Capacitor used to prevent energy transfer between two circuits
This article is about the use of capacitors to filter undesired noise from power supplies. For the use of capacitors to allow AC signals to pass while blocking DC offsets, see coupling capacitor.
"Bypass capacitor" redirects here. For class-Y safety capacitors, see Line-bypass capacitor.
LM7805 5V linear voltage regulator with 2 decoupling capacitorsCapacitor packages: SMD ceramic at top left; SMD tantalum at bottom left; through-hole tantalum at top right; through-hole electrolytic at bottom right. Major scale divisions are cm.
In electronics, a decoupling capacitor is a capacitor used to decouple (i.e. prevent electrical energy from transferring to) one part of a circuit from another. Noise caused by other circuit elements is shunted through the capacitor, reducing its effect on the rest of the circuit. For higher frequencies, an alternative name is bypass capacitor as it is used to bypass the power supply or other high-impedance component of a circuit.
