I currently do not own a bench power supply at home. I could buy a decent one, with multiple channels, however none of the commercial units have the power density that I desire in the price range that I feel comfortable spending on a bench power supply. I figured I could try and build my own using my knowledge as well as resources such as open source hardware.
I should give credit to Dave Jones who designed a bench power supply, and freely distributes the schematics. See http://eevblog.com for more information. If you look at the linear stage of my design you will primarily see Dave Jones work there, as well as in other places floating around.
I have essentially designed in an Arduino Uno that does all of the controls for the channel. I primarily referenced: https://www.sparkfun.com/products/12757 for the Arduino micro.
I had the idea of adding a switching regulator to do most of the power conversion so that I could achieve much higher efficiencies on the board. This is certainly not a novel idea, and Dave actually added a switching front end to his design.
I also came up with the idea (again Im certain someone else has done this before) of putting the entire channel on a small-ish PCI card, and have plugable power supply channel modules. The current revision uses two card edge connectors to transfer power and control signals to/from the board. Right now, I am looking at a board size of ~100mm x ~75mm which is not too bad if it performs as well as I would like.
Here are some of the specifications that I hope to achieve with a single channel:
1. ~ >= 80 % efficiency overall.
2. 60W of output power.
3. 24V input
1. 0 - 20 V
2. 0 - 3 A
1. 24 V in