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What is the significance of these floating capacitors in this schematic ? This schematic is created by Great Scott and is available here, http://www.instructables.com/id/DIY-Wireless-Energy-Transfer-System/

  • 3
    \$\begingroup\$ They are not floating. They are connected between 12V and GND, and are supposed to be physically close to the components they are drawn next to. \$\endgroup\$
    – Eugene Sh.
    Mar 5, 2018 at 15:16
  • \$\begingroup\$ Seems like a pretty poorly drawn schematic. There is no reason to not connect the capacitors to the appropriate terminals with a wire, and then connect that wire to a net. \$\endgroup\$
    – Joren Vaes
    Mar 5, 2018 at 17:17
  • \$\begingroup\$ Those are "smack me" requests. If you give a diagram like that to work from, I'm gonna smack you for scattering the decoupling capacitors all over like that instead of putting them some place that shows what they are supposed to be decoupling. And, there aren't enough of them. If they were where they belong, you'd be more likely to notice that the ICs don't all have dedicated decoupling capacitors. \$\endgroup\$
    – JRE
    Mar 5, 2018 at 18:12
  • \$\begingroup\$ Hmmm.. really? It's not uncommon drawing that way just for clarity. Indeed, it is even common to lump all the decoups on their own page and leave the details to the PCB designer. Placing them looking like they are wired to a particular chip does not translate to where they end up unless the PCB designer uses the schematic as a reference, which is not guaranteed. \$\endgroup\$
    – Trevor_G
    Mar 5, 2018 at 18:23
  • \$\begingroup\$ @Trevor_G I worked with PCB designers that are pretty much clueless about the electronics considerations. Oh yes, they knew the manufacturing process and how to route stuff nicely. But this type of things had to have some clear instructions given as a separate document or clearly stated on the schematic. Well, sometimes given by phone. \$\endgroup\$
    – Eugene Sh.
    Mar 5, 2018 at 18:31

1 Answer 1


Those are bulk storage and decoupling capacitors. They are often shown like that with no particular association with a particular part of placement though proximity on the drawing gives the PCB designer a clue.

In fact though, the schematic is missing some decoupling for the devices.

  • \$\begingroup\$ @EugeneSh. yup, probably. A lack of 5V decouplers though. \$\endgroup\$
    – Trevor_G
    Mar 5, 2018 at 15:18
  • \$\begingroup\$ Yeah, I missed a word in your answer, sorry \$\endgroup\$
    – Eugene Sh.
    Mar 5, 2018 at 15:19

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