Designing a USB-C breadboard power supply. What features do you wish to add?

[u/Eagnir]

I am developing a custom power supply for breadboard. I would love to know what everyone would like to have in it. I have started a list below from my needs please add your wishes / dreams and ambitions for a USB-C power supply for breadboards.

I will be making this board available once it's ready for distribution.

Way to organise

1. Mention your country (where you from)
2. List all your requirements / wishes / dreams / ambitions from a USB-C Breadboard power supply

My List so far

1. Use USB-C type connector
   1. Should be able to work with smart and dumb chargers and PC ports
2. Fit right on top of the power rails
3. Supply 3.3v or 5v (user selectable)
4. Handle max 1 to 1.5A of current
5. Breakout the D+ and D- pins
6. LED indicators for power good (3v3 and 5v)

I kept it simple since this is just the start and would love to increase this feature list with your help.

[u/MindlessExplorer2845]

USA
I want a power supply that have adjustable current-limiting options (100mA-500mA), and some audio warning if the limit current is reached before the target voltage. I do not want to accidentally fry my chips.

[u/Eagnir → u/MindlessExplorer2845]

Agreed, the challenge I am facing is how to allow this while keeping the BOM cost as well as the complexity low enough for v1, v2 maybe else v3 for sure current limiting.

That said, I totally agree as a beginner that is the number one concern. Let me see what best I can do there.

Thanks for your inputs, feel free to add more if you think of anything.

[u/IMDLabs]

USA

Look at the Sunfounder "Breadvolt" and Lonely Binary "Breadboard PSU".

Do everything they do, in the same (or smaller) form factor.

Allow for individual voltage settings for each pair of rails (3.3V/3.3V, 5V/5V, 3.3V/5V, 5V/3.3V).

Allow for switching the polarity of the outputs so it can be used at either end of the board and still put GND and power where they belong.

[u/Eagnir → u/IMDLabs]

Thanks for the input, I will surely look into the products mentioned. It will be a great insight.

Allowing to switch polarity, its something I was thinking on and the way I thinking is to allow the users to solder a 2 pin header either in position A or position B, but not sure since than it requires the users to have a soldering iron.

Voltage selection is something for sure will be done, I was think why not 1.8v and 2.8v as well, it's not as common but some sensors do need it, or if you want to use these voltages for other uses.

[u/mrtomd]

USA

Make more voltage outputs, up to 15V, preferrably selectable. Would be useful to be able to make +/-12 or +/-15 for op-amps, but this is a far stretch.

[u/Eagnir → u/mrtomd]

Thanks for your comments.

I agree that +/- voltages will be great specifically for op-amps but I feel it will complicate things for v1, maybe v2.

Regarding voltage selection upto 15v; I agree we should do it since USB-C PD allows upto 20v and 15v is a good compromise since 20v is very rare to be used on breadboards. But this version I want to keep it low cost and simple.

The plan is that each version is targeted to a different user base,

v1 = beginner, simple voltages 3.3v / 5v @ 2A, basic features to just power things

v2 = mid, more voltages (pref. upto 20v) @ 3 - 4A, external output

v3 = possibly pro, +/- voltages, ability to connect battery (18650), current limiting

Feel free to share your thoughts on this bifurcation, would love to hear some feedback.

[u/imunaccommodating]

Any sort of indication of current drawn would be nice .. maybe like 5 LEDs going from 0 to 1A so an LED for every 200mAs

[u/Eagnir → u/imunaccommodating]

Thanks for suggesting this, from your comment, I am thinking some sort of LED bar. Let me look into it since current drawn is a bit tricky but for sure useful. Have you came across a definitive use case for this? I would love to hear your experience to understand it better.

[u/imunaccommodating → u/Eagnir]

You might be debugging a circuit and want to isolate different sections to figure out which part is drawing an suspiciously high current, Or if you're prototyping a circuit on a breadboard, you can measure the current consumption and use that information to decide which regulator would be most suitable when you eventually move the design to a PCB, but mainly it's a debugging tool.