HiLetgo 3pcs XL4015 5A DC to DC CC CV Lithium Battery Step Down Charging Board Led Power Converter Charger Step Down Module

all of them worked to charge my batteries just had to use a higher input voltage than I was planning to get the constant current to work

Sometime back I bought a camera for my truck. It records both front and and rear. moister got into the little black box that supplies the 12.5 volt to 5 volt (usb voltage) and shorted out the unit. Money down the drain until I found these neat little circuit boards. Used one and it almost fits in the plastic housing of the original unit under the dash. I am sure that I will find good use for the other two. Works perfect!

Great for my battery charger projectworked perfect.product well made.

All three boards I received tested good. As another purchaser mentioned, the terminals for POWER IN +/- and POWER OUT +/- are cheap and the screws are difficult to loosen. The potentiometers require many turns to make any changes to voltage or current, but this is desirable because it allows for minute adjustments. Ensure that voltage is adjusted BEFORE connecting a load to POWER OUT +/-, and current is adjusted AFTER connecting the load. Additionally, do NOT connect a load if the board is not powered because you risk damage to the circuitry.I used the boards to recharge 12v lead-acid batteries. So far, the only issue I've experienced is overheating. I mounted a cooling fan to the board and it's performing well. I supplied the board with a laptop charger with an output of 19.5v DC at 4.45A. The board is outputting 14.4v DC at 4.85A under load. I am still trying to determine exactly what the LEDs indicate. There are three, a blue, red, and a green. The red seems to fade out when the battery is near full charge. Nothing has blown up. Yet.

They're are quite a few varieties of these cc/cv charges controllers so if you're looking for specifics, be sure to research.I've got one working as a solar charge controller, another as a step down converter for my 12v devices and another as a cc/cv regulator for my motorcycle lithium battery. They've all been working for many, many hours and are still going strong. Had them for a few months at least.P.S. - Don't push them past 5A unless you are cooling them. If you even wanted to cool them at lower amperages it would probably extend their life.Anyhow, hope this helps. Cheers!