See attached schematic. Using the PD only to identify capability of PSE (802.3af, at or bt) and to put a slight load (the 5k Ohm). I want to completely disable the PD either by using the switch on the ground side or pulling pin 5 (Aux) high using an MCU. The Q3 transistor is to protect the switch from a possible arc only.
My issue is the PD is not properly negotiating a connection. The PSE indicates “Too Low” a resistance of 13Kohm. I understand the schematic is not a standard setup, but do you see a fatal flaw that could cause the Rdet to be too low? Vadp is connected to Vdd to allow the Aux pin to enable and disable the PD. Could that be what is causing this?
Yes, I meant the whole device. This is to remove the CLS and load (R30) resistors.
I ended up connecting the Vadp to another supply of (12v) on the board that is powered on after PoE negotiation is over. After doing that I was able to disable the PD using the AUX pin. So I should be good to go. thank you.
