LQFP-64 thermal resistance Rjc

[Amaury LAINE]

Posted on September 07, 2017 at 17:52

Hello,

i would like to know what is the thermal resistance Rjc for a package LQFP-64. I didn't saw the value in the datasheet and i need it to know the Tj temperature, when PDmax is 0.1mW and my case is 90degrees.

Thanks you

[LMI2]

Posted on September 07, 2017 at 18:43

ST spreads or hides chip temperature data in many documents, it is difficult to find exact figures. But I would quess that the temperature is very close to the external temp. 0.1mW is a very small power. For a 746 chip LQFP100 it was 43 degrees per watt.

[Tesla DeLorean]

Posted on September 07, 2017 at 20:12

For critical commercial designs I'd strongly recommend working with an FAE who can get the answers, test data and characterization needed.

[waclawek.jan]

Posted on September 07, 2017 at 21:41

ST spreads or hides chip temperature data in many documents, it is difficult to find exact figures

I didn't find it particularly difficult to find; it's simply in the DS for the given model. Not that surprisingly, it's (slightly) dependent on particularities of each chip, not just the package itself. Two randomly selected examples:

JW