USB 5V to DC 12V

Thread Starter


Joined Jul 13, 2020

I purchased a 5V USB to 12V DC step up converter cable from Amazon. My intention was to use a USB power bank to power a 12V DC monitor, but I’m running into a bit of a problem.

When testing the cable with another device (video transmission receiver) it works fine. My USB power bank outputs 5V 2A which is what the manufacturer of the converter cable recommends. The transmission receiver has a power consumption rating of <6W. The cable has a max output current of 0.6A. All works fine, no problems.

However, when trying to power my monitor it doesn’t seem happy. It powered up but made quite a worrying buzzing sound, so I turned it off straight away. The monitor has a 12V DC input and a power consumption rating of ≤18W.

Is it too high of a power consumption to work with the converter cable. Is there a workaround?

Hope someone can help.



Joined Aug 21, 2008
Your USB power bank is good for 10 watts and it makes noise when you try to drive a load rated at less than 18 watts. Sounds reasonable to me. (humorously: the converter will not be 180% efficient, probably not even 80% efficient.