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Re: More SSTC Questions



Original poster: "by way of Terry Fritz <twftesla-at-qwest-dot-net>" <Fucian-at-aol-dot-com>

In a message dated 12/27/01 10:33:52 PM Eastern Standard Time, 
tesla-at-pupman-dot-com writes:

<< Hi Matt,
           Some speculation on my part and I don't have time to cover 
 old ground (posting a url relevant to the current query would be a 
 big help ;) but have you disabled the parasitic drain-source diode in 
 the MOSFETs? Are the MOSFETS getting hot prior to dying? I take it 
 drain source voltages are OK (little or no deadtime). What is the 
 mode of failure (guess = drain-source short circuit)? The 555 may 
 simply be taking a hit via the gate circuit when the MOSFET dies. The 
 gate drive transformer is a fairly universal way of feeding 
 controlled signals to the gates and coupling the gates tightly 
 together (sort of an exclusive OR function). Sorry to hear about your 
 troubles.
 
 Regards,
 Malcolm
 
   >>
Most Die HOT.Others die cold.I will be getting about 2 in streamers at 40 
volts and then begin to slowly increase voltage and them ....POP.... no smoke 
or anything.Just no output.Ill test the MOSFET and its cold and dead.Really 
weird.

Matt