Decoupling capacitor

1. What is the purpose of a decoupling capacitor?
2. Does every IC need a decoupling capacitor?
3. What type of capacitor to use for decoupling?
4. What is coupling and decoupling capacitor?

What is the purpose of a decoupling capacitor?

Decoupling capacitors are used to filter out voltage spikes and pass through only the DC component of the signal. The idea is to use a capacitor in such a way that it shunts, or absorbs the noise making the DC signal as smooth as possible.

Does every IC need a decoupling capacitor?

To follow good engineering practice, always add at least one decoupling capacitor to every IC. Usually 0.1µF is a good choice, or even add some 1µF or 10µF caps. They're a cheap addition, and they help make sure the chip isn't subjected to big dips or spikes in voltage.

What type of capacitor to use for decoupling?

The types of capacitors that are commonly used for decoupling applications include ceramic, tantalum, and aluminium electrolytic capacitors. The performance and cost of ceramic capacitors make them a popular option for decoupling applications.

What is coupling and decoupling capacitor?

In summary, decoupling or bypass capacitor allows DC to pass through while blocking AC, while a coupling capacitor allows AC to pass while blocking DC. A decoupling or bypass capacitor is placed in parallel with the source and the load while a coupling capacitor is placed in series with the load.