Re: Another N channel enhancement mode MOSFET driven directly by a PIC12F629
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.
Last edited by Dave; - 10th April 2015 at 11:46.
Dave Purola,
N8NTA
EN82fn
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