Review on 🔌 PEMENOL 15W DC-DC Adjustable USB Power Supply Module - Convert Voltage from 5V to 3.3V, 9V, 12V, 24V, 30V - Step Up/Down Module with CVCC Buck Boost and Shell by Jaleel Pruitt

I am continually amazed by the practical and inexpensive electronics available to electronics enthusiasts (and in my case, school teachers). I plan to use this in my high school electronics class. The circuit board and acrylic sheets are professionally made and all smaller than a deck of cards. The 4-13V input can be connected via standard USB, micro USB, USB-C or custom cable pads. Output voltage and current are adjusted with very handy brass knobs on multi-turn potentiometers - no need to turn those little screwdrivers (thank goodness!). You have to turn the CC mode knob a bit before the processor will recognize that you are trying to set the current limit. Once this happens, the display will show "SET” mode. Leave it alone for a few seconds and it will return to normal mode. Remember that the USB output (marked in red) will have your chosen output voltage, so DO NOT plug in a USB device just like that. I think this will come in handy when you have phones that support fast charging. My phone doesn't have a fast charge function, so I can't comment on that. One more small note: the output current reading contains 9-10mA of what I believe to be the supply current (internal operating current). It's a little odd as I expect this to be in the input stream but not the output stream.