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USB hubs, how do they work? Answered

So I was looking on Instructables at diy USB hubs and noticed they all have one thing in common.  They all start with a premade USB hub, in modify the case.  Why is that?  I doing know how USB hubs work and I was wondering if someone could shine some light on the topic.  For charging things via USB, I know they can simply be hooked up in paralleland still charge, slower, but still charge.  Let's say I wanted to put multiple flash drives on one USB port in my computer.  I know that with pre-built hubs this is possible, but I don't know how to do it without buying something.  If I wanted to put, say two flash drives, on one USB port, could I simply hook them up in parallel?  Series?  Or would I need a special circuit?  If a circuit is needed, what circuit?  Any help would be greatly appreciated.



4 years ago

Not worth the trouble considering the cost of them on Ebay...

You need a speed translator and a circuit to control the power to the ports.

A hub powered by the computer can only have 4 ports as the supply rating from the PC is 500mA, each port needsa minimum of 100mA.

So a hub with 8 ports would need external power supply and one that is capable of delivering enough to each port.

If you just want the same 500mA the PC would offer that means an 8port hub needs a 4A power supply already.

You also want some sort of safety in it so that a faulty battery or short won't kill the hub or power supply.


4 years ago

Do a google image search for USB Hub Schematic and you'll get all the info you need.