Hey guys, i am posting this just to make sure the gate drive waveform is ok.
I am currently driving one MOSFET with the gate drive circuit but plan to add a second, so i expect my rise time to change when i am charging twice the gate capacitance.
The PWM frequency i am using for switching is 25Khz.
Anyway, the switch on appears to be fast enough, the rise to the miller capacitance plateau appears near vertical.
Though, i am wondering if the switch off time is OK. It appears that it takes longer to discharger the miller capacitance than it takes to charge it.
The datasheet does say that that the switch off delay is three times the magnitude of the switch on delay.
The gate drive is an fod3180 gate drive optocoupler, so the gate is being pulled down at turn off.
My fet gets rather hot at low PWM duty ( i will definitely need to heat sink it) and i am just wanting to clarify that the gate drive isn't causing the temperature rise at low duty.
I am currently driving one MOSFET with the gate drive circuit but plan to add a second, so i expect my rise time to change when i am charging twice the gate capacitance.
The PWM frequency i am using for switching is 25Khz.
Anyway, the switch on appears to be fast enough, the rise to the miller capacitance plateau appears near vertical.
Though, i am wondering if the switch off time is OK. It appears that it takes longer to discharger the miller capacitance than it takes to charge it.
The datasheet does say that that the switch off delay is three times the magnitude of the switch on delay.
The gate drive is an fod3180 gate drive optocoupler, so the gate is being pulled down at turn off.
My fet gets rather hot at low PWM duty ( i will definitely need to heat sink it) and i am just wanting to clarify that the gate drive isn't causing the temperature rise at low duty.
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