Finding the right voltage DC power supply can sometimes be difficult. Sure, there are standard supply voltages, such as 5, 9 and 12, but if you need something that’s different from one of these voltages, it can be a bit of a hassle to find a supply. Of course there are inexpensive variable output DC to DC converters on the internet, but sometimes it’s just fun to build your own.
In selecting a chip for the DC to DC boost converter, I decided on the MC34063. I decided on this IC for a few reasons; I have experience using them, they are quite inexpensive, and I had a nice stock of them already . This IC has been around for decades, and will do the combination of boost/buck/inverting making it quite versatile. This is actually the first IC I ever used, and my interest in DC to DC converters is what initially got me interested in electronics, so finally building a decent PCB using this IC was overdue.
I decided that I would make the board capable of supporting a barrel jack, as well screw terminals for the input. This way, it could be run from a 12v supply with ease. I also decided to use the DIP8 package version, instead of the smaller SOIC package for ease of socketing and swapping, in case the IC should become damaged. Other than that, the design is straight forward.
I ended up using the converter for a few things, one being running a LED strip out of a TV that needed to overcome a forward voltage of around 20v, and the other, as a stable 12v source from a battery pack for various networking devices in the event of a power outage. The output voltage can be set up to 40v, but the higher the output voltage, the less current is available. I’m relatively satisfied with the output, and perhaps will make a buck or inverter board at some point in the future.