MOD-POE-V2 case and temperature

[shug]

Hi all,
I have two problems with this module (MOD-POE-V2) :
How to attached it to a case (there is no screw hole) ?
Is it normal that it is so hot ? I can't push my finger on it after a few running hours.
Any idea ?
Thank you

[soenke]

Stepping down from 36V to 5V creates some losses, the Si3402 has also a very small package and has to dissipate up to 1W. With its 44°C/W it will heat up to 59°C@25°C ambient temperature. But as long as the ambient temperature does not rise above lets say 40°C there wont be any problems with that.

If you dont have a temperature sensor to measure the temperature of the chip: @60°C you can hold your finger for about 1s on the surface. It gets immediatly really painful and after holding on for 1s you might get some burn marks.

[mocambo]

Hi all,
I'm evaluating Si3402 and I'm curious about this temperature problem.
As I see in the datasheet, Silabs recommends to bypass onchip diode bridges when output power is > 7W.
For the Olimex board, I see that RJ45 connector LAN+POE IN include the diode bridges, but you need to connect the output of the bridges to VPOSS and to VNEG, not to SP1 and SP2.
It is very interesting if this solve the problem...