Re: SSTC, xfmr gate drive oddity

["Tesla list" <tesla-at-pupman-dot-com>]

Original poster: "Alan Sharp by way of Terry Fritz <twftesla-at-qwest-dot-net>" <AlanSharp-at-compuserve-dot-com>

You can make the FETs turn off faster than they turn on by putting a small
resistor say 4.7ohm in series with the gate and put a shotcky diode in //
with it so that the N channel fet gets +12v via the resistor and 0v via the
diode.

Alan Sharp (www.alansharp.co.uk)
 





Message text written by INTERNET:tesla-at-pupman-dot-com
>What I tried now was switching places of mosfets in the old compl. source
follower circuit, as shown in the CD4049 datasheet "internal schematic".
Now the p channel pulls up to 13.6V. The n channel pulls down to GND.
Common-drain connection. This did help _hugely_ to make overcome the
mosfets V_th threshold voltage problem and make the output rail-to-rail
and work like a charm waveform wise, but now there's new grief with
cross-conduction. About 20A peak during the ~50ns switching time =>
mosfets rather hot. A small series inductor would restrict this current,
but sadly the gate xfmr peak output current too => not a very usable
solution. :o(<