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Re: Driver schematic
Greetings,
I've been going over Rob's schematic, with a view to
either building as in or pinching ideas, to incorporate
in a homebrew design (wanton fet vapourization in
the name of creativity :).
As always I have lots of questions and few ideas.
Snubbers
Robs circuit includes no snubbers at all - instead
relying on the diodes to deal with back emf.
I am inclined to include a little snubbing to help
with the switching losses and help with any
transients - say 330ohm and 220pf across each
pair of FETs.
Can I buffer the 3825's output with a 4427 (the non
inverting driver) or even use a pair of 4422. Opening
the way to driving more Fets or even a full bridge?
Current mode
I am simply altering the pulse width at the moment
- is there a real advantage to using current mode
(particularly if we end up using it turned full on?
FET driving
I was going to use one pulse transformer for
each out put.
ie
output--sch diodes to rails---0000000----||-----ground
Fet source-----00000000---///////------Fet gate
Fet source----->1-----------------------Fetgate
(12v zener). (10ohm gate resistor)
Is there an advantage to Rob's arrangent?
Output transformers.
My homebrew transformers worked with my 200kHz
coil. But the new one - (with more primary turns)
won't work with the 100kHz coil - because of
internal arcing - is there a reason why I could get
away with it before but not now?
Have fun everybody.
Alan Sharp (UK)