[Eclipse]

Perhaps you're right, but how can a usb generate enough voltage to do this?

https://en.m.wikipedia.org/wiki/Capacitor

It's an electrical component that's a little like a bucket. It stores the power, and when it's full it releases it all, and charges again. It's what's used in your camera flash, and why you have to charge up old disposable camera flashes. It's also used in light dimmers to regulate the current.

EDIT: Also, voltage and current are two completely different things.