KOOBOOK 5Pcs DC DC Step Down Power Module 5-16V to 1.25V/1.5V/1.8V/2.5V/3.3V/5V 3A Adjustable Buck Voltage Converter Board

Slightly bigger than a postage stamp. I was able to fit them into a very tight space on a project. Don't know if they can actually handle 3 amps but that would be even more impressive.

I have used two of these so far, and they met my requirements for driving a small clock (5 V to 1.5 V) and powering some LED indicator lights (12 V to 5 V). Voltage output is a little noisy (+/- a few millivolts) which is not critical for me. They come in strips which have to be snapped apart. I have not run them long enough to speak about longevity, but they seem well made.

One was Dead on Arrival, I have used two others so far, so 30% failure rate currently. No way to mount them so makes it difficult to solder and use them in a design.

I am using this to supply 1.8V to my glow plug igniter from a 6.6V LiFe battery. Current through glow plug measures between 1.8 to 2.2 A which exactly what I expect.Simple to set to desired voltage. Just solder short the appropriate bridge. No potentiometer to set, and low risk of having your settings changed accidentally.

small board that is very easy to use. There are no instructions that come with it, and I could not find any online, but if you know enough about circuitry to use the board, its easy to figure out what is going on from the onboard labels.

I built my own AA battery replacement for a wall mounted clock using one of these DC DC Step Down Power Modules. The module required just 5 solder connections to take the 5.9V from a junk wall wart to the 1.5V battery voltage my wall clock needed. No more monthly battery changes.

I’ve bought this product 3 Separate times and each time this comes. I’m pissed. Not as advertised at all.

Not much more to say. 3 of these have been in use for nearly a month now, with no problems.