Allan,
The only thermal data TI can provide is in Section 6.4 Thermal Information of the datasheet, which also provides a link to this reference documentation. (
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Which is standardized according to the documentation to try to convey a similar message for all ICs.
This data can be used to estimate the Thermal Performance of the TPS650250 at full load by using the efficiency of DC-DC converters and the voltage drop across LDOs as the Power dissipated by the part internally.
However, this estimate needs to be compared against the true application. You can further estimate the true application by using a TPS650250EVM-447, by modifying the output voltages to those needed in the final design and applying the maximum load. A "heat gun" can be used to measure temperature at likely hot spots and a thermal camera can be used to find hot spots and create a contour map of heat, more or less.
Some of the thermal dissipation is highly dependent on layout, and the customer will also need to measure on their PCB to ensure the likely hot spots are not rising to unacceptable temperatures in the final application.
