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TPS7A4501-SP: Need list of what is toleranced in the worst case analysis pspice model provided

Part Number: TPS7A4501-SP

Hi,

I would to know a list of what is toleranced in the worst case analysis pspice model (TPS7A4501-SP PSpice Worst Case Analysis Model) that is provided on this page:

https://www.ti.com/product/TPS7A4501-SP

I can see a bunch of resistors with tolerances applied but don't know what that translates to (for example: gain, ref. voltage, etc.)

Any help would be appreciated. 

  • Raymond,

    I support this device and will be able to help you with your question.  Unfortunately, I am out of the office tomorrow.

    I will research this and get back with you Monday.

    Regards,

    Wade

  • Thanks for the reply Wade. 

    I eagerly await your reply on Monday.

  • Raymond,
    I was able to dig up some history on the creation of this WCA model.  This particular model was our first attempt at creating a comprehensive WCA model.   Unfortunately it is not easy to translate the toleranced parameters directly to device functional blocks.
    This model was based on and created from the transistor level spice model, using tables and pspice components to model actual device behavior and worst case effects.   The performance was modeled to align with bench data and full spice simulation.


    If this answers your question, please click "This Resolved My Issue"
    Regards,
    Wade

  • Wade,

    Is there anything further you or anyone at TI can do to find out what was toleranced? It is of extreme importance to us that such an expensive rad-hard part that is the basis for a power distribution system be properly correlated and documented.

    Thanks,

    Raymond

  • Raymond,

    I will check with our design team to see if there is additional data that can be provided.

    This may take a little time to work through.

    Regards,

    Wade

  • Raymond,

    I am still researching this.  The team that created this model is no longer on our team. 

    It is taking a little more time to get data and methodology.

    This may take several weeks to get better understanding.

    This was our first WCA model, and it does not fit our current (improved) methodology.  We may re-create the model in the future to meet our current methodology.   However, this will not occur for some time as it is fairly resource intensive.  Possibly mid 2021 for a new model.

    Regards,

    Wade

  • Raymond,

    I was able to confirm my prior statements.   The model that was created was not set up in a manner that will allow specific toleranced variables to directly relate to specific WCA modeled properties (aging, process or TID)

    I can say that Aging, TID, and process were included in the toleranced parameters.

    We will be evaluating the creation of a new model for this device that will be inline with our current methodology.  Timing is not set, but this would likely be 2H2021 for completion.

    There is some insight that can be gained  by reviewing the lot radiation test data.   When RHA material is procured, the group E data is provided for that lot.  This data can be used to understand behavior of some of the DC tested values.  There is data that can be used for Vref, load regulation, and dropout that should be beneficial for evaluating TID performance changes for various doses.

    Regards,

    Wade