I've come across this schematic from an RF device where I've spotted some weird configuration of capacitors. There are, all around the schematic, some shorted capacitors which I can't figure out what are for.

You can see, for example, in the images below, that C306, C307 and C308 are shorted.

Any clue of what are they for?




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    \$\begingroup\$ For very high frequency, a short piece of wire or a short PCB trace is an inductance. So the "shorted capacitor" is a LC resonant circuit. \$\endgroup\$ – Uwe Mar 8 at 11:25
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    \$\begingroup\$ Why don't you show the associated layout for these components? Its not clear what layer this is in pink... \$\endgroup\$ – Sean Houlihane Mar 8 at 12:47
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    \$\begingroup\$ Possible duplicate of Why does Samsung include useless capacitors? \$\endgroup\$ – SamGibson Mar 8 at 13:07
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    \$\begingroup\$ Those are high-current paths (C306, C307, C308) for RF, and low-impedance - doesn't take much inductance to resonate them, as @Uwe suggests. They could be "tweaks" to improve harmonic rejection, or to improve balance. \$\endgroup\$ – glen_geek Mar 8 at 19:23
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    \$\begingroup\$ Except the samsung question was not connected to two different planes, this one is. The other question was not about schematics this one is \$\endgroup\$ – Voltage Spike Mar 12 at 1:49

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