SNLA466A August   2024  – October 2024 DP83822I , DP83826E , DP83826I , DP83867E , DP83867IR , DP83869HM

 

  1.   1
  2.   Abstract
  3.   Trademarks
  4. 1Abbreviation
  5. 2Introduction
  6. 3EMC Emission
    1. 3.1 Radiated Emission
      1. 3.1.1 Test Setup for Radiated Emission Test
      2. 3.1.2 Main Radiated Emission Sources
    2. 3.2 Conducted Emission
      1. 3.2.1 Test Setup for Conducted Emission Test
      2. 3.2.2 Main Conducted Emission Sources
    3. 3.3 Debug Procedure on EMC Emission
      1. 3.3.1 General Debug Procedure
      2. 3.3.2 RE Specific Debug
      3. 3.3.3 CE Specific Debug
  7. 4EMC Immunity Test
    1. 4.1 EMI Passing Criteria
    2. 4.2 Common EMI Knowledge
    3. 4.3 IEC61000 4-2 ESD
      1. 4.3.1 ESD Test Setup
      2. 4.3.2 Possible Root Cause of Failure
      3. 4.3.3 Debug Procedure
        1. 4.3.3.1 Follow the Test Setup
        2. 4.3.3.2 Remove External Factors on Cable or Link Partner
        3. 4.3.3.3 Areas to Explore to Improve ESD Performance
          1. 4.3.3.3.1 Air or Capacitive Coupling Discharge ESD Recommendations
          2. 4.3.3.3.2 Direct Contact Discharge ESD Recommendation
        4. 4.3.3.4 Schematic and Layout Recommendations
    4. 4.4 IEC 61000 4-3 RI
      1. 4.4.1 RI Test Setup
      2. 4.4.2 Possible Root Cause of Failure
      3. 4.4.3 Debug Procedure
        1. 4.4.3.1 Follow RI Test Setup
        2. 4.4.3.2 Remove External Factor on Cable or Link Partner
        3. 4.4.3.3 Found out Main Emission Area
        4. 4.4.3.4 Schematic and Layout Recommendation
    5. 4.5 IEC 61000 4-4 EFT
      1. 4.5.1 EFT Test Setup
      2. 4.5.2 Possible Root Cause of Failure
      3. 4.5.3 Debug Procedure
        1. 4.5.3.1 Follow EFT Test Setup
        2. 4.5.3.2 Remove External Factor on Cable or Link Parnter
        3. 4.5.3.3 Areas to Explore to Improve EFT Performance
        4. 4.5.3.4 Schematic and Layout Recommendation
    6. 4.6 IEC 61000 4-5 Surge
      1. 4.6.1 Surge Test Setup
      2. 4.6.2 Possible Root Cause of Failure
      3. 4.6.3 Debug Procedure
        1. 4.6.3.1 Follow Surge Test Setup
        2. 4.6.3.2 Remove External Factor on Cable or Link Partner
        3. 4.6.3.3 Area to Explore to Improve Surge Performance
        4. 4.6.3.4 Schematic and Layout Recommendation
    7. 4.7 IEC 61000 4-6 CI
      1. 4.7.1 CI Test Setup
      2. 4.7.2 Possible Root Cause of Failure
      3. 4.7.3 Debug Procedure
        1. 4.7.3.1 Follow CI Test Setup
        2. 4.7.3.2 Remove External Factors on Cable or Link Partner
        3. 4.7.3.3 Areas to Explore to Improve CI Performance
        4. 4.7.3.4 Schematic and Layout Recommendation
  8. 5Schematic and Layout Recommendation for All EMC, EMI Tests
    1. 5.1 Schematic Recommendation
    2. 5.2 Layout Recommendation
  9. 6Summary
  10. 7References
  11. 8Revision History

4.3 IEC61000 4-2 ESD

IEC61000-4-2 tests the device's immunity to electrostatic discharge (ESD). This test simulates the effect of electrostatic discharge in direct or near contact with electronic equipment. There are three different ways of performing this ESD test:

  • Direct contact discharge
  • Air contact discharge
  • Capacitive coupling discharge

Direct contact discharge test uses an ESD generator tip in contact with the system. In most industrial applications, the RJ45 or connector shield is exposed to the surrounding system. As the user is likely to touch this shield and introduce ESD noise in the system, direct contact ESD tests are often performed directly on the connector shield. However, specific applications require a direct injection on the protocol conducted shield exposed to the surroundings. The standard does not define the specific point of injection for ESD testing. Therefore, the point of injection can vary with each application.

Air contact discharge is an indirect coupling discharge to the system. The round tip of the ESD gun acts as an antenna source, with the noise coupling through air to the system. The noise source from air can couple anywhere to the system. Therefore, this test is normally done near the PHY.

Capacitive coupling discharge is another indirect coupling discharge to the system, with the ESD noise injected on the metal plane around the system. In this test, the metal plate acts as an antenna coupling noise into the system directly. Capacitive coupling discharge tests require the system's orientation to rotate for the ESD test.

ESD test level:

  • Level 4: ± 8kV (contact discharge), ±12KV (capacitive coupling), ±15kV (air discharge)
  • Level 3: ± 6kV (contact discharge), ±8kV (capacitive coupling), ±12kV (air discharge)
  • Level 2: ± 4kV (contact discharge), ±6kV (capacitive coupling), ±8kV (air discharge)
  • Level 1: ± 2kV (contact discharge), ±4kV (capacitive coupling), ±6kV (air discharge)

Note: Class A, Class B, and Class C performance depends on system requirements

ESD injection waveform:

ESD testing is the process of injecting a high voltage signal (kV) with nano-second pulse width. This is repeated 10 times, with a one second interval between each ESD strike.

ESD test waveform Figure 4-2 ESD test waveform