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Tim Williams[_3_] Tim Williams[_3_] is offline
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Default Tube mono-block amp with SIX 6L6 outut tubes

"Kevin Aylward" wrote in message
...
Well... overcurrent on a mosfet output device is usually pretty safe for
quite a while. Second breakdown is the problem with bipolar. Their rating
at high voltage is much lower than their power ratings would imply.


Used to be true -- modern MOSFETs are more than current-dense enough to
exhibit 2nd breakdown. I shouldn't actually say modern, because apparently
SuperJunction process has... PTC source connections or something? I haven't
seen one without a square SOA yet I don't think. So by now, it's actually
previous generation that you have to watch out for. I forget if lower
voltage (SJ goes away under ~400V I think it was?) processes are still
prone.

Tim

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