June 30, 2025
Description
A compact, portable cooling solution that transforms your phone into a personal fan. Yes, you can buy something like that for cheap, but why would you. Maybe you have an old 5V hotend fan already lying around for this little project. Just a few electronic parts are necessary to run this fan with the power of your phone. The current draw of this small fan is very low (0.2A on mine). So, you can power the fan with your phone for quite a while.
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Don’t expect too much from the little fan – it only creates a light breeze! Get a Noctua NF-A4x10 5V, if you want a quiet fan. You need a USB-C plug where the Configuration Channel CC1 or CC2 is or can be pulled to ground with a 5.1kΩ resistor. Otherwise you won't get 5V from your phone. The 1N4007 diode provides flyback protection against voltage spikes. Both, the resistor and diode, are common and only cost a few cents. It’s probably not necessary to add the flyback diode to the small fan, but better safe than sorry. That being said, everything is at your own risk. Test your circuit on a USB-C power supply first.Â
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CC1 ------- [5.1kΩ Resistor] ------- GND
VBUS (+) Â -----------(red)----------- [Fan] ----------- (black)----------- (-) GND
  |---(stripe/cathode to +)--- [Flyback Diode] --------(anode to -)--------|
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Print with PLA and a layer height <0.2mm. Supports shouldn’t be necessary. The USB-C plug is held in place by a small spike. If you disassemble the plug from the 3D print, the small spike is probably going to break. If you want a different grille on the top part, you can simply change the infill pattern and percentage through the modifier in the 3mf file.
I added a variant where the bottom part has a modifiable grille. Be aware that this variant might reduce the air flow. Set a low infill density on the modifier.Â
License:
Creative Commons — Attribution — Noncommercial — Share Alike
Ratasich
