TPS23756EVM: BOB Smith Termination

Hi Arvind,

Thanks for reaching out. Sorry that I do not have a full IEC visibility. It is recommended to reach out to IEC for your question.

For PoE design, the Bob-Smith termination is commonly used but not mandatory used as well as other circuit can help to improve the common mode noise ruggedness.  

In White Paper 3 System Level ESD Part III: Review of IEC 61000-4-2 ESD Testing and Impact on System-Efficient ESD Design (SEED), the below description about Bob-Smith termination may help.

Best regards,

Diang