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How to calculate copper area for specific current

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While designing in a PCB Layout tool,I would like to calculate the copper area for specific current requirements.For example the current requirement is 160 amps and i need to draw appropriate shapes in Layout.My question is firstly how will i calculate the copper area for 160 amps and secondly how much copper thickness i need to use for that plane layer in order to have a stable system.
 

Current load capacity isn't a matter of copper area rather than trace cross section (width multiply thickness). You can easily calculate trace resistances and related resistive power dissipation.

For 160 A, I would think about at least 4 to 6 ounces copper weight (140 to 210 um thickness) or similar multilayer sandwich design. Design rules for thick copper PCB are rather restricted (minimal structure width, spacing), but it can be done.

A rule of thumb for a quick estimation. Sheet resistance of 1 oz. (35 um) copper is about 0.5 mOhm. That means a 100 mm long trace of 10 mm width has e.g. a resistance of 5 mOhm (sheet resistance * length / width). Scale with copper weight/1 oz.
 
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    Syrus

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This depends on the maximum current density specification from the PCB manufacturer.

Normally you should receive a booklet with the PCB specifications containing minimum metal width, spacing and so on. A design rule booklet.

You should find a figure of merit with units in Amps/mm2 or so.
 

Current density numbers don't help much for extreme designs. It's more reasonable to estimate copper overtemperatures based on thermal models. The cooling concept is the first point to be answered.
 

That is true. However, in some booklets, this is taken into account in the density numbers as reliability against metal migration.

Thermal models are of course very important as well.
 

Electromigration in copper is reported for currents > 10e6 A/cm², which is at least one, more likely two orders of magnitude above reasonable current densities of power PCBs. It's more a problem in IC interconnect and possibly in HDI PCBs.
 

here is a link to the ipc2152 description and excel spreadsheet (link is inside document) on how to calculate current carrying capacity.

frontdoor.biz/PCBportal/HowTo2152.pdf
 

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