The LC filter circuit composed of inductors and capacitors is one of the most common applications in circuit design. The capacitor utilizes its characteristics of blocking DC and passing AC, combined with the ability of the inductor to pass DC and blocking AC, to effectively filter out interference signals in the circuit. This combination is particularly suitable for removing AC interference signals accompanying DC power. Through the inductor, these interference signals are converted into heat energy and consumed, resulting in purer DC power. In this process, the inductor, especially for high-frequency interference signals, can effectively suppress these interferences due to its characteristic that its impedance increases with frequency.
Furthermore, as a commonly used form of inductance, chip inductors are electromagnetic induction components wound by insulated wires and have the basic functions of passing DC and blocking AC. In the circuit, chip inductors can not only isolate and filter AC signals, but can also form a resonant circuit with capacitors, resistors, etc. to achieve tuning and frequency selection. Especially in resonant circuits, chip inductors can generate magnetic fields according to changes in current, thereby affecting the current changes in the circuit. This characteristic allows the inductor to adjust current changes, reduce load current and voltage pulsations, and improve waveform smoothness. has significant effects.

As a special form of inductor, color ring inductor mainly plays a role in current blocking, tuning and frequency selection. Its hindering effect is mainly measured by the inductive reactance XL, which is directly related to the inductance L and the AC frequency f. In the circuit, the color ring inductor can effectively block the AC current. According to its parallel connection with the electrolytic capacitor, an LC tuning circuit can be formed to achieve a state where the inductive reactance and capacitive reactance of the circuit are equal but in opposite directions during resonance, thereby achieving tuning and selection. frequency purpose. This characteristic makes color ring inductors of great application value in circuit design, especially in designs that require stability and reliability.