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| T3sl4co1l:
Yeah, running a slightly lower Vge(on) can help with that. 15V may not be necessary for operation, and 10-13V probably won't increase dissipation enough to matter. Energy in stray inductances doesn't matter, as far as dissipation. It'll amount to a few hundred nanoseconds of additional short-circuit dissipation, negligible compared to the event itself (which is already several microseconds due to intentional comparator filtering and delay). Overvoltage due to strays, can be a problem; for this reason, many gate drivers (and now we come back on topic, yay!) offer a slower turn-off under desat/fault condition. This trades peak voltage for more dissipation, and again, if we're already well under the limit, we aren't costing much reliability by holding out a few hundred nanoseconds longer. So that's basically the last option for OP to consider: slow turn-off under fault condition. Vge(on), Vge(off), Ig(pk) or equivalent driver output resistance, desat detection, and faulting turn-off, should be the full set of features to consider. (You can always do more, like use a high speed serial link to communicate timing and status; you could put an ADC up there to monitor local temperatures, sample gate or drain voltages or currents, etc., but that would be a bit over-the-top for most anything.) Tim |
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