I have a quick question: I have a USB battery pack, and I want to use that battery pack to power a little side project that I have.
Currently, this side project takes an input of 5V 4.8A, and I have seen USB Battery Packs that output 5V 2.4A on one port, and 5V 2.4A on another port for a total of 5V 4.8A.
I was wondering, if I ran two USB cables with their heads plugged into a 5V 2.4A (per port, 2 ports) USB battery pack, exposed the proper wires, would I be able to combine the red wire of one USB cable with the red wire of another USB cable and black wire of one USB cable and the black wire from the other USB cable to create an output of 5V 4.8A? sort of like what is happening below in which many wires are soldered together, and then connected into a single red
Otherwise, could I split the ends of the wire that extends from the side project (the item I am trying to power) into two, so: split the end of the red wire in half and the end of the black wire in half. Then, attach a red/black wire to each half respectively and in the end have two red wires flow into the 1 red input wire needed to charge?
Thanks,
A community member.
Best Answer
The specifics depend on the battery pack in question, but many usb power banks and usb supplies with multiple ports have their USB VCC output electronically tied together. The 2.4 limit is not a hard limit enforced by the power bank, rather it is a soft limit. The port is wired with the right resistor voltage divider on the usb data pairs, which tell the phone plugged into it that it's okay to draw up to that amount. This is generally the Apple standard. The phone then limits it's own draw.
That means you don't really need to use two usb ports. Drawing from the two ports help distribute the power through more copper which is nice though.
Note this applies to dumber power banks. Newer packs with Quick Charge or other features have more complicated circuitry and the same may not apply. See Ali's comment below.