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PMoha.17
Associate
Nov 21, 2018 7:46 AM UTC
Question

How to do Lightning Surge protection ?

Lightning surge protection level should meet the standard:

IEC61000-4-5

Common mode:2kV, normal mode:1kV

Malfunction:Level3

Destruction :Level 1

Mainly concerned on the PoE PD part and the Antenna part

This topic has been closed for replies.

3 replies

FGUIT
ST Employee
Nov 23, 2018 8:15 AM UTC

IEC 61000-4-5 standard specifies test setup, for unshielded symmetrical interconnection line and unshielded unsymmetrical interconnection lines.

For, unshielded symmetrical interconnection line, the surge is applied on each line in parallel, through R= (number of line)*40ohm + coupling device (C=0.5µF or GTD) on each line, and the ground.

For unshielded unsymmetrical interconnection lines, the surge is applied between lines, or line to ground, through R=40ohm + coupling device (C=0.5µF or GTD).

Test setups are shown on figures 9 to 12 of IEC 61000-4-5 standard. 

PMoha.17
PMoha.17Author
Associate
Nov 23, 2018 8:26 AM UTC

Thanks for the reply..!!

Our concern is mainly on how to take care the necessary protections on the PCB to meet the above mentioned compliance

FGUIT
ST Employee
Nov 23, 2018 4:58 PM UTC

Below list of parts suitable for POE, providing several 8/20 µs surge capabilities :

  • PEP01-5841,4 TVS bidirectionnal, Vrm=58V, Ipp 8/20 µs = 24A, 4 TVS bidirectionnal, SO-8 package
  • SMA6J58CA, Vrm=58V, Ipp 8/20 µs = 32A, 1 TVS bidirectionnal, SMA package
  • SMBJ58CA, Vrm=58V, Ipp 8/20 µs = 33A, 1 TVS bidirectionnal, SMB package
  • SMCJ58CA, Vrm=58V, Ipp 8/20 µs = 83A, 1 TVS bidirectionnal, SMC package