what is decoupling capacitor, why decaps needed, where is it to be placed

Question

Accepted Answer

Decoupling capacitor is used to stabilize voltage supply by filtering out noise and providing a local energy reserve for integrated circuits.

Decoupling capacitors are placed close to the power pins of integrated circuits to filter out noise and stabilize the voltage supply.
They provide a local energy reserve for the ICs to prevent voltage drops during sudden current spikes.
Decoupling capacitors are essential for high-speed digital circuits to maintain signal integrity and prevent electromagnetic interference.
Common types of decoupling capacitors include ceramic capacitors and tantalum capacitors.

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