Byron A Jeff wrote :

> > >  I see that
> > > the PORTA output pins of 628A can source a max of 25mA.
> > 
> > You only need a few mA's to drive the transistor.
> 
> Right. And you do want to current limit it, so unless it's a
> MOSFET you'll want the current limiting transistor.

Now, the gate of a MOSFET (particularly the "power" ones) looks
like a fairly large capacitor to the driving curcuit, and a low ohmic
"current limiting" resistor (like limiting to 25mA in the case of
a PIC driving the MOSFET) is usualy used, not ? If the MOSFET
is used in some (high freq) PWM curcuit, there can be some
considerable power loss in the driving curcuit.

Jan-Erik.
(Was going to post this Yesterday, but my phone line went
out of service, and I've been waiting for a full 24 hours to get
it "up" again. Probably due to the heavy snowing over here the
last couple of days...)

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