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We were using switching regulator and when we turned on the regulator short was found.

C285 was damaged. After removing C285 , regulator worked without any issues. We were suspecting inrush current due to capacitor placed before inductor. Can there be some other reason for this issue? eSchematic

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  • \$\begingroup\$ It's not clear what kind of switching regulator you're using and where specifically it sits: give is a more complete schematic. Chances are you really should not be putting a capacitor where you put it, but it's impossible to say for sure using your incomplete schematic. \$\endgroup\$
    – mmmm
    Commented Jul 26, 2021 at 7:08
  • \$\begingroup\$ Please zoom out a bit. Which regulator chip is that? But it does look a bit suspicious, I just want to confirm it is wrong or not. \$\endgroup\$
    – Justme
    Commented Jul 26, 2021 at 7:08

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Your SWH1.. are switching outputs of your regulator; you really must not put the capacitor where you put it:

Instead of rapidly switching the current through the inductor, you'd guarantee the current change is always limited by the capacitor. That is the literal opposite of what you want in a switch mode supply!

Of course this means you'd have a very very high AC component through the capacitor, with the potential for damaging it.

You probably wanted to put the capacitor on the other side of the inductor? Consult your regulator's data sheet for reference circuits.

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