Power Supply For USB Hub: Is 4.5v or 6v OK for something that listed as 5v?

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Power Supply For USB Hub: Is 4.5v or 6v OK for something that listed as 5v?

This isn't entirely related to hardware, however it has to do with a USB Hub connected to the hardware.

I have a USB hub that can take 5v DC. However, I have several switchable adaptors and both have 4.5v or 6v, but no 5v. My question is this: Would one of those options be acceptable or could it cause performance problems or overloads?

Thanks in advance.

G5 Rev B iMac - 250GB HD; 1.5GB RAM; Wireless Internet, Mac OS X (10.4.5)

Posted on Aug 22, 2006 11:23 PM

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Answer 1

Oct 12, 2006 3:35 AM in response to expataus

I have a USB hub that can take 5v DC. However, I
have several switchable adaptors and both have 4.5v
or 6v, but no 5v. My question is this: Would one of
those options be acceptable or could it cause
performance problems or overloads?

You must use a adaptor that provides 5 volts. 4.5 is not acceptable. 6 volts may damage some devices that are connected. Also, the power supply must be regulated, not the cheaper unregulated supplies. USB specifications say when operating at a full unit load, a minimum VBUS of 4.75 V is specified with a maximum of 5.25V

If connecting to a hub, a power supply would normally be expected to be able to supply 500mA per outlet, so for a 4 port hub, you should use a 2 amp supply.

If you really wanted to use your 6 volt supply, you could build a low dropout regulator to supply the 5 volts (however most common models handle only 1 amp). Personally, I'd use the right power supply.

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