Based on the end application design and operational profile, the IDD and IDDIO currents could vary. Systems with more than 1 Watt power dissipation may require a product level thermal design. Care should be taken to keep Tj within specified limits. In the end applications, Tcase should be measured to estimate the operating junction temperature Tj. Tcase is normally measured at the center of the package top side surface. The thermal application note Semiconductor and IC package thermal metrics helps to understand the thermal metrics and definitions.