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Identify the PSE power output capability in the PD side

Hi,

Is there any way to identify the PSE power output capability in the PD side? Customer would like to know how much power can be got(13W or maybe 25W) in the PD side so they can regulate their system power output. Thank you.

Best regards.

Randy

  • Hi Randy,


    Previously, based on IEEE Ethernet identification:

    1. IEEE 802.3af Type I  : Power of PD < 13W

    2. IEEE 802.3at Type II : 13W < Power of PD < 25.5W

    I will use Type I to indicates 13W, Type II is 25W as below description.


    In PD side:

    If PSE is type 2, PD will receive a 2-event classification pulse from PSE as shown in Fig. 1.  

    And T2P pin of PD would be low as shown in Fig. 2.

    On other hand, If PSE is type 1, PD will receive a 1-event classification pulse from PSE and T2P pin of PD would be high.

    Fig.1 Detection, 2-Event Classification, and Turn on

    Fig.2 T2P Output

    In PSE side:

    PSE provides MAX. Power to PD is depend on the RCLS of PD side as shown table 1 as below.