Erica Synths EDU DIY Wavefolder Eurorack Module Kit - Manual (Page 45)

Capacitors C5 and C6 are additional decoupling capacitors. If you inspect the PCB, you’ll
see that these are placed as close to the power supply pins of the ICs as possible. For
well-designed, larger PCBs you will find decoupling capacitors next to each IC. Like the
others, their job is to simply compensate for any unwanted noise in the supply rails. If the
input voltage drops, then these capacitors will be able to bridge the gap to keep the voltage
at the IC stable. And vice-versa - if the voltage increases, then they’ll be able to absorb the
excess energy trying to flow through to the IC, which again keeps the voltage stable.
Typically, 0.1 uF capacitors are used for this purpose.
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