traces on a pcb using a 9 volt battery?

Discussion in 'General Electronics Chat' started by AXmichigan, Aug 7, 2009.

  1. AXmichigan

    Thread Starter Member

    Jun 17, 2009
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    hey guys
    so i was working on my new project was designing my new pcb
    i was just added traces ( i am completely new to the whole pcb designing)
    and was wondering, with a 9 volt battery what size traces should i use for connecting the parts together?
    i read somewhere that i should use .050" traces for power and 0.010" otherwise for 2 amps & 0.3 amps, respectively. but i was looking up the specs on a 9v battery and it barely gives out 1amp (not to mention my circuit does not require a huge amount of current)

    what size should i use of the power traces and connecting the parts?
    thanks!
     
  2. Wendy

    Moderator

    Mar 24, 2008
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    For a 9V battery it doesn't matter. The power capacity of a 9V is so down there it rates right in with the rest of the parts. Be sure to have bypass caps for the digital chips, and your good.
     
  3. jpanhalt

    AAC Fanatic!

    Jan 18, 2008
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    If you are just starting out on making PCBs, I recommend making your traces larger than 10 mil, unless that size is actually needed for space reasons. 24 mil is plenty small for most applications. You might even consider 32 mil, as with wider traces you are less likely to run into problems in production.

    John
     
  4. AXmichigan

    Thread Starter Member

    Jun 17, 2009
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    So I should (using Express PCB) use 0.020" for normal connections, and 0.030" for power
    is that good?
     
  5. jpanhalt

    AAC Fanatic!

    Jan 18, 2008
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  6. AXmichigan

    Thread Starter Member

    Jun 17, 2009
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    great!
    thanks for the help

    i think the max current is ~200 mA = 24 mils = 0.024"
    so i was wondering
    so i will do this for the pump/power parts, should i make it less for the other parts?
     
  7. AXmichigan

    Thread Starter Member

    Jun 17, 2009
    11
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    please help!
    do i need different size traces then?
    if so, then what sizes??
     
  8. jpanhalt

    AAC Fanatic!

    Jan 18, 2008
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    You know or can calculate what sizes you need for the power traces. Make the other traces any size that suits your fancy. Thin traces have higher inductance, but judging from your other posts, that is probably not a factor in this project. The link I gave you also has some general guidelines.

    If you are making the board yourself, I would not go below 20 to 24 mil for your first attempt. However, it appears you are going to send it to a board house, so that criterion doesn't apply.

    Are you using SMD or through hole? If you have to make an alteration, say solder a jumper wire or additional component, after the board is etched, I find it easier to solder changes to wider traces (e.g., 24 mil) and keep things looking neat than to hair-thin traces.

    Some people seem to like really thin traces, maybe because they look more like some of the commercial electronic boards we see today. To me that is a non-issue.

    John

    Edit: If you go here to the Projects Collection you can see what a DIY PCB with 24 mill traces looks like. Those are all 805 SMD. Maybe my traces are wide by some standards, but they work.
     
    Last edited: Aug 7, 2009
  9. peranders

    Well-Known Member

    May 21, 2007
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    If you are going to make the board yourself use as wide traces as you can. 30-40 mils is good and if you need 20 or maybe 15 mils.
     
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