DROK USB Buck Converter, 4pcs DC-DC Step Down Module 6-32V 12V 24V to 5V QC 3.0 Charging Module Power Supply Voltage Regulator Volt Transformer Board

I used this to run a Raspberry Pi 4B and a 5V DC fan off of a 12.8V LiFePO4 battery. The Raspberry Pi was connected to the USB output while the fan was connected to the screw terminals. I had no issues with voltage or current whatsoever.

Great little modules we use within our line of products to run a microcontroller off of 12v. Very low RF noise compared to other buck converters we have tested and stable voltage. We can't really speak as to how they work under high load, as we only draw about 20mA from them, but we load test each one at 2 amps for 30 seconds and I don't believe we've ever had a dud out of 100+. At the power levels we draw heat is not an issue at all but it would be important to test this for high draw applications. We typically see a power conversion efficiency of about 85% from 12v to 5v@2A when load testing. Module size is always extremely consistent, which is important as we insert them into an enclosure with extremely tight tolerances. We chose this module for our product because of the consistent specifications, low cost, and low noise which is important as our microcontroller generates audio for a radio.

Almost 1 & 1/2 years ago, I ordered a 10 pack of 3.2v, 50ah, Prismatic Lifepo4 cells from an online vendor. With 8 of those cells I built a 100 amp hour LiFEPO4 battery. But I had 2, 3.2v, 50ah cells remaining that I did not know what to do with. I started wondering if there was a USB module that would accept an input of a minimum of 6 volts to which I could connect the battery to charge and power USB devices. Then I discovered the DROK USB DC-DC Step Down Buck Converter capable of taking 6 volts minimum and converting it to a 5V QC 3.0 Charging Module. I read the reviews, good and bad...bad to see what people were complaining about, and decided to buy a set of 4. I figured that the converter module should work as a USB charging device when connected to the 2 remaining LiFEPO4 cells if the cells are wired in series to produce the required 6+ volts. (See the first picture of the 2 LiFEPO4 cells connected in series with one of the 2 connections coming from the converter module connected.) The second photo shows both wires connected, and the blue illuminated LED on the converter module. You can see "78% 10 m until full" on the screen of my phone. The third photo shows the charging symbol on the screen. It shows 79%. Sorry for the fuzziness of that picture. I used a few of the converter modules to charge my phone and tablet for quite a while over the last few days. I wanted to see how warm they would get. The converter module does get warm, but not too hot to handle...unlike another similar product that got far too hot to be safe. And that was only at about 1 amp of current output. I'll be submitting a brutally honest review on that one soon. I foresee finding an appropriate container in which I will cut holes for the 4 converter modules and the the 50 amp hour battery and use the power source for a portable mega-USB charging station. I'll upload pictures when I get around to making it. I am very happy that my idea panned out!

Make sure that you have a couple of phillips different sizes of screwdrivers for very small screws and needle nose pliers to hold the brass stanchions while you get the 8 screws in place. Screw in the bottom screws into the short stanchions first, otherwise you will have difficulties lining up the last of the screws with the fourth top stanchions. Otherwise this is a very nice piece of gear. Drok alway makes good stuff.

Works as it should. However, the use case would be drastically increased with a remote wire turn on/off function. Then just use a jumper to keep it bridged unless needed for those that don't need that functionality. This would open this device up to auto/mobile installs where battery drain will be a problem.

Great solution for providing the 5 volts needed by the Victron Lynx Distributor products! Product converts 12v supplied by RV battery to 5v required by Victron.

These boards "worked" under no load, and even under very low load (<200mA), but failed catastrophically under higher loads 250mA and up. The output voltage will bounce around uncontrollably, and the power light will blink. This is essentially the same as the HCW-P715 and XY-3606 boards. They are all based on a CX8571 controller. Maybe there were clones of the design where they work, these don't. If you want to test your to see if it is broken, don't just check the output voltage under no load. Put a 8-10 Ohm power resistor on the output and check that it doesn't start blinking with voltage going haywire. This is too bad, because otherwise the design looks solid. Edit: It looked like they used the wrong resistor values, but it turns out they just used weird ones with odd markings, but even swapping in the correct ones for the FB pin only adjusts the voltage to actually 5 instead of 5.25. It still doesn't work under load. Very frustrating.

At the risk of sounding like an A.I review , I have used Drok products in many situations and they always excel. In this case, I hooked this device up to my very accurate meter while connected to a deep cycle battery and the output was 5.244 volts. It is flawlessly powering a traffic camera in my car while wired to a 12 volt circuit in the windshield mirror so that no wires hang down towards the cigarette lighter. When switched on there is a tiny red led to indicate that it is energized. It is held in place by two sided tape as the back of it is smooth. It has a crude USB A ( the original larger USB ) outlet and two options for power input, a wire terminal and jack.