In "real" circuits, too small an Rgate increases losses due to
switching times being too fast. You wish :-).

Most transistors have a pulse current rating well in excess of
Icontinuous_max and can stand drive current peaks in excess of their
avrage ratings.

I consider that gate-source reverse zener at FET is a near necessity -
especially if enthusiastic inductive loads exist. I always use a zener
here.

You may need one zener across R1 and a second one at FET as above with
slightly greater voltage than one across R1. Done wrong driver will
fight gate zener. Gate zener alone makes it likely that driver will
fight gate zener. Across r1 alone provides little protection against
Miller effect couplings to gate -  more so if Rgate is non-zero.

Alternative is zener across R1 and small reverse Schottky physically
at FET. This does NOT prevent Vgate rising too high but prevents
parasitic oscillations that may cause problems.


Russell
--=20
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