I am making a battery bank for portable LED projects. The battery bank has a 5V 12A (60W) DC to DC converter DDR-60L-5. I would like to add some extra (nice to have) USB Female plugs to this battery box for any USB device that I might need in the future.

I assumed I could connect the USB 5V(+) to DDR-60L-5 5V(+) and USB GND(-) to DDR-60L-5 GND(-) and that would be all that is required.

After reading this article How do I design a 2A or more power supply for my consumer USB devices? I found that I need a resistor network to tell the devices to use more current. After watching this video about Building the ultimate USB power distribution system I am worried about protection per port of the UBS charging. Reading this article I am told that I need to add filtering-caps between Vcc and GND. I am now a little overwhelmed with all the things I SHOULD do.

My question is:

  • Is there an existing IC that I can use to add all the protections, high charging current, etc.. to a USB charging port?
  • What is the absolute minimum I can safely do to create a simple USB charger port?

Edit: I am using this power bank to power 5V LEDs strips, 12v LEDs strips and other electronics projects. The USB charging port is a 'nice to have' since I already have 5V available in the battery pack.


simulate this circuit – Schematic created using CircuitLab

  • 1
    \$\begingroup\$ Please don't built this. Please don't even imagine building it with a 48v battery. Buy one with the kind of reasonable battery they usually include. USB downstream port protectors are a component in their own right, capacitors have nothing to do with that - the thought that they might is a bit indicative of why tackling such a project is very premature. \$\endgroup\$ Commented Mar 10, 2019 at 22:18
  • \$\begingroup\$ That's a lot of power for a USB power bank. \$\endgroup\$
    – Hearth
    Commented Mar 10, 2019 at 22:18
  • \$\begingroup\$ I will update the question. 48V 20A is for the LED projects. This power bank is primarily used to power my art projects that need lot of power. The USB power charging is a nice to have. @ChrisStratton \$\endgroup\$ Commented Mar 10, 2019 at 22:23


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