10Pcs Step-Down Power Supply Module Mini DC-DC 12-24V To 5V 3A Voltage Buck Converter Adjustable 1.8V 2.5V 3.3V 5V 9V 12V

These units work well but you are going to struggle a bit to get them working.First they are incredibly small which means the writing and solder pads are tiny too.Two ways of operating: By using the tiny variable pot, to adjust which voltage you select but this is where it gets tricky!The VAR setting is the default EVEN THOUGH THERE IS NO SOLDER BLOB over the pads for that! (Remember only one voltage can be used/selected)So ignore the VAR solder blobs and carry on by adjusting via the micro pot, your voltage.If you want to select a voltage as a FIXED entity you must crape away the little track round the top of the VAR blob! This kills the micro pot from interfering with your selected voltage. Remember to solder a blob over the small gap in your selected voltage.

Works a treat. Super fiddly but they work as they should. Just read other feedback about removing the variable voltage track…

Excellent little boards which can be used with the onboard potentiometer to set the output voltage or by cutting the track to it and using one of the fixed resistor solder bridges as discussed elsewhere and shown in my attached photos.If you cut the track, you can always restore the potentiometer using the top solder bridge.The EN (enable) connection can be left open circuit to let the onboard pull-up enable the output or shorted to ground using a mechanical switch or FET for output control e.g. from a voltage monitor on the input.With the track cut and the 5V bridge soldered, the output was stable from an 18V all the way down to 5.4V input with a ~ 500mA load.Marked down slightly as there was no need to have a track to cut given the presence of the solder bridge for the pot.

Works well

Arrived in a non antistatic bag, not ideal as the board is assembled but I would prefer to see some protection.the score marks are not deep enough so you have to force the break between the boards, this can cause components to crack.No technical data:-Pins are:-Vo - Voltage Output - what ever you set the resistors or potentiometer toGnd - Ground - common groundIn - Voltage Input - 0 - 22 Volts input referenced to GndEN - Enable pin - Pull to Gnd to switch off, Leave open or pull high to enableThe voltage settings, as per other users comments, if you do not do anything then the potentiometer will control the voltage. if you want a fixed output then you MUST cut the potentiometer out of circuit, see other peoples images.My findings:-Breaking the boards out, 2 were damaged out of the 10.Powering up the boards:-First board blew up, second board was no output, the rest gave a good output with a 12V input.After setting up on the test bench it would seem that the input MAXIMUM voltage is NOT 24V.. the tolerances on the design do not allow 24V input. ok for 12V input dropping to less but useless for 24V.

I am amazed that i get a pretty clean stable output from this thing. I needed 3.3v so I soldered the 3.3v jumper ando got 2.9v which i was able to dial in to a perfect 3.3 with the variable resistor on top of the board.Even drawing 400mw it held output voltage. Great for a space or weight critical application...

a great little board but default mode is adjustable - see photo1 Cut the track for fixed voltage2 solder across the desired voltage pads

I use these to power ESP32 devices from a boat's DC supply that can be between 12 and 15V and with a few capacitors they work very well.As others have pointed out the default is to set the voltage using the very small potentiometer, not a problem if you have a suitable tool, and this is my preferred method.Love the small size.I use right angle SIL pins and plug the board into a matching socket on my motherboard, allowing easy removal if required.