Maximizing MOSFET Switching Speed with High Voltage Pulse Techniques

[ctech4285]

ok looking at datasheets for mostfet there is source/drain rise and fall time. does this only depend on the voltage rise fall time of the gate?
so if you apply a voltage to the gate it will take a wile until the voltage of the actual gate reaches that of the applied voltage because of resistance and capacitance of the gate. so you could apply a very high voltage for a short a time to charge discharge the gate as fast as you possible want. maybe a few 100V timed to exactly the time needed for the gate to reach let's say 10V, maybe nano/pico seconds. now of course there will be a point at which you burn enough energy to blow up the mosfet

 

[phyzguy]

Since the gate has distributed resistance and capacitance, it acts like an RC transmission line. This means there is a time delay to turn on the gate, no matter how much voltage you apply. Also, it takes a finite time for the channel to form once the threshold voltage is exceeded, since the carriers to form the channel need to flow out from the source or drain. Mosfets can turn on very quickly (in ps), but the turn on time can never be zero.

 

[haael]

now of course there will be a point at which you burn enough energy to blow up the mosfet

That's the reason CMOS circiuts blow up when you overclock them.

 

[ctech4285]

so the entire process is just a electrons flowing from the gate. and so you can model this as restive flow from he gate...thank for clarifying this!