am335x USB hub

Yes, this one seems suitable.

Make sure you also check this wiki: http://processors.wiki.ti.com/index.php/AM335x_Schematic_Checklist#USB

Please be aware that TUSB2046 is a Full-Speed (12Mb/s) hub and does not support High-Speed (480Mb/s) operation. TI offers Full-Speed and SuperSpeed hubs, but does not offer a HighSpeed hub solution.

Giuseppe Zangari said:

ok thank you.

For me the main feature is the self-management of the overcurrent.

thanks

As Biser mentioned, most (all?) USB hubs will have over-current management for their downstream ports as it is the hub that actually controls power to downstream ports. AM335x will manage the over-current for the hub itself via the USBn_VBUS pin(s) so there is is no special functionality required from a hub perspective. Many hubs also support both per-port and ganged power delivery for downstream ports...personally I'd recommend implementing per-port power control as it provides the most robust solution in allowing the hub to only turn off the offending port in an over current scenario. A ganged power supply implementation doesn't have this level of granular control and will turn off all the downstream ports in the same situation.

Ok,

so for implementing a "per port" power controll all I need is the hub that I linked and to connect the USBn_VBUS pin to the hub?

Sorry but I'm trying to give some hint at my collegue that work on the hardware, I'm mostly involved in software :-)

thanks

For "per-port" power control of a hub, you will need a separate power control channel for each port of the hub. There are several ways to do this:

1. Use discrete power supplies for each port (TPS2051B)
2. Use 2x dual-channel power controllers (TPS2560)
3. Use a single 4-channel power controller (TPS2074)

You can refer to the relevant datasheet for implementation specifics, but for the most part every port's VBUS is controlled by a corresponding power enable and over-current pin on the hub via the controller itself.

For AM335x, it's important that we are able to control VBUS to our downstream port, or at least appear to do so. In other words, although the hub is controlling VBUS to the devices that are downstream of it, AM335x still expects to be able to turn on/off VBUS to our downstream port (which is the upstream port of the hub). Since it's not practical in an embedded hub configuration for us to actually turn on/off power to the hub (an embedded hub will likely be self-powered rather than bus-powered), the best way to meet this requirement is to simply route board 5V to the relevant USBn_VBUS pin through a switch that is USBn_DRVVBUS controlled. This allows AM335x to turn on/off "VBUS" without actually affecting the attached hub. The hub itself does not require 5V on it's upstream port when configured to be in self-powered mode.