Texas Instruments released a white paper to help Power-Over-Ethernet (PoE) System designers prevent damage to their PoE powered devices from external unwanted voltage sources. Common and differential mode examples of induced voltages are discussed. The application note discusses ESD (electrostatic discharge), EFT (electrical fast transient), electrical surge transients, transients protection circuits, and Circuit Protection Solutions for Power-Over-Ethernet PoE devices.

Abstract of “Electrical Transient Immunity for Power-Over-Ethernet (PoE) System”

Electrical overstresses can cause failure, permanent degradation, or emporary erratic behavior of electronic devices or systems. The trend to reduce circuit geometries for communication systems and applications results in an increasing sensitivity to such electrical transients. The suppression of these transients can be a challenge to designers because the origin and severity of the overvoltage may be unknown.

To assist designers in coping with these issues, this application report defines simple design rules that can adequately protect the sensitive electronic parts of the system with cost-effective solutions.

Link to download the .pdf file of “Electrical Transient Immunity for Power-Over-Ethernet (PoE) System”: http://www.poweroverethernet.com/associated/files/file_515_1158142956.pdf