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I am new to pcb design and my first designed pcb is burning, I have checked some traces and I found this: enter image description here

C18 capacitance is 0.1uF and 100V rated. The problem is that slim trace width is only 0.2mm. So maybe this might cause some burning. is there any way to fix this issue?

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    \$\begingroup\$ There is not likely to be enough current in that trace to cause a problem. Is this trace itself burning? \$\endgroup\$ – evildemonic Jul 22 '19 at 20:10
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    \$\begingroup\$ I agree. 0.1uF and 100V don't have much to do with current. Do you actually know for a fact it is too much current and not something else? Can you show us the schematic? \$\endgroup\$ – DKNguyen Jul 22 '19 at 20:12
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    \$\begingroup\$ emre - C18 seems to be decoupling between IC pin 13 and ground (pin 11). How will the traces to that component have enough current to burn - unless the capacitor is faulty? I checked and your question doesn't say exactly which trace is apparently burned. Therefore, in addition to that PCB layout image, it would help if you started by editing your question and adding the relevant part of the schematic (as others have also requested) and some photos of the damage on an actual PCB. \$\endgroup\$ – SamGibson Jul 22 '19 at 20:15
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    \$\begingroup\$ Could you please define "burn". Is there physical damage? If so please provide photo. If something is physically hot, which one \$\endgroup\$ – JonRB Jul 22 '19 at 20:54
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    \$\begingroup\$ it makes no sense to ask about increasing the width of the trace because of interference with other traces ... you should be thinking about increasing the thickness \$\endgroup\$ – jsotola Jul 22 '19 at 23:13
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With a 20C rise over ambient the vias could still support 0.9A. Which should be plenty for most microcontrollers.

The parasitic resistance of the via might pose a problem at 1.4nH and some ringing in conjunction with the caps.

The problem is if you are going over 1A, the vias might heat up. For traces over 1A the only solution would be to increase the amount of conductor.

The first thing I would do is make sure that it is the vias that are the problem, if you have a thermal camera or a temperature probe then I would take some measurements of the IC's and make sure they are not the cause of the burning.

Only the traces that carry more than 1A need to be increased.

If I were doing this with a 2-layer board, I would find a PCB drill (which can be had online for cheap). and drill out the vias that needed the extra current and solder a larger wire from the top to bottom layers.

If this were a 4-layer board I would not attempt to drill because of the potential for shorting on an inner layer. I would find a large gauge wire somewhere from 30 to 20 and solder them from the bottom to top around the outside edge of the board. This is not an elegant solution and could create noise problems

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Increasing current capability of copper trace can be done by loading with solder. However in your case i noticed that there is an airwire visible on pad11. Possibly there is an error in your pcb?

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  • \$\begingroup\$ Solder has 6x higher resistance compared to copper. Adding solder to a trace doesn't help much. \$\endgroup\$ – mkeith Jul 23 '19 at 4:18
  • \$\begingroup\$ The thickness of solder would be 4-5x of the copper trace, so it WILL help somewhat. What better solution do you suggest? \$\endgroup\$ – Kripacharya Jul 23 '19 at 11:19
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    \$\begingroup\$ Add a copper wire or strip in parallel. \$\endgroup\$ – mkeith Jul 24 '19 at 1:36

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