[Paul] recently purchased an inexpensive USB power pack ... Now you can’t just hook up the 22 ohm resistor to a 5V power supply for the sake of keeping it on — that would draw 1.1watts ...

The USB 2.0 PHY is a full-featured on-chip physical transceiver. It has Electro Static Discharge (ESD) protection and fully supports all OTG and host functionality. An optional charge pump generates a ...

Also, why was the output 4.7-5V, and why did my scope say 5.5V ... Check out a much more thorough analysis of this and pretty much every USB power supply cube by [Ken Shirriff].