Normal Opperation temperature , WIZ830MJ Module

Dear all ,
I use this chip with the WIZ830MJ Module.
The power supply is 3,3 V.

After first connection and powering test,
the chip gets relatively warm even if it is “just powered”
What does “relatively warm” mean ?
I don’t have something to measure but the surface of the controllers feels warm when I am touch it.

My STM32F4 controller always feels “cool”.

I am sorry for the precise description “warm” and “cool” .
But I am wondering what’s happening inside the controller if is just connected to the µC without any program inside the µC running.


Hi, mruppath.

W5300 consists of Ethernet PHY, MAC, TCP/IP logic.
Ethernet PHY make warm about 50 degree. This temperature is normal. Don’t worry about that.
When Ethernet PHY is power up, even if nothing operated by MCU, Ethernet PHY is always run in order to Link detection as SPEED, Half/Fullduplex, and Reception any packet.
W5300’s PHY is more heat than other PHYs, But it is no effect on normal operation.

Thank you.