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TPS7B92: TPS7B92

Abdelrahman Elnahas
Prodigy 40 points
Part Number: TPS7B92

Tool/software:

For this LDO , The I/P volatge is 24V , Vout = 5V

How to calculate the thermal increase of the IC at these conditions :-
@100 mA
@150 mA
@300 mA

  • 0
    TI__Genius 13640 points

    Hi Abdelrahman. 

    I am reviewing your query, and I will get back to you within 1-2 business days.

    Regards

    Ishaan

  • +1
    TI__Genius 13640 points

    By thermal increase, I assume you want to calculate the temperature of the junction of the device (Tj)?

    Power dissipation (Pd) = (VIN - VOUT) x IOUT

    Tj = Ta + Pd x RθJA where Ta = ambient temperature, RθJA = Junction-to-ambient thermal resistance (mentioned in the datasheet in section 5.4. Note that thermal performance results are based on the JEDEC standard of 2s2p PCB configuration. This value can change based on the board design. A thermally optimized design will yield a better i.e. lower RθJA)

    Assuming Ta = 25°C,

    For IOUT = 100 mA, Tj = 25 + (24-5)x0.1x207 = 418.3 °C

    For IOUT = 150 mA, Tj = 25 + (24-5)x0.15x207 = 614.95 °C

    For IOUT = 300 mA, Tj = 25 + (24-5)x0.3x207 = 1204.9 °C

    None of these temperatures are realistic because the device will enter thermal shutdown when Tj rises to 160 °C. Please reduce your VIN - VOUT difference