Recently I picked up a few breadboard power supply boards and decided to do a review of them. You can check out the YouTube video but in short, I would recommend them but stay away from the barrel jack power source as it limits the available current that you can draw without damaging the board.
These are available from most of the China suppliers but if you aren't comfortable with buying from them, you can pick up a few on Amazon. I'll leave a link below if you are looking for some.
If interested, I spent a few minutes drawing up the schematic for you to examine.
A simple design but effective. I've also included the current calculations with the bottom 2 calculations (I@7v in, I@12v in) using the barrel jack. From that you can see that the maximum current from the breadboard power supply is 0.37A and 0.105A respectively. Given that the maximum current for the 3.3v out is 0.436A and that the other 2 are less than this means that maximum usable current for the 3.3v out is the lesser values if using the barrel jack.
For example: at 12v in, only 100ma is available, at 7v in, 370mA is available.
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