Hi,
I am using the TC4452 fet driver IC, to drive two mosfet gates, with separate gate resistors. Is it a good idea to put a Schottky diode across the gate resistors to speed up the fet turn off times, or can this cause gate voltage oscillations? The switching speed is 100kHz and max gate voltage is 17Volts. Estimated turn on switching time is somewhere around 20ns.
cheers, Jamie
Theres always a tradeoff when selecting switching speed for the fets. you can go very fast but you will greatly increase the noise in the system due to di/dt and the inevitable inductance along the current path.
You'd be suprised how large of a gate resistor you can use that will knock the noise down significantly without seriously affecting the efficiency of the power conversion. (losing 1-2%)
If you put a schottkey, I would add a resistor in series with it so you can tune both the turn on and turn off.
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