SNLA466A August 2024 – October 2024 DP83822I , DP83826E , DP83826I , DP83867E , DP83867IR , DP83869HM
EMC Immunity test, also known as Electromagnetic Interference (EMI), is a test standard defining the tolerance of the device to disturbance in electrical circuits caused by external sources. EMI can cause packet interrupts, degradation, or even link loss in the system due to surrounding interference. To verify electronic devices are protected against external noise sources in real time applications, meeting EMI testing requirements is typically required before device production.
EMI can cause by both humans made and natural source including cellar network, lighting, radio environment, etc… One of the common humans made examples is ESD noise generate by humans contact with the device cause a potential disturbance on the electrical device. An example of a natural source is cell phones; calls can potentially interfere with sensitive equipment on the plane. In Industrial applications, most electronic devices are directly exposed to the environment. As a result, higher standards of EMI testing are required in non-enclosed architectures.
The EMI test standard is mainly defined by IEC61000 4-X. IEC61000-4-X is used to test system-level immunity. Many system designs are specified to comply with one or more of the tests listed within the IEC 61000-4-X specification. The below sections cover the five most common tests for Ethernet applications: