When it comes to electrical engineering components created to block out high-frequency noise, you cannot go wrong with common made chokes. Read on to discover what they are, precisely how these high-functioning electrical filters work in relation to power and data lines, as well as the many benefits that they promise over single wound inductance or simple chip beads.
What are common mode chokes and how do they work?
As already mentioned, common mode chokes, which are very similar to other components known as ‘current compensated chokes’, are essentially electrical filters designed to block out high-frequency noise or signal interference.
This high-frequency noise occurs from both input and output sides of the device simultaneously. Further to this, the noise also couples back to the ground. Ultimately, the goal of common mode chokes is to ‘grasp’ that excess noise and prevent it from being transmitted. In order to achieve this, it is essential to capture and ‘burn off’ the neutral and line signal currents as heat through a common device. A common mode choke is the component where both the neutral and line windings are wound around a single core. In short, the common mode choke effectively limits high-frequency noise without having any negative impact on the required signal.
What are their benefits?
While it is true that common mode chokes are somewhat costlier than chip beads (SMD ferrite) and other single wound inductance solutions, they do promise electrical engineers a host of benefits that make the extra cost worth it in the long run.
For example, common mode chokes are much more efficient than any other noise-reducing alternative. This is largely because they are capable of operating at a high current with significant inductance values. When you opt for common mode chokes, you can also benefit from their customizability, and this often means that you can select a heavier gauge wire for a higher current.
It is also important to note that in many instances when high speed signals are involved, such as USB, common mode chokes promise a strong technical advantage and are often the only realistic solution. They are capable of perfectly maintaining the transmission signal all while reducing unwanted noise.
Choosing the right common mode choke for your application
There are several different types and manufacturers of common mode chokes, so how can you know for sure that you are selecting the correct one? The most vital consideration is choosing the right cut-off frequency, but you also need to investigate other factors, like size and cost. The easiest way to do this is to consult a search engine comparison tools specifically designed to help electrical engineers source a variety of electrical components. Octopart is a great example of this type of search engine, allowing you to compare common mode chokes based on your requirements and budget constraints.
There is no denying that common mode chokes are the way to go when you need to inhibit high-frequency noise. You can feel confident in your decision to proceed and make that purchase.
