(Not looking at a schematic and assuming I know what resistor you're talking about...)
The MOSFET gate resistor damps resonance between the parasitic gate capacitance and source inductance of the FET. It's a standard component related to FETs in any application. 10-20 ohms is a typical minimum and in high speed switching, you need the minimum. Some FETs may need more than 10 ohms though. Without the resistor the FET will typically transition on and off many times when asked to transition once, greatly reducing the effectiveness of the circuit and greatly increasing the switching loss in the transistor.
If you want to protect the IC's gate driving pin from the discharging FET gate pulling it below ground voltage, you'd do that with a reverse biased schottky from the pin to ground, as close to the pin as possible. You can also have one to clamp the pin to no more than Vcc although that tends to be less of an issue.
The MOSFET gate resistor damps resonance between the parasitic gate capacitance and source inductance of the FET. It's a standard component related to FETs in any application. 10-20 ohms is a typical minimum and in high speed switching, you need the minimum. Some FETs may need more than 10 ohms though. Without the resistor the FET will typically transition on and off many times when asked to transition once, greatly reducing the effectiveness of the circuit and greatly increasing the switching loss in the transistor.
If you want to protect the IC's gate driving pin from the discharging FET gate pulling it below ground voltage, you'd do that with a reverse biased schottky from the pin to ground, as close to the pin as possible. You can also have one to clamp the pin to no more than Vcc although that tends to be less of an issue.
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