Hope I'm posting this in the right place.

So I'd like to get a cheap unpowered USB hub, connect its data leads to a USB port on the computer, and connect its 0V and 5V leads to a separate power source, one that can tolerate higher currents than the connections coming out of the computer.

The idea is that this would make it in effect a powered hub, and I could plug into it a set of USB peripherals that would otherwise just be too powerful (in combination) to get all their juice from the one USB connection to the computer.

Would this work?

Hello and welcome
Looks like (on paper) it will

Question though (aside for the excitement that comes with tweaking hardware): A powered USB hub with 7 ports, costs less than 30€ in the Netherlands, and it can't be that more expensive in Ireland. Certainly far cheaper than a BBQed system...

I agree George, get a proper mains powered hub hemflit.

Thanks guys! I guess I sort of expected this would work, but it's reassuring to hear someone confirm it.

I never would have thought to look on Wikipedia; the article you pointed me to does have one paragraph that got me thinking:

This implies that in what I'm trying to do, a clever hub should end up asking the computer "can I use more power" and the computer replying "no" and then the hub would just refuse to run the peripherals at all, though in reality there's plenty of power to go around. So when buying maybe I should hope to get a really dumb hub. Does that sound right?


The reason I'm thinking of this is that I'm looking into making a really small computer (like, really small) and I don't want to end up carrying four pieces of equipment with me all the time: the computer, the hub, and two separate wall warts to power them.

Ideally, I'd just take apart the shop-bought hub's case, stick the electronic part into the same packaging as the computer and treat it as one unit. (Powering the hub directly from the computer's 5V input, itself connected to a power adapter.)

Am I maybe missing some more obvious solution?

I've also thought about just getting a small powered hub and connecting both it and the computer to one (slightly higher-powered) adapter. But the problem here is that for some reason makers of powered hubs just don't advertise the voltage they use. "It comes with its own adapter and that's all you need to know".

Any advice?

A few months back, I was investigating an issue on some Notebooks, and found an article about USB ports being damaged if the device connected required more power than the 500mA the port could deliver.

This in turn prompt me to a new research into Powered USB

Hope the article will assist you in your endeavors

PS: Just in case, make sure someone with a Current First Aid/CPR certification is nearby

Thanks George!