> The fact that IR included it in the datasheet makes me think that 
> they
> have taken some care into designing the structure of the diode so 
> that
> it can substitute for the external diode normally present (for 
> example
> when using BJTs with inductive loads) in SOME cases. I don't believe
> that IR has ensured that the body diode is structured in such a way 
> that
> it should be able to substitute for ALL cases (especially highly
> inductive loads).

If the body diode is characterised in the data sheet it has probably 
been to some extent designed as well, even though it's an unavoidable 
attribute of a MOSFET. When they have avalanche energy ratings it 
means (at least that) the manufacturer has taken special care to 
spread the current evenly over all the sub transistors and to ensure 
that it doesn't get hot spotting under avalanche breakdown. Exceeding 
rated avalanche energy is a recipe for disaster. I'd guess the noted 
"part on" behaviour mentioned earlier in this thread MAY have been 
caused by some sub transistors in a die being permanently on and 
others off.


        RM 

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