Hi,
I have a board with DP83848I that we have made that appears to be getting hotter than expected. The board is powered off POE power with a LM5166YDRCR 3.3v regulator. this powers the MCU without any issues and appears to be very stable running a STM32F407VET without the MCU getting warm. The network connectivity works and functions as it should except the PHY is getting hot. When we run the board from a usb to Serial board with a 3.3v feed it appears to run a lot cooler over this than the POE. But it sill appears to be warmer than expected. I have a Dev board with the same MCU and PHY and the PHY does not get warm at all on Serial power. It would be appreciated if someone could provide some feedback on what maybe causeing the PHY to get hot.