I recently integrated a new fan into a new base for the airbrush pump I use for my laser cutter air assist.
The fan was a 120mm AC Infinity fan run on a 5V USB plug. I then became aware of a booster USB plug made by the same company. It’s a wall power plug with a USB port that puts out 6.5V instead of 5V. They claim this boosts the fan RPM 25% and thereby boosting the CFM some amount.
Instead of buying the plug I looked around and figured out I had the necessary stuff to make my own. The basis of the project is a LM2596 buck converter. I had an old 15V DC wall power plug that conveniently had a 5.5 x 2.1mm jack to go with the 5.5 x 2.1mm female panel mount port I had on hand. I’m using the buck converter to step down the voltage to 6.5V DC.
Mounted a USB A female port to a piece of solder board that will also hold the buck converter.
Using a thin piece of double sided tape I temporarily mounted the buck converter to the board. Used my dremel drill press to carefully drill out the holes for the connector solder holes (1mm) then the mounting holes (1/8").
The “H” section is glued in and serves several functions. It elevates the USB port higher, allows room for wires connecting to the buck converter and gives enough thickness for mounting screws.
Soldered all the connections and screwed down the board with 1/4" #2 screws
I made it so the voltage adjustment screw was accessible in case I ever want to repurpose this for something else. Also engraved in the specifications for this reason as well.
I have used these with great success. Don’t let the description fool you.
DROK voltage regulator input voltage range is DC 4.5-24V, adjustable range is 0.8-17V, fixed output are 1.8V, 2.5V, 3.3V, 5V, 9V, 12V that can be chosen on the back side. Output current is 3A max (please enhance cooling work when it is full load); when real tested input 12V and output is 1.5A, no need to add special system.
I think I had a 9V plug and I could have just made a voltage divider with some resistors.