In any electronic device, it is critical to limit the electromagnetic interference (EMI) or noise within the device. This type of EMI suppression can be done through the use of EMI filters and also specific shields and actual designs of the electronic device itself.
The use of EMI suppression filters will address the electromagnetic noise that is found when an electrical current passes through wiring in the circuitry of the device. Shields can be used actually to block the EMI, and usually both are found within devices to provide the best possible suppression and elimination of the problems that occur when electromagnetic noise is present.
Why EMI Suppression is Essential
When you think of the number of electronic devices we use in the same proximity to each other it is easy to see why suppression is essential. A cell phone that is exposed to even low levels of EMI will not be able to receive incoming calls, or will disconnect or have extremely poor reception and transmission.
In the early days of the use of both computers and cell phones both these devices could interfere with each other, and other electronic systems, limiting the ability of either to receive or transmit any data. Also, EMI from other sources can impact any digital circuits on any device including switches, radio transmitters or any radio controlled devices.
Types of Electromagnetic Noise
Since any device running electricity through wiring will create some level of electromagnetic noise, knowing what devices need to have EMI suppression and which don’t is important. There are specific requirements on what type of circuits and systems need these EMI suppression filters built in to allow safe use of other devices.
In essence, any electromagnetic noise that can cause harm and is an artificial or man-made type of noise will require EMI suppression. High-frequency devices, harmonic emissions and emissions from switching power supplies all need to have the safeguards in place.
Through the use of EMI suppression filters, the noise produced in the circuitry can be filtered or shielded at different locations. It can occur on both the emission side, typically in the form of a filter, as well as in other devices in the form of a shield. There is a difference between the two as the filters eliminate the electromagnetic noise while a shield is just a block, and both are often essential for protection.
To learn more about EMI suppression filters and shields, visit Premier Magnetics online at www.premiermag.com. We offer a range of innovations in technology for all applications when EMI is a concern.
