Restrict the maximum IC junction temperature to 125°C under normal operating conditions. Calculate the maximum allowable dissipation, P_D(max), and keep the actual power dissipation less than or equal to P_D(max). The maximum-power-dissipation limit is determined using Equation 11.

Equation 11.

where

• T_A is the maximum ambient temperature for the application
• R_θJA is the junction-to-ambient thermal resistance given in Thermal Information

The TPS61023 comes in a SOT563 package. The real junction-to-ambient thermal resistance of the package greatly depends on the PCB type, layout. Using larger and thicker PCB copper for the power pads (GND, SW, and VOUT) to enhance the thermal performance. Using more vias connects the ground plate on the top layer and bottom layer around the IC without solder mask also improves the thermal capability.