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Termination of unused pairs when interfacing a I219LM to a 10/100 PHY.

idata
Employee
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When interfacing a I219LM to a 10/100 PHY, is it acceptable to leave the unused pairs as no connects, or is some manner of termination (Bob Smith?) required?

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idata
Employee
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HI etk,

 

 

Thank you for the post. Can you help clarify more what is the exact setup and configuration here? Please provide more detail.

 

 

thanks,

 

wb

 

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idata
Employee
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Hi etk,

 

 

Please feel free to provide the information.

 

 

Thanks,

 

wb

 

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idata
Employee
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Yes, I'm connecting an I219LM to a 10/100 port on another switch (Microchip KSZ8862) so I'll only need the two pairs for the 10/100, but I'm unsure of how to terminate the other (unused) 2 data pairs (since I don't intend to run them through any magnetics, since they won't ultimately be connected.) Can I just N/C them, or is there a recommended termination circuit?

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idata
Employee
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Hi etk,

 

Thank you for the reply. Just to double check are you referring you are trying to find out how to wire the cable in order to connect only at only 10/100 mbps?

 

 

Thanks,

 

wb

 

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idata
Employee
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The parts will be connected on a PCB, not through a cable, but otherwise, yes.

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idata
Employee
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Hi etk,

 

 

Thank you for the reply. Just to clarify so you are trying to connect the I219LM ethernet controller to a PCB? What is the board you are using? Are you trying to design a board? Looking forward to your reply. Thank you.

 

 

Rgds,

 

Sharon

 

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idata
Employee
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This is a new PCB design.

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idata
Employee
1,928 Views

Hi etk,

 

 

Thank you for the clarification. As this is with regards to new PCB design, it is recommended to contact our embedded design support team. You may post your inquiry at

 

https://embedded.communities.intel.com/ for them to better assist you.

 

 

Thanks,

 

Sharon

 

 

 

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