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First, Vgs(th) is the gate-source threshold voltage at which the mosfet starts to turn on. It is not fully on at that voltage.When the mosfet is in the off-state, Vs = 0V and V(ho) pulses between 0-12V. So when V(ho) gets a pulse and rises to 12V, the voltage differential across gate en source can be calculated (47 ohm resistor + gate resistance = 1 ohm). The voltage at the gate is only 0,25V which means the mosfet will not switch.
The gate has essentially infinite resistance. Where did you find this 1Ω value?I also took notice of the gate resistance of 1 ohm.
Your need to look at the whole datasheet. Rg refers to the effective resistance that would be in series with an external gate resistor as the gate capacitance is charged. In your example, the 1 Ω is in series with the 47Ω gate resistor. If you were to calculate the maximum gate current at a certain voltage and capacitance, you might need to consider it. For the purposes of your question, I believe it can be ignored.In the mosfet datasheet.
by Duane Benson
by Duane Benson
by Jake Hertz
by Jake Hertz