TPS3838: Tj max

Muta

Intellectual 510 points

Part Number: TPS3838

Would you tell me the maximum junction temp(Tj max) for TPS3838L30DBVR.

My customer hope to know this value for thermal simulation.

Regards,

over 6 years ago

0 Michael_DeSando over 6 years ago

TI__Genius 12630 points

Muta,

The max junction temperature is 85C. The spec for Ta applies for Tj as Ta = Tj since this device has very low power dissipation. I hope this answers your question! Please let me know if you have additional questions. Thanks!

-Michael

0 Muta over 6 years ago in reply to Michael_DeSando

Intellectual 510 points

Hi Michael,
My customer have additional about your answer above.
Could you tell us why you offer same value as Tj=Ta ?

We know there are thermal resistance between junction and ambient. Also TI web show Tj=105C is minimum goal for TI’s semiconductor technologies.
www.ti.com/.../home
So I think your answer do not meet for TI's design guideline.

Regards.

0 Marshall_Beck over 6 years ago in reply to Muta

TI__Mastermind 35210 points

The device was defined for max, normal ambient temperature of +85degC.

The junction temperature can be estimated by the following equation below.

You can see as if the total power consumed by the deviced (P_T), is in the low microwatt or nanonwatt, then the second term of the equation below is zero and the T_J = T_C-top = T_A

Hopefully this helps.

Thermals resource:www.ti.com/.../slua844a.pdf

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TPS3838: Tj max