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Transistor count in ICs

Carlos Moreno1
Intellectual 550 points
Other Parts Discussed in Thread: TPS62420

Hello,

For the purpose of failure rate calculations (as per IEC TR 62380), I need the transistor count for the ICs.  An approximate is ok (such as "between 100 and 200").

The chips I'm interested in are:  TPS65320, TPS62420, and TPS54618-Q1.

Even if the exact information is confidential, approximate values would do  (for now, I'm putting what I think is a conservative estimate of 1000 transistors --- I think it should be much less than that, right?)

Thanks,
Carlos
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  • 0
    TI__Guru*** 142730 points
    Please see the guidelines post at the top of this forum for tips on the title of your post. Please begin your post with the part number.

    This type of information is available on the quality tab of each product page, such as this one: www.ti.com/.../estimator.tsp
  • 0 in reply to Chris Glaser
    TI__Guru**** 191445 points

    Quality data for TPS54618-Q1:

    Early life failure rateMTBF / FITEarly life failure rate supporting dataMTBF / FIT supporting data
    Part numberELFR-DPPMMTBFFITConf level (%)Test temp (°C)Sample sizeFailsUsage temp (°C)Conf level (%)Activation energy (eV)Test temp (°C)Test duration (hours)Sample sizeFails
    TPS54618QRTERQ1 18 1x 10 10 0.1 60 125 50365 0 55 60.0 0.7 125 1000 134444 0
  • 0 in reply to Chris Glaser
    Intellectual 550 points
    Thanks Chris and John for your replies and the pointers!

    Apologies that I missed that! (I guess I was expecting to find this information as part of the datasheet and didn't pay close attention to the product's page).

    However, I'm a bit puzzled with this. IEC TR 62380 shows formulas to compute the FIT, but they heavily depend on the usage profile for the device (mostly, the temperatures and temperature variations --- how many cycles and the temperature variation (delta T) of each cycle plays a fundamental role on the "actual" failure rate (quotes around "actual" in that the number really is a probabilistic estimate based on a theoretical/mathematical model).

    The thing is: regardless of number of transistors, the estimate I'm getting with the average automotive usage profile suggested in IEC TR 62380 is far above the information I'm seeing here --- for the TPS65320, assuming 1000 transistors, I get around 50 FIT (the quality page for this one indicates 0.5 FIT).

    One possible explanation is: in the formula in the IEC document, there is a lambda_3 value that they describe as the "base failure rate for the package" --- for TSSOP 0.65mm pitch, 14-pins, the value they give is 0.44 --- *that one* is close to the 0.5 reported here, so I wonder if there's a direct relation to this?

    Any comments?

    Thanks,
    Carlos
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  • 0 in reply to Carlos Moreno1
    TI__Guru**** 191445 points

    I don't really know much about it.  I have never needed to perform those types of calculations and have only received a few requests over the years and the posted data seemed to satisfy those.  Let me see what I can find out.

  • 0 in reply to JohnTucker
    TI__Guru**** 191445 points
    I have submitted a request to the Quality Team. In the mean time there is some information available here that you may find useful:
    www.ti.com/.../reliabilityhome.page