Schottky Diodes

[ed181]

Does anyone know about the reverse breakdown voltage of schottky diodes and how it vaires with temperature. I've done some research and found that the reverse breakdown voltage stated in the data sheet only applies for room temperature and that it should not be used for diodes operating at above this temperature. I guess my question is if i have a diode in a circuit at 60 degrees with a maximum inverse voltage of 50V being applied what would be a safe reverse breakdown voltage for the diode? Is 200V enough to ensure no failures?

thanks in advance

 

[shrtrnd]

Try to find a data sheet (usually the best source is the original manufacturer), and
get a graph with the temperature characteristic curve of the particular device.

 

[(*steve*)]

You'll find that the reverse breakdown of schottky diodes is quite soft. They'll leak a surprisingly large amount of current in the reverse direction when the junction is at elevated temperatures.

I pointed one out a couple of days ago that would leak *HALF AN AMP* at one end of it's specified range. At this point it was not considered (surprisingly) NOT to have reached the reverse breakdown voltage!

 

[ed181]

Hey,

Thanks for your replies, i think i know what im doing now. Turns out the diode i that was being used in the circuit i was making had a very high max reverse leakage current and was carefully hidden by a graph displaying typical values. Hence the low failure rate. The new diode i'm using should be much better!

cheers