Review on 🔌 Qunqi 5pack MP1584EN Ultra Small DC-DC Step-Down Adjustable Module Buck Converter - 3A Power Supply for Arduino, Supports 24V to 12V, 9V, 5V, and 3V by Jignesh Shaffer

Better than I expected and incredibly small. I received them in the mail and realized how incredibly small they are. I immediately assumed they couldn't handle a 5v relay board with 4 decent relays on it. This was for an Arduino project in my car. The relay board draws 0.31A continuously when all relays are on. As a test, I connected the MP1584EN board to a +12V power supply and set it to 5.1V with a potentiometer. I then connected the relay board and jumpers so that all the relays are on. I let it sit for an hour and took a thermal picture of the result. Needless to say I was happy to see that it was barely warm without overheating at all. He managed the continuous draw very well. I have attached photos for those who are curious. I don't know how hot it will run at 1.0+ - 1.5A but I expect it to be at the upper limit for continuous current. If I were using one with that much current draw I would be using a heatsink on two components that show heat on a thermal image. Just some thoughts.