Other Parts Discussed in Thread: LM62460
Dear TI,
I am working on the thermal design of LM62460 based converter and I have some questions regarding the IC thermal properties.
RthJB is given in datasheet and a note in layout chapter: "the package of this device dissipates heat through all pins". It means for me that all pins have a same thermal conduction properties (in point of view the junction-board path) and no one connected directly to the die like an exposed pad. Is it true, can be calculated all pins as an isothermal "area"? If not, than witch pins have better thermal resistance?
I want to use the high current pins (VIN, GND) to lead heat from the IC, similar than the example layout in datasheet. But this example a little bit strange for me, because VIN polygons are minimalized on top layer. If they have same thermal properties as GND pins, then bigger VIN polygons should be used to spread heat on top layer instead of the thinner inner layers.
summarizing my questions: Is there any pin that thermally connected to the die? VIN or GND pin has better thermal conduction/resistance?
Thanks in advance!