A choke inductor, also known simply as a "choke" or "inductor," is an electrical component used in electronic circuits to impede the flow of alternating current (AC) while allowing direct current (DC) to pass through relatively unimpeded. It is a type of passive electronic component that stores energy in the form of a magnetic field.
The choke inductor is typically constructed using a coil of wire wound around a core made of a magnetic material, such as iron or ferrite. The wire's coiling creates a magnetic field when current flows through it. This magnetic field opposes the change in current, which results in the inductor's opposition to AC signals, thereby acting as a filter.
The primary function of a choke inductor is to block or attenuate high-frequency AC signals, such as noise or interference, while allowing DC to pass through without significant resistance. This property makes chokes useful in various applications:
Noise filtering: Choke inductors are used in power supplies and electronic circuits to filter out high-frequency noise or ripple that might be present in the power source.
EMI/RFI suppression: Chokes are employed to reduce electromagnetic interference (EMI) and radio-frequency interference (RFI) that can interfere with the proper functioning of electronic devices.
Filtering signals: Chokes can be used in audio circuits to separate audio signals from higher-frequency interference, ensuring cleaner audio output.
Power factor correction: In power systems, choke inductors are sometimes used for power factor correction, improving the efficiency of electrical systems.
Choke inductors are passive components, meaning they do not require an external power source to function. They operate based on the principles of electromagnetic induction and are found in various electrical and electronic devices, contributing to their proper functioning and improved performance.