I am an engineering student at Oak Ridge High and have started to learn PCB design. I just finished designing my first PCB and had several concerns about it. My main concern is that I'm not sure is the supply rails for the 5V and GND are large enough. I'm expecting at most peaks of around 15-16 amps to go through this board.

If anyone would be able to take a look at my board design before I have it made and then possibly fail that would be so helpful. Any suggestions on changes are readily welcome. This board is going to be used to drive a 8x8x8 cube of LEDs.

The board and schematic files are in the enclosed link: https://www.dropbox.com/sh/33xup0rf5dw9f36/AABldcXm4Cta2-585d3HQwXLa?dl=0

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  • \$\begingroup\$ Comments are not for extended discussion; this conversation has been moved to chat. \$\endgroup\$ Commented Nov 20, 2017 at 5:50
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    \$\begingroup\$ 15A is no joke for a first PCB design. Since its an LED cube I assume you aren't gonna make that many of those. Maybe use some improvised bus bars? (i.e. thick copper wires soldered to the traces) \$\endgroup\$
    – Wesley Lee
    Commented Nov 20, 2017 at 5:57
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    \$\begingroup\$ If you're concerned about the trace width of your rails, use a calculator to figure out your voltage drop and power loss. My recommendation, which I use at work, is the Saturn PCB toolkit saturnpcb.com/pcb_toolkit.htm . It's got some other calculators you won't need for this board, but a tool like this is indispensable if you continue on into a hardware design role. \$\endgroup\$ Commented Nov 21, 2017 at 4:15

1 Answer 1


As a recently graduated High School student, I shall formally welcome you to the club! I have a few notes:

  1. Your Vias are too small. The internal plating can be quite thin, and the current capacity is generally defined by the hole size, not the annular ring size. Rule of thumb is to have the internal hole diameter roughly the hole width.
  2. If you specify no soldermask over the two large traces, you'll be able to flood them with solder, which should give you enough bus current capacity.
  3. Your status indicator LEDs are overlapping
  4. Large SMD resistors aren't really any harder to solder than PTH.

And, I just realized the extent of the chat discussion precluding an answer, this might be duplicate.


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