SLVAE50A February   2019  – April 2022 ESDS302 , ESDS312 , ESDS314

 

  1.   Trademarks
  2. 1Introduction
  3. 2Ethernet Protocol
    1. 2.1 Physical Layer
    2. 2.2 Isolating Transformer
  4. 3Surge Pulse On Transformer
    1. 3.1 Surge Protection Diode on Secondary Side of Transformer
  5. 4Conclusion
  6. 5Revision History

4 Conclusion

Ethernet is widely used in a bevy of industrial end equipments. The Ethernet protocol consists of a transformer that is suppose to isolate the outside world and the Ethernet controller. However due to the parasitic nature of real transformers, there is not true isolation between the primary side and secondary side. This causes issues when the Ethernet physical layer is exposed to a surge event as the pulse couples through the parasitic capacitance and can damage the controller on the secondary side. Therefore it is necessary to provide protection on the secondary side of the transformer that can handle the large currents produced. TI's ESDS3XX devices have high surge current rating that allow them to dissipate this energy and protect the Ethernet controller.