Review on Adjustable Converter 1 25 36V Efficiency Regulator by Jonathan Roloff

I'm building an Arduino based lithium battery charger, mostly for fun and education, but also to recycle old laptop batteries into solar energy storage. I'm using these buck converters to step down 12V to 5V to power TP4056 charge controller boards that charge 18650 batteries. Each of the "battery modules" in the picture supports 4 batteries and can draw up to 20W. So if I put one of these buck converters on each module, I can split the power at 12V instead of 5V, greatly reducing current flow, wire size, and voltage drop. The buck converter's output voltage remains fairly stable, but drops as the load increases. . Adjusting the output voltage is easy, but make sure you turn off the potentiometer before connecting anything. The devices are delivered with a potentiometer set to full output voltage! With 12V input and output set 5V with no load, here are the drops I saw when applying a load: 0.0A - 5.0V 0.5A - 4.931A - 4.86V 2 A - 4.70V 3A - 4.55V Suddenly disconnecting the 3A load, the voltage returned to its original installation 5v. Using the "Max" function on my multimeter, I didn't see any spikes or over-corrections. They work really well to take a big step up from anything that uses a linear regulator for the ultimate in voltage regulation. The closer you can tune them to the final voltage required for the expected load, the less power the linear regulator has to dissipate. Based on my measurements they use a common base. So the negative output is not really needed as it is the same as the negative input. These are great little devices with many uses. Definitely recommended.