USB Hub Question

Mikkl

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Jan 23, 2011
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Ok so there's USB hubs with their own power supply, and those that you just plug into a USB port on your PC.

Aren't there limitations to the type of hub that you just plug into the PC? I'm thinking if you have power hungry devices plugged into it, how much current can you draw from the single USB port on the PC?

Let's say you want an 8 port usb hub, and it's going to be used for charging phones etc. so you will be needing a decent current. Would it make any sense at all to take a usb hub of the type without its own power supply, modify it so the +5v and GND are hooked directly to the 5v rail on the PSU, and the data pins are connected to one of the PC's USB ports (you still want to be able to use the usb ports for other things than charging stuff). Or is the +5v on the USB already coming from the PSU? I figure the current output on a usb port might be limited for safety reasons?
 

Mikkl

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Jan 23, 2011
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18,510
Sorry but seems like my post is kind of vague so let me just clarify.

The point is to get a USB hub with many connectors able to supply somewhat powerhungry devices, without having to use a seperate power supply for the hub. But is it possible?