Bipolar PSU Proofreading

I’m seeking to create a discrete bipolar power supply for testing DIY eurorack modules. While I’m aware that this has already been covered with the Module Tester, I still find myself wanting to use a separate supply dedicated to the power side of things. Will this cover it?


Are there any caveats I can expect in regards using this for the purpose of eurorack testing?

Looking at the LM2575 datasheet, your schematic looks good. Were you able to build it? I’m interested in the power supplies.

Yeah, I’ve used this circuit to power a breadboard’s rails with great success. The difficulty, especially as a mere hobbyist, lies in assessing what amperage this circuit is capable of providing.
When using a wall wart to supply a separate supply circuit the efficacy of the power supply begins to swing about a double ended pendulum of sorts. It’s likely not the supply you’d want to use to finalize a design, but it is inexpensive and consists of relatively few parts.

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There must be some sort of golden rule for datasheets, ie. a percentage of what they claim is capable. I’d always personally stick to about 75%. Over-rating something is sensible unless you’re in the business of mass production.

I tend to err on this side of caution with the ratings of PSU components and treat 60% of the rated value as my max.

There is an old Electro Notes article on PSU design which is very useful http://electronotes.netfirms.com/PS.PDF

And also a post on the Electro-Music forum http://www.electro-music.com/forum/topic-27668-0.html&postdays=0&postorder=asc&highlight=

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Thanks for the incredible resources rumblin_cynth_rampo. Incredible.

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I just did my take on a switch-mode power supply. Ordered the boards and components, will assemble as soon as they arrive.

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Nice small PSU @smotesko! But since there are less and less modules that need +5V (and funnily at the same time more and more PSU that provide +5V), I would rather have one DC-DC converter dedicated for +12V and the second DC-DC converter for -12V. And then maybe a small third converter for +5V (some murata in 7805 compatible packaging).

Yes there’s a tendency to regulate 5V down from +12V line, while most modern PSUs provide 5V supply. I don’t understand it. But I’m designing my own modules and also will be building some kits, so I can modify the digital module kits to make them use the 5V line.

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