Another N channel enhancement mode MOSFET driven directly by a PIC12F629

[andywpg]

Well actually, The resistor should be rather small, in the order of 10 to 100 ohms Steven. When switching the gate at high frequencies you need to overcome the gate to source capacitance issue. Even at low frequencies if you take a scope and look at the gate, you will notice a delay when switching it on when using a resistor. The larger the resistor the slower the turn on time as well as discharge time. In fact when switching the gate at frequencies of approx.15+ KHz. you should be using some kind of push/pull driving circuit. In the past I have used the IR2183 mosfet driver ic's on all of my PWM full bridge drivers. They will deliver up to 1 amp to the gate. There are others available. Microchip also makes single mosfet drivers.

Hmmmm - I guess the fact that I'm just switching relatively slow stuff is the reason I haven't run into trouble with 2.2K. My engineer friend was aware of what I was building, so that's probably why he suggested the fairly large values.

And, of course there's always the possibility that I misunderstood him, and, in my ignorance, went with what I 'remembered'.

Thanks for the information!