Author Options:

How much voltage comes from a standard usb cord? Answered



5 years ago

Perhaps maybe no one told these guys; but voltage is measured in volts, not milli-amps.

But loudmouth if you come back in here, I just want to tell you (belatedly) thank you for that information; I love how you explained that.

And Astroboy907, thank you too. But as I said earlier, the question was inquiring about "voltage"

The newer USB 3.0 ports even deliver up to 900mA and at least 150mA.

Most ports are CAPABLE of sourcing 500mA, but the specification will only allocate 100mA, unless the device attached asks for more.

5V DC. I think the standard says between 4.75v and 5.25/. Technically :)
Most computer ports source 500ma. Stuff like USB ports on your keyboard or the older USB only source 100ma. Most chargers can source 1amp. I think the iPad charges at 2amps (from a *special* usb)

But most any given USB now is 5v, 500ma. But it doesnt hurt to check specs

It is 5V DC, and I belive it is rated for a maximum output current of 500mA.

This is assuming it is coming from your PC or from a powered hub.

Some of those USB power products that have a USB power only jack coming from a cigarette lighter or wall outlet may be able to source greater current, but for those I would consult the specs.