Hello Team,
My customer intend to use TPS715 for 24V to 5V_20mA, which has power loss 0.38W, since TPS715 is a SC70 package, can you tell if 0.38W for SC70 package is OK? or not recommended? in a case of 25C room temperature, what about the Tj looks like? is it possible to predict the thermal condition before customer use it to do the real test?
Thanks,
Martin
Hi Martin,
While layout does have an impact on thermal performance, we can estimate the thermal performance based on the information provided in the Thermal Information table.
At 0.38 W using a Thetaja of 253.8 C/W, we estimate that the junction temperature will be 96.4 C above the ambient. While 121.4 C does approach the 125 C rating of the TPS715, you are still within the operating temperature range.
Since you have ample headroom, one easy way to add a little margin for thermals would be to place a resistor in series before the LDO. The resistor will help spread the dissipation allowing the LDO to operate at a lower junction temperature.
Very Respectfully,
Ryan
