On 8/12/2011 9:45 AM, Dave Tweed wrote:
>  Another way of looking at this is that the 5K impedance of the level=20
> shifter, divided by the beta of the emitter followers, is already an=20
> effective series resistance for the MOSFET gate. -- Dave Tweed=20
So, assuming the hFE of the transistors is approximately 100, I've got=20
the equivalent of a 50 ohm resistor already in in place, which makes=20
adding 10 more ohms redundant.  That amazingly makes some sense, and=20
also explains the curves I'm seeing on the gate drive, and why adding 10=20
ohms only adds, well about 20% to the switching time.   I'll have to=20
post those curves somewhere as well.

So, assuming i understood that correctly, I guess I should skip the gate=20
resistor since it is adding cost and would tie up another feeder since=20
it isn't (yet) a standard value.

-forrest
--=20
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