Junction temperature
Estimate junction temperature from power, ambient and θJA; the LDO mode derives power from the voltage drop.
Reference θJA (°C/W, depends a lot on PCB copper):
Power850 mW
Junction Tj91 °C
Max allowed power1.417 W
LDO efficiency66 %
θJA depends on copper area and airflow; datasheet values use a JEDEC test board.
Tj = Ta + P · θJA P(LDO) = (Vin − Vout) · Iout + Vin · Iq
Results are for design reference only. Check the datasheet and measure.