Narcís Nadal

MCF52259 overheated

Discussion created by Narcís Nadal on Jun 16, 2011
Latest reply on Sep 24, 2013 by Pablo Baena

Hi all,

In my company we make a board based on the evaluation board MCF52259EVB except in the series resitor pack for the data and address bus. The ethernet chip was the same. The board runs very well but too hot (40-50ºC).

The voltage levels are very good 3.2V-3.3V


Our firmware does not use ethernet, but it remains connected in the bus lines. There is not any output device connected to the cpu.

If I loaded our firmware in the evaluation board, it runs cooler than our board (35ºC).

If I loaded an example firmware with ethernet, ir runs hotter in our board (42ºC).

Without ethernet is also the same.

Without the BDM the board runs hot too


If I stopped the firmware with the BDM it seems to be much cooler.

If I program the flash the cpu remains at 25ºC.


How can I evaluate if Is it usual in the MCF52259 or there is a hardware problem If I do not have the evaluation board (was returned monts ago)?


Thanks in advance


Narcis Nadal