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Old 04-01-2014, 02:15 PM   #6376 (permalink)
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The nice thing is, we can choose any frequency from 0 to like 16kHz (without spread spectrum switching), but 16KHz would probably produce too much heat under high power situations. Damien could probably comment on how the 8KHz sounds when it's in the engine compartment. I think he uses 8KHz with his IGBTs. I just downloaded 10KHz, and that seemed significantly "quieter". It's all just a trade off. Higher switching frequency = more heat. There's really no downside to spread spectrum switching, other than the annoyance of a little extra time of writing code for software PWM. Maybe I should do that. Oh heck, let's try it all!
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