Quote:
Originally Posted by MPaulHolmes
Hi Joe! There are actually 3 pin schottkys that are compatible with the board. The mosfets are rated for 130 amps, but that isolation material is a significant limit on their ratings. Ian Hooper in Australia was saying that he was getting them to blow up at above 50 amps each.
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Schottky diodes are considerably more of a challenge to fabricate than regular silicon diodes. 200V is at the upper edge of the voltage available. Which probably means that they don't have much margin on the specs.
Compare that to regular diodes where the 200V parts might come from the same wafer as 400V parts, with the best ones being sold with the higher rating. The result is that customers often get a better part than the guaranteed minimum specs.
If the Schottky diodes are breaking down from high voltage spikes, it wouldn't take much to overheat them. Before they break down, there is little heating. (The reverse leakage current is the only a minor issue with a short-duration spike.) As soon as they breakdown, most of the spike energy ends up as heat.