What is the main purpose of capacitive coupling?

The primary purpose of capacitive coupling is to facilitate the passage of alternating current (AC) signals while effectively blocking direct current (DC) components. This is achieved through the unique properties of capacitors, which allow AC signals to traverse the capacitor due to their continuous changing voltage, while DC signals, which maintain a steady voltage over time, do not cause current to flow through the capacitor.

In circuits, capacitive coupling is often utilized in situations where it is essential to isolate different parts of the system while still allowing the AC signal to pass from one stage to another. This is commonly seen in audio amplifiers and radio frequency applications, where the amplification of AC signals is needed without impacting any DC levels that may be present in the source or the load.

This characteristic makes capacitive coupling crucial for maintaining signal integrity in various electronic applications, ensuring that AC signals can be processed without interference from DC components.