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If capacitors are just two conductive components sandwiching an insulator, then why aren't all PC board, or at least their traces, considered capacitors?

Soviero
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    See [Parasitic Capacitance](http://en.wikipedia.org/wiki/Parasitic_capacitance) (Wikipedia). Also related questions: http://electronics.stackexchange.com/q/56574/2028, http://electronics.stackexchange.com/q/98372/2028 – JYelton Feb 05 '14 at 04:24
  • who said PCBs weren't like caps? they simply exhibit a very low non-uniform capacitances – hassan789 Feb 05 '14 at 04:29

1 Answers1

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They are, but only noticeable in very high frequencies (microwave wavelength or GHz).

CAGT
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  • That depends on applications, some smaller frequency circuits, in boards that have high length traces should consider the capacitance of the traces. – Diego C Nascimento Feb 05 '14 at 04:04
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    If by very high frequencies you mean a few hundred kilohertz. High Trace/Bus capacitance can cause issues in even low speed 100khz i2c for example. – Passerby Feb 05 '14 at 04:32
  • On a multi-layer board, I think internal power and ground planes can have useful values of capacitance. – Peter Bennett Feb 05 '14 at 07:17