Need information TPS74401KTWRG3

It seems that, if this post is right, there is a mistake in the Datasheet. 

According to TPS74401 datasheet, ThetaJC(top) is 41.7degC/W.

Could you please advise because this is a really huge difference.

Jonathan,

The datasheet has the correct values in it. The datasheet was revised in December 2012 to reflect the new values, which was after the previous posting.

Regards,

David

Is this the same for TPS74901? The datasheet is wrong and the ThetaJC should be 41.7?

I have just noticed that it is totally impossible to have a value of ThetaJCtop higher than the value of ThetaJA. Moreover, a value of 41.7 degC/W is extremely high for a D2PAK package, which makes the use of this package totally useless...

Could you please check the exact source of those numbers?

Jonathan,

I will have to verify the results for the TPS74901 as it seems like an error. This will take some time to do.

Thank you for bringing this to my attention,

David

Jonathan,

The correct values for the EC table should be:

R_ΘJA = 31.6°C/W

R_ΘJC(top) = 35.9°C/W

R_ΘJB = 25.3°C/W

Ψ_JT  = 5.6°C/W

Ψ_JB = 23.8°C/W

Regards,

David

It still is really weird (even impossible) to have a lower ThetaJA than ThetaJC...

From what I know, ThetaJA is supposed to be ThetaJC + ThetaCA.

And from another point of view, the QFN package cannot be better than the D2PAK...

Jonathan,

There are several things that factor into the thermal characteristics of our devices. The following two application notes provided detailed explanations of the variables that affect the thermal characteristics:

http://www.ti.com/lit/an/spra953b/spra953b.pdf

http://www.ti.com/lit/an/sbva025/sbva025.pdf

Regards,

David