fact that the device is warranted to fully function up to that temperature.  No statement is made nor is any warranty implied as to reliability or operating lifetime.  Please see the TI DPPM/FIT/MTBF Estimator.  A general estimation of MTBF at various temperatures may be extrapolated using the data provided.   JESD85 “Methods for Calculating Failure Rates in Units of FITs” will provide more information on these calculations. 

    --

    If this answers your question, please click "Verify it as the answer"
    Regards,
    Wade

  • Jonathan, is there any reason why the data provided did not answer your question? Please elaborate.
    The MTBF estimator provides the data you are looking for, just not in a graphic form.

    Regards,
    Wade
  • Sorry Wade, I clicked on the link in order to bring up this web page.

    I looked into this a little more and came to this web page:
    www.ti.com/.../temperature-change-FIT.html
    www.ti.com/.../estimator.tsp

    The MTTF I get from the calculator by inputting the DPPM (56) and the temperatures (125°C Qualification & 155°C Application), the calculator estimated the packaged component to last 4.27 Million Hours

    Is this the proper way of using this calculator to get an estimate of MTTF for the packaged component? Would it be a conservative estimate with the bare die since the junction temperature is assumed to be a higher than the package?
  • I believe you are using the calculator correctly.

    However, exceeding the absolute max Tj of 150c would invalidate the warranty.   Higher temperatures may cause other activation energies to be more dominant.

    I will get confirmation from our reliability team, but I believe this to be correct.

    Regards,

    Wade

  • Wade,

    The 155°C is a hypothetical situation but can you find out from the reliability team which activation energy value to use if this is the case?

    In my application, I project the component to have a Tj of 135°C but it would be good to have knowledge for other parts that may get close to the max junction temperature specified on the datasheet.

    If you'd like to reference what I am working on, please see the attachment.



    In the lab test for the AM26LS33AMFKB, are the (qty) 36407 samples tested at 125°C package case temperature, ambient temperature, or is the 125°C specifying the junction temperature?

    The delta T rise of the component from 125°C ambient or case to the junction temperature may be close to or higher than 150°C for this package depending on the test environment.

    Thank you for your continued attention.

  • Hello Wade,

    Have you gotten a chance to review my previous post to verify with a reliability or thermal engineer?

    Thank you,

  • Jonathan,
    The feedback from reliability team:
    "The derating is credible within a limited range of temperatures (say about 10-15C) around the recommended max operating temperature. Extrapolations beyond the range have no validity, if the part has not been designed to last at those temperatures."

    The temperature that is reported as the test temp should be the oven ambient temp. However, this environment has high air flow that effectively reduces the ThetaJa parameter.

    This datasheet does not have the thermal parameters for either of the ceramic packages.
    I will request these to get modeled. This typically takes 2 weeks to complete.

    Regards,
    Wade
  • Hello Wade,

    Is there any updates on the Thermal Simulation Request?

    Thanks,

  • I requested both the FK and J packages for completeness. Currently I have the J package, but not the FK that you are using.
    I just requested a status update. I expect it should jump to top of queue and be completed shortly.

    Regards,
    Wade
  • They were able to complete it quickly.

    Note, that Theta Jc bottom is not normally provided.  However, it was modeled here along with the assumptions.

    Here are the parameters for both packages:

    For the FK package

    Theta JA-High K (standard datasheet value): 65.5

    Theta JC, top (standard datasheet value): 40.3

    Theta JB (standard datasheet value): 39.4

    Psi JT (standard datasheet value): 33.3

    Psi JB (standard datasheet value): 38.8

    Theta JC, bottom (standard datasheet value): 4.2 Modelling Assumptions: no PCB via, package body not soldered to PCB.

    For the J package

    Theta JA-High K (standard datasheet value): 74.6

    Theta JC, top (standard datasheet value): 37.6

    Theta JB (standard datasheet value): 56.1

    Psi JT (standard datasheet value): 26.4

    Psi JB (standard datasheet value): 58.5

    Theta JC, bottom (standard datasheet value): 13.1 Modelling Assumptions: no PCB via, package body not soldered to PCB.

    If this answers your question, please click "Verify it as the answer"

    Regards,

    Wade