Junction temperature of ultra fast diode of flyback smps

[treez]

Hello,
I've always limited junction temperature of such diodes to 110 deg c in the past, but is it ok if we run the MUR840 diode with Tj=150 degC?

The datasheet suggests we can. Its got 4A average in it.

MUR840 datasheet
https://www.fairchildsemi.com/datasheets/RU/RURP860.pdf

 

[KlausST]

Hi,

[QUOTEThe datasheet suggests we can. Its got 4A average in it.][/QUOTE]

Who knows better than the manufacturer's datasheet?

Klaus

 

[treez]

150degC sounds awful hot though?

 

[Velkarn]

if datasheet allow so its ok, but keep in mind this

 

[Orson Cart]

don't forget the switching losses go up with temp, leading to thermal runaway if heatsink not large or effective enough or ambient temp goes higher than expected....