• State Resolved
  • Locked Locked
  • Replies 3 replies
  • Answers 1 answer
  • Subscribers 62 subscribers
  • Views 283 views
  • Users 0 members are here
Support feedback
Options
Options
Related

This thread has been locked.

If you have a related question, please click the "Ask a related question" button in the top right corner. The newly created question will be automatically linked to this question.

TPS54527: Efficiency curve for 16Vin to 5Vout (2Aout)

Hideki Hayashi1
Expert 8720 points
Part Number: TPS54527


Hi team,

Do you have an efficiency curve more closer than the figure 7 in the datasheet (12Vin to 1.8, 2.5V, 3.3Vout) with the titled case in order to estimate junction temperature from case-top temperature?

Best regards,

Hideki

  • 0
    TI__Mastermind 27030 points

    Hi Hideki-san,

    That seems like the only curve available at the moment. You can extract the highest temp efficiency point (typically Iout max) and find total loss from it. Then after eliminating the inductor losses (core, conduction) you can get an idea of the IC losses from which you can estimate the junction temp using theta-ja (43.5C/W) from the datasheet (IC Tj = Ta + IC Loss * theta-ja) Alternatively, you can get a good estimate from WEBENCH tool for this device. 

    Thanks,
    Amod

  • 0 in reply to Amod Vaze
    TI__Expert 8720 points

    Hi Amod,

    Thanks for suggestion.

    Based on Semiconductor and IC Package Thermal Metrics, If I understand correctly, we should use ΨJT as thermal resistance for closer estimation in actual application. Is my understanding correct?

    Best regards,

    Hideki

  • +1 in reply to Hideki Hayashi1
    TI__Mastermind 27030 points

    Hi Hideki-san,

    Yes ΨJT can be used if you have the case temperature estimation. That would be more accurate.

    WEBENCH uses effective theta-ja which is a function of the EVM board typically as mentioned in the note you shared as well. So, you can still use WEBENCH junction temp estimation if you have a similar board to the EVM. If not, ideally, it would be best to do real measurements on your board and estimate junction temp using ΨJT.

    Thanks,

    Amod