Common Mode Choke – ET24
ET24 line filter choke is very unique and potent tool in suppressing electromagnetic interference (EMI). It is one type of Common Mode Choke that fits into input filter section of power handling circuit.
To know how to use this device, it’s essential to understand the phenomenon it is designed to mitigate – common mode noise. Common mode noise occurs when unwanted electrical noise is present in both the signal and ground lines of a system, leading to interference and potential malfunctions. This noise can stem from various sources, including power lines, radio frequency signals, and electronic components themselves. ET24 common mode choke is constructed using two coils wound on a plastic bobbin fitted within rectangular ferrite core. These coils are wound in such a way that they create a magnetic field that interacts with the electrical currents passing through the wires. The key principle here is the differential mode inductance – the choke allows normal differential mode signals (the intended signals) to pass through unimpeded, while actively blocking or attenuating common mode noise.
- Protection from External Interference: It shields electronic devices from external sources of interference. For instance, in audio systems, they can help prevent radio frequency interference (RFI) from affecting audio quality.
- EMI Suppression: By effectively impeding the propagation of common mode noise, these chokes enhance the quality of signals, ensuring that electronic devices can operate without disruption.
- Power Line Conditioning: They prevent unwanted noise from affecting the power lines, leading to cleaner and more stable power delivery. This is particularly crucial in sensitive equipment like audio amplifiers, where even small amounts of noise can result in audible distortions.
- Radiated Emission Reduction: Unchecked common mode noise can lead to radiated emissions, causing problems such as failing electromagnetic compatibility (EMC) tests. By suppressing this noise at its source, common mode chokes aid in meeting EMC requirements and regulations.
- Data Communication: Common mode chokes help prevent signal degradation and data loss by minimizing the impact of common mode noise on the communication lines.
The compact form factor of ET24 and similar other ET series devices make them popular choice among design engineers. These components are often used in high end audio circuits, control electronics, communication devices, test equipments, high frequency circuits etc. It contributes to smoother operation, improved signal quality, and compliance with regulatory standards.