The downstream port power, VBUS, must be supplied by a source capable of supplying 5V and up to 900 mA per port. Downstream port power switches can be controlled by the TUSB8042A signals. It is also possible to leave the downstream port power always enabled.
A large bulk low-ESR capacitor of 22 µF or larger is required on each downstream port’s VBUS to limit in-rush current.
The ferrite beads on the VBUS pins of the downstream USB port connections are recommended for both ESD and EMI reasons. A 0.1µF capacitor on the USB connector side of the ferrite provides a low impedance path to ground for fast rise time ESD current that might have coupled onto the VBUS trace from the cable.