The time has come to start considering design changes for one of my more commonly shipped projects: The Breadboard PSU. It’s had a few revisions in the time I’ve been making them, most recently moving towards panelisation and automation of more of the build.
Feedback is one of the things which helps me make better things. So the point of this post is to invite people who have bought, used, or seen the PSU to give feedback about it.
At the moment, I have a few changes in the back of my head for the next revision:
- The 3.3V reg is fed directly from the input voltage. This means it really has trouble supplying much current at all (it’s very thermal limited, since it’s a linear regulator). This should be moved to be fed from the 5V side.
- The 5V regulator is now going to handle the most load and therefore leak the most heat. The SOT-223 package is not the best for thermal performance, I’d like to re-arrange it for a D-PAK version instead.
- D-PAK would also allow a more comfortable fit for a heatsink, probably a small 8x8mm one just to try to help improve thermal performance.
- The MOSFET on the input side for reverse polarity is great for low loss, but is much less critical than I originally felt. It’s slightly less area than a diode. Given the other changes, I’ll probably switch this back to a diode.
- The DC jack is large and annoying. Either needs to be SMD mount, or possibly take the plunge on JST and include a JST to DC jack cable.
Anyway, feedback is very welcome and I’m happy to answer any questions!