The thick copper PCB consideration

Discussion in 'General Electronics Chat' started by Realwin, Oct 18, 2010.

  1. Realwin

    Thread Starter New Member

    Oct 18, 2010
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    Hi ! Everyone. Last week I ordered a 4OZ copper thickness of PCB in PCBwing.com , as a high-power drive. They told me that this requires a larger space. I think this all will help, you can pay attention to your own design.:)
     
  2. Realwin

    Thread Starter New Member

    Oct 18, 2010
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    [​IMG]
     
  3. marshallf3

    Well-Known Member

    Jul 26, 2010
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    Just because it's 4 oz copper doesn't mean it's going to carry a ton of current, you still need to do the proper calculations that we all have to regarding copper thickness.

    Simple circular mils on a PC board don't add up the way they do with common wire.
     
  4. SgtWookie

    Expert

    Jul 17, 2007
    22,182
    1,728
    Marshallf3,
    Although I'm sure you're aware of how to calculate required trace widths, have you seen PCBtrace?

    Roman Black has it hosted on his site: http://www.romanblack.com/pcbtemp.htm

    Pretty handy freeware tool.
     
  5. mcgyvr

    AAC Fanatic!

    Oct 15, 2009
    4,769
    969
    Trace spacing should be determined by the operating voltage of a product (creepage/clearance requirements). That dimension they list is simply because of the fabrication process to avoid reduced spacing issues while etching heavy copper.
     
  6. marshallf3

    Well-Known Member

    Jul 26, 2010
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    Thanks, I've seen and used a couple of different ones that are out on the web. There are still times however that I'll etch the circuit on common 1 oz and add an additional piece of bare wire acrss a trace that has to carry a lot of current such as the output legs of a power FET driver. No reason to make the whole board out of thick stuff, it's far too cost prohibitive and as mentioned during the etching process you get concave areas between the resist and the board itself. If you specify too thin of a line width half of the center area of the trace can be etched away.
     
  7. DonQ

    Active Member

    May 6, 2009
    320
    11
    And, I may be restating the obvious, but on multi-layer boards, use multiple layers for high current traces. Through-board components will make a high-current connection with all layers, but surface mount needs multiple adjacent, large(ish) vias.
     
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