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Visitor II
August 8, 2022
Solved

Thermal resistance Rja and Rca of ST25R3916-AQWT

  • August 8, 2022
  • 2 replies
  • 2076 views

Hello,

I would like to receive information on the thermal characteristics of ST25R3916-AQWT.

Rja and Rca.

Let me know your input!

Cheers

Madhu

    This topic has been closed for replies.
    Best answer by Travis Palmer

    Hello Madhu,

    Rtheta_jc is specific to the device (more in detail it is specific to the used package).

    This is why we can very precisely can name this number.

    Rthetha_ja is specific to the device / package, PCB (size, amount of copper, number of layers, ...) and housing / airflow. This means, this number (Rthetha_ja) is specific to the application itself and we cannot do a general statement here.

    This is why we did this application note, showing how to setup the thermal model and measure / calculate the thermal resistance of each node (e.g. ja an ca on bottom and top).

    BR Travis

    2 replies

    Technical Moderator
    August 9, 2022

    Hi Madhu,

    did you find and check AN5584: ST25R39xx NFC reader thermal design?

    Best Regards, Ulysses

    MK.12Author
    Visitor II
    August 9, 2022

    Hello Ulysses,

    I did check the document. I was able to find Rtheta_jc as 16.95C. I dont think Rthetha_ja is not listed if I am right. So is it possible to get the correct value for Rthetha_ja?

    Cheers

    Madhu

    ST Employee
    August 11, 2022

    Hello Madhu,

    Rtheta_jc is specific to the device (more in detail it is specific to the used package).

    This is why we can very precisely can name this number.

    Rthetha_ja is specific to the device / package, PCB (size, amount of copper, number of layers, ...) and housing / airflow. This means, this number (Rthetha_ja) is specific to the application itself and we cannot do a general statement here.

    This is why we did this application note, showing how to setup the thermal model and measure / calculate the thermal resistance of each node (e.g. ja an ca on bottom and top).

    BR Travis