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TPS27SA08-Q1: Transient Thermal Impedance in shorter data

Hideki Hayashi1
Genius 9360 points

Part Number: TPS27SA08-Q1
Other Parts Discussed in Thread: TPS1HC08-Q1

Hi team,

Do you have a Transient Thermal Impedance data with the time-axis from 1us?

My customer wants to see "x-axis from 1us and linear scale, y-axis with log scalge"

image.png

 

If you have a thermal simulation model, it'd be appreciated.

Best regards,

Hayashi

  • 0
    TI__Mastermind 34080 points

    Hi Hayashi-san,

    This transient thermal impedance graph is accurate to times >100us, as it is a package-level simulation rather than a silicon-level simulation.

    Why does the customer need this information? Perhaps we can solve this query another way.

    Thanks,

    Patrick

  • 0 in reply to Patrick Shalton
    TI__Genius 9360 points

    Hi Patrick,

    On customer's application, the load is capacitive (Electrolytic Capacitor: 2256uF) and will hit the current limit immediately after the device is conducted.

    So they want to calcurate how much Tj increase with a very short time. It is less than 10us, and will cause > 1kW.

    Customer understands <100us are not accurate, it'll be appreciated if you have data even they are less accuracy.

    Regards,

    Hayashi

  • 0 in reply to Hideki Hayashi1
    TI__Mastermind 34080 points

    Hi Hayashi-san,

    This device includes an energy limit that will most likely be triggered upon startup when trying to charge this large of a capacitor, so it will take longer to charge this capacitor. Can the customer use a device such as TPS1HC08-Q1 instead?

    In direct response to the customer's request, these devices have a relative thermal shutdown function that prevents the FET temperature from exceeding about 60C of the controller temperature. So the junction temperature won't exceed the controller temperature + 60C. For very short periods like the one described above, this will be limited to the ambient temperature + 60C.

    Thanks,

    Patrick

  • 0 in reply to Patrick Shalton
    TI__Genius 9360 points

    Hi Patrick,

    Even the device are protected by thermal shutdown function, customer want to know it for quantitative evaluation.

    Can you please provide the data which TI have? (Y-axis (Ztheta_TJ) is log, x-axis(time) is linear) You can send me a value table, I can make the graph by myself.

    And providing thermal simulation model are much better.

    Regards,

    Hayashi

  • 0 in reply to Hideki Hayashi1
    TI__Mastermind 34080 points

    Hi Hayashi-san,

    I will follow up with you on this via email.

    Thanks,

    Patrick