USB charging - WTF?

Question

Why would I want to leave my PC active for 3 hours to charge a little camera battery? (Note: easy solution found - buy a charger) But I am curious how this really works and the efficiency of going through a $1000 PC compared to a $40 wall charger.

Answer 1

I does not work ... there is no connection between the USB port on the camera and its battery.

Answer 2

it doesnt matter! the device is pulling +5v from the USB port. They device does not care if you feed it 5v from the computer, wall adapter or car adapter, if just wants to see that 5 volts on the correct USB pins.

Answer 3

(Your camera did not come with a charger?)

Some people don't turn their computer off.

Answer 4

Maybe you are using your PC for 3 hours.  It's not a necessity to use the USB port for charging if there are other means available, but if you happen to be using your PC (maybe to download photos from your camera) then you can charge it right there while you work.

USB 2.0 Specs  4.4 to 5.25 Volts, 2.25 Watts, and 500 milliamps.

If the device that being charged can use those parameters, then it's no less or more efficient.  It is a matter of convenience.