The WT6621 is a dual integrated power switch optimized for self-powered and bus-powered Universal Serial Bus (USB) applications. Few external components are necessary to satisfy USB requirements. With independent enable and error flag functions, the WT6621 can ease control the supplied power conditions of USB down stream; each switch channel can supplies up to 500mA to downstream devices; the switch low on-resistance meets USB voltage drop requirements; fault current is limited to typically 750mA, and a flag output is available to indicate fault conditions to the local USB controller. Additional features include thermal shutdown to prevent switch failure from high-current loads, undervoltage lockout (UVLO) to ensure there is a valid input voltage present, and 3.3V and 5V logic compatible enable inputs.