HiLetgo LM317 Buck Converter Module - Adjustable Voltage Regulator Power Supply - 10 Pack Review

I built a couple of LM317 regulators. And I've used several of them. These pre-made should be the deal of the century. You can't buy parts for one let alone 10 for the price.

Be very careful, never connect this module in reverse direction. I did it and almost lost an eye in the process. The capacitor exploded with such force, it was louder than a firecracker and I was bleeding from my eyebrow.

This is a great choice if you're into hardware hacking! The output voltage is stable even with large changes in the input voltage. It sounds like you need 1.50V more than the output for this to work, which is great! I like the compact size, the screw terminals and the mounting holes. I have a few bare LM317s but rarely use them because I need to add a potentiometer, cap, terminals etc; it just takes too long. I'll gladly take one of these instead!

Modules are very economical. They come without documentation but are easy to understand. There is no thermal paste between the heatsink and the LM317 regulator. I added thermal paste and changed the screw that holds the heatsink in place to keep it running efficiently. Because the heatsink is very small, be careful not to burn the regulator. I modified the module to work as a constant current source, not a constant voltage source.

I have bought 4-5 different converters with Arduinos in the last 4 years. Some were too bulky. Most of them do not provide an easy mechanism to secure the board in the project's electronics box. And some of them are very small and need to be soldered. This board is a great combination: big enough and screw-connected to be easy to work with, yet small enough to easily fit in a project box. Has holes for easy assembly. This will probably be my converter for future projects.