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Kevin Aylward[_5_] Kevin Aylward[_5_] is offline
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Default Tube mono-block amp with SIX 6L6 outut tubes

"Tim Williams" wrote in message ...

"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.


Exicon are the audio mosfets of choice today, apparently. They are laterals.

http://www.exicon.info/

They have the usual power limited SOA.

I don't know who actually makes them, but my guess is someone like XFAB.

Standard fab vendors will make any asic for any fabless company, even if the
asic is just the one big transistor!

-- Kevin Aylward
http://www.anasoft.co.uk - SuperSpice
http://www.kevinaylward.co.uk/ee/index.html