TPS54494: Operating ambient temperature range

Tool/software:

Hello,

I am going to use TPS54494PWP DC/DC converter on a board that will operate at an ambient/PCB temperature that can go slightly over 85°C.

I have a question related to the temperature ranges given in the datasheet:

The max operating ambient temperature is given to be 85°C. Usually when I make thermal considerations on my designs, I use as a limiting parameter the maximum junction temperature: I make sure that with the

• ambient temperature
• power dissipation
• thermal resistance Junction-Ambient (estimated by thermal probes / cameras and algebric considerations)

of my application, the Tj,max is not exceeded.

Usually, datasheets report deratings of performances if the ambient temperature is over a given limit and this is directly related to the argument above.

With the TPS54494, the story seems to be different, since the ambient temperaure itself is given as an Absolute Maximum Rating. Is there any reason behind this, not related to power dissipation nor to junction temperature?

Can I use this device in my application, even with Ta over 85°C, making sure that the Tj,max is not exceeded?

Many thanks, Alessio