JAJSU29 March 2024 ISOUSB211-Q1
ADVANCE INFORMATION
ISOUSB211-Q1 offers different power supply input options, including internal LDOs, that can be used to optimize thermal performance in HS mode. If the 3.3-V and 1.8-V supplies are supplied using external regulators, the power dissipated inside the ISOUSB chip is lower. The internal power dissipated, when taken with the junction-to-air thermal resistance defined in the Thermal Information table can be used to determine the junction temperature for a given ambient temperature. The junction temperature must not exceed 150°C. This section describes different power supply configurations for ISOUSB211-Q1 and explains how the power dissipated inside ISOUSB211-Q1 and the internal temperature rise can be calculated in each case.
For optimal thermal performance, connect small ground planes to the GNDx pins, and connect these planes to the ground layer with multiple vias as shown in Layout Example.