TPS5430: TPS5430 load derating curve

I don't think we have any derating curves for that device. The thermal performance is mostly determined by PCB design and other external considerations anyway. To get a base line I checked your worst case condition 24 V input 13.9 V output at 2 A in Webench. Webbench calculates 19.4 deg. C. temperature increase based on 0.55 W power dissipation and theta J-A of 33 C/W for a junction temperature of 79.4 deg. C. You can use the Webench design and the Thermal tool within Webench to simulate your thermal conditions. I think this is much more useful than a simple derating curve. Let me know if this helps.