This thread has been locked.

If you have a related question, please click the "Ask a related question" button in the top right corner. The newly created question will be automatically linked to this question.

TPS2372: TPS2372-4RGWR Single Powered Device with two POE++

Part Number: TPS2372

Tool/software:

Hi TI Team,

I would like to know about the below query.

In our design we have two POE++ supported 10GBase-T RJ45 Ports. But we will be using only one port at a time to power our device(maximum power up to 70W) from an external ethernet switch.

My doubt is whether for the above case, can we use a single Powered device (TPS2372-4RGWR) to connect with two POE++-supported RJ45 ports.

If yes what are the things we have to ensure while designing the circuit and layout 

  • Hi Mari,

    Thanks for reaching out.

    For the two RJ45 ports, they only have the below two conditions and no overlap conditions for both data and PoE?

    #1 Port1: Data+PoE, Port2: Not connected

    #2 Port1: Not connected, Port2: Data+PoE  

    If so, I would think you can directly short pin 1-8 together for two ports. The not connected port could be considered as open circuit. Though some terminals' LED indicators may still be on even this port is not connected. 

    Best regards,

    Diang

  • Hi Diang ,

    Thanks for the suggestion,

    Our query is we will be using two RJ45 connectors with magnetics to support Data+PoE.

    But our use case will be:

    1.  Port 1 as Data+PoE  & Port 2  as Data alone

    2. Port 1 as Data +PoE & Port 2 as Data+PoE

    For the above use case can we connect both the RJ45 power pins together so that it will be connected to the single-powered device(TPS2372-4RGW).

    Schematic reference,In this picture only RJ45 magnetics was shown, In our case can we connect two RJ45 magnetics power pins to a single PD?

  • Hi Mari,

    Thank you for your reply.

    If the case is one port with PoE+Data and another port is Data, it is better to have them connected after passing the rectifier. Then the PHY should not be comprised by the 37 - 57 V PoE voltage. 

    I do not see an issue on the PoE side, while it is recommended to double check with the PHY team if there is a concern. 

    Best regards,

    Diang