Power transistors typically have thermal impedance graphs listed in their data sheets. I'm not too sure how to use these graphs yet, but supposedly you can determine the pulsed power limitations of the device from it. Has to do in part with thermal mass of the part and heatup / cool off times I'll bet. If anyone can lead me to a easy to understand application note on the subject I'd be deeply appreciative.
Anyway, this information does not exist for small signal SOT-23 dual diode packages. I've searched data sheets from 4 different manufactures of devices like the BAV99 and BAT54. They just don't offer this type of thing. I guess these devices weren't meant for heavy duty operation so this data was not included. I'm not using them to that capacity in my design. However, they will see the occasional transient and I'd like to know if I am covered.
Will most devices have similar peak pulse power ratings given similar physical size? I realize some have different electrical characteristics but is that a contributing factor? or, is it merely due to the thermal transfer capabilities of the package and size of the die?
Thanks,
Ge0rge