SLVAFU8 July   2024 TPSI2072-Q1 , TPSI2140-Q1 , TPSI3050 , TPSI3050-Q1 , TPSI3052 , TPSI3052-Q1 , TPSI3100 , TPSI3100-Q1

 

  1.   1
  2.   Abstract
  3.   Trademarks
  4. 1Introduction
  5. 2What Are Solid-State Relays?
    1. 2.1 History
      1. 2.1.1 Electromechanical Relays
      2. 2.1.2 Solid-State Relays
    2. 2.2 Isolation Technologies
      1. 2.2.1 Isolation Specifications
    3. 2.3 Relay Evolution
  6. 3Failure Mechanisms
    1. 3.1 Arcing in an Electromechanical Relay
    2. 3.2 Photo-degradation in Photo Relays
    3. 3.3 Partial Discharge
    4. 3.4 Time-Dependent Dielectric Breakdown in Capacitive and Inductive Isolation
  7. 4Electromechanical vs. Photo vs. Capacitive or Inductive
    1. 4.1 Electromechanical Relays
      1. 4.1.1 Advantages
        1. 4.1.1.1 No Leakage Current
      2. 4.1.2 Limitations
        1. 4.1.2.1 Switching Speed
        2. 4.1.2.2 Package Size
    2. 4.2 Photo or Optical Relays
      1. 4.2.1 Advantages
        1. 4.2.1.1 Lower EMI
      2. 4.2.2 Limitations
        1. 4.2.2.1 Limited Temperature Range
    3. 4.3 Capacitive or Inductive Based Relays
      1. 4.3.1 Advantages
        1. 4.3.1.1 Auxiliary Power
        2. 4.3.1.2 Bidirectional Communication
      2. 4.3.2 Limitations
        1. 4.3.2.1 EMI
    4. 4.4 Overall Comparison
  8. 5Summary
  9. 6References

4.3.2.1 EMI

When sending power across a capacitive or inductive isolation barrier, switching modulation is required. These high frequency switching signals can couple through the board, which can result in higher EMI. In light of this, these newer technologies are designed with electromagnetic compatibility (EMC) to help minimize conducted and radiated emissions. These improved designs are able to meet rigorous automotive standards, such as CISPR 25 Class 5, or CISPR 32 for industrial applications.

There are additional system level techniques that designers can use to improve EMI performance. To learn more about low cost EMI mitigation techniques, please reference the TPSI2140-Q1 data sheet.