Those factors lead me to look for an alternative solution, which landed me squarely in buck-boost converter territory. Small inexpensive DC to DC converters that can either boost or reduce an input voltage. I’m not going to go into a great deal of detail on the devices themselves, but you can check out this Wikipedia article on them if you’re curious. Since my power needs are currently so small, a decent buck-boost converter with a decent power supply to feed it is all I need, so that’s the path I chose.
From the start I knew I wanted two of them, a small “portable” one I can also use as a backup, and a somewhat larger more convenient one to use much more often. The small portable one was easy, I just bought one on Amazon from a company I already knew and trusted, Drok. I have used some of their buck converters in the past and all of them worked perfectly, so I picked up the model you see below. It’s more than capable of handling anything I would ever be using it for, inexpensive, and small enough to fit in my electronics toolbox.
Buck Boost Converter: https://amzn.to/3tkr0i1
For my “project power supply” however, I wanted something a bit easier to use, and decided I would just build something simple around a buck-boost converter that I could quickly and easily adjust, connect and disconnect power, monitor power usage, and that I could mount in an enclosure but not take up a lot of space. I had originally wanted to buy a Drok unit like above, but they were sold out at the time, so I ended up going with a lesser-known seller, but it still worked just as well. The converter from “TXKEC” you see below is when I ended up buying.
Once it arrived, I tested it out to make sure it was working as intended and then looked for an enclosure to put it in so I could wire up a couple terminals, a power switch, and a barrel jack so I could use a standard brick power supply to run it. Lucky for me, I already had one on hand that ended up working out perfectly!
Enclosure: https://amzn.to/3UvRqsG
Buck Boost Converter: https://amzn.to/3fJ0cVb
Drok Buck Boost Converter: https://amzn.to/3FNI6Ml
For connectivity, I added a single banana plug style screw terminal and a single spring-joint clamp terminal. Like I said above, this will only be used on very low powered devices at 12V or less, so I don’t need anything “beefy”. For the power input I used a standard 5.5mmx2.5mm barrel jack so I could use many standard brick power supplies, with the one I chose being a 12V 36W 3A model, way more than I will ever need on this thing. From there I just had to modify the case to fit everything, add a power switch, wire it all up, make a couple cables using banana plugs, and make it all look nice. The end result is what you see below.
This was a very simple build to perform a very simple task. For the low powered devices I work with a vast majority of the time, it’s all I need. It works perfectly and allows me to easily select the desired voltage, monitor the input output voltage, as well as the output current, power, and capacity. Using the two terminals I decided to go with means I can easily connect it up to just about anything I need.
Overall, I’m very happy with my little “project power supply”. When the time comes and I need more power or more control, such as with classic computer repair or higher-powered devices, I’ll invest in a proper bench power supply, until then, this little guy is all I need.
Thanks for reading!