20PCS MT3608 DC-DC Step Up Boost Power Converter 2A Module Adjustable Step Up Voltage Regulator Board Voltage 2-24V to 5V-28V Output Voltage

I received 10 boards and tested 1 of them and did not work with 4.1v input. No change in output voltage regardless of potentiometer. Tried two more boards and they are the same. The boards should work with greater than 2v but did not work. I am returning them no point of checking remaining 7 boards.After further testing none of the boards are defective. The issue is that you need to turn potentiometer at least 20~30 turns all the way both sides and at one point output voltage will increase. Turn until u hear click sound. If no change then turn opposite direction and it should work but many turns in that direction.

First one I tried - Turn the pot, turn the pot, turn the pot...no change in voltage and suddenly it blows up. I was not expecting that, almost had to change my undies.Tried second then third - Turn the pot, turn the pot, turn the pot...no change in voltage. Then all voltage drops out and I noticed that they pulled my power supply down to nothing.Fourth through tenth - Garbage can. I'm not wasting my time or risking my power supply for these.

I use these on a commercial/industrial product and have had no issues. They are used outside (in an enclosure) subject to outside temperatures. I use them to provide 18-24 volts from a 12VDC supply for 4-20mA sensor loops. The sensors just need a few mA, so these little boosters are so much more efficient than a separate 24V power supply. They take just a bit to get set (follow directions) but seem to hold voltage well in this application. We load test each one for 24 hours but haven't found any bad parts so far.

It didn't work out of box. VOUT reads a bit lower than VIN, suggesting the chip not switching. I tried to adjust the pot and no luck.After reading so many 1 star reviews with the same behavior I was a little worried.Then I checked the datasheet of the IC (MT3608), measured the layout of the board out, eventually figured it out.Is it a 100k pot and when out of the box it was adjusted so that VOUT is almost shorted to FB, in which case the IC won't be able to regulate FB to 0.6V, which is its desired setpoint.One might want to crank the pot all the way counterclockwise (oh boy it was a lot of turns) so that resistance between VOUT and FB is closer to 100k instead of 0 and then go from there.I then connected VOUT net to my electronic load for up to 5.2V@2A load and it handles that just fine.It does get uncomfortably hot when wattage is above 15w or so, you will want to validate for your application. Also the regulation linearity is just so so underload. But hey I paid 8 bucks for 10pcs so wouldn't complain too much.TLDR: Measure resistance between pot pin 2 (the pin in the middle) and VOUT. If too low (less than a couple kOhm or so), it's not likely to work as intended. Turn the pot counterclockwise until this resistance reads in 10kOhm or higher, then connect your VIN and adjust from there.

Using them to step up 5v to 12v to drive a fan worked great. I've only used/tested a few but they work. FYI It takes quite a few turns of the potentiometer before you see the output voltage change.

It is easy to assume they are defective, but they are not!!!!Once you know that it is a matter of trying (turning that pot) until you find the calibration spot, you can actually get it done!It is a poor design. I do not recommend it, unless you really need them and you are willing to put the effort on calibrating them.

I had a 12 volt auto light bar that fit perfectly on the bumper of my Traxxas TRX4, but the standard voltage of the 2S battery wouldn't keep the light on. This step up voltage booster works great and keeps the light on so I can see to drive in the dark.

The goal for these boards was to step up the voltage from 12V (11.6V measured with Fluke multimeter) to 24V with a maximum current of 0.1A for a small 5015 fan. These boards were never hooked up to a fan. Upon bench testing and adjusting, the first board had a reversed polarity output. The VOUT- showed +24V and the VOUT+ showed -24V. I triple and quadrupled checked that I didn't have any of my leads reversed and they all looked fine. I powered off my power supply and when I turned it back on, the product now showed 11.6V output and would not step up power at all. I chalked it up to a brain fart and tried a second board. The second board never stepped up power at all no matter how many adjustments I made on the potentiometer (believe me, I went end to end and was aware of the 20 turns necessary for adjustment). Then all of a sudden, the board caught fire and blew a component. They were only connected to a multimeter. I didn't bother testing any more converters after that. Avoid this product.

I had the desire to reliably control my Noctua 12V 0.6Amp fan, but when powered from the wall-mounted, socket with a USB port (5V, 3.1Amp max supply). The fan works brilliantly within the full voltage range between 5.2V-12V. I am very happy with the purchase as the unit does not heat up at all and is stone-cold even after 3h of continuous work. The pot is quite sensitive, circa 2 turns per VoltLittle side note: Comments sections are really entertaining: it appears that only a few people had sufficient grasp of knowledge, that from 4.2V LiPo battery, even if you connect four of those boost units, you will not get reliable 110V AC ;)On the other hand - always choose the boost applicable to the project. Happy tinkering, guys.

I use these module in a product I sell. I need a source of 20V from the internal 12V supply.They are simple, convenient, readily available and inexpensive.So far, they have been reliable and easy to use.