One of the most popular articles on this website is the tutorial on how to build a 5V power supply on a breadboard. Following up on that, today we’re going to build a power supply that can output both 3.3V and 5V at the same time. This is particularly useful for circuits where both voltages are needed. We will solder the components on a small protoboard, which will conveniently plug directly into the power rails of our breadboard.
When I build a circuit on a breadboard, the first problem I always have is to create the 5V that will power the components. Of course there are a lot of pre-made power-supplies that you fit perfectly on the power rails of the breadboard, but I wanted something that I built myself and I can use with all my circuits. In this article I will present the power supply I came up with, as well as a step by step explanation of the circuit.