Hi Guys,

VGS=12V
Rg=47R, 0603 package
Is there any scope of damaging this resistor ?

Drain Current = 400mA

How do we calculate gate current for MOSFET ?

Thanks in advance !

 

Hi Guys,

VGS=12V
Rg=47R, 0603 package
Is there any scope of damaging this resistor ?

Drain Current = 400mA

How do we calculate gate current for MOSFET ?

Thanks in advance !

You can calculate current through the resistor in the same way as for charging a capacitor.

In your specific case, remember that wattage ratings for resistors are basically temperature ratings with continuous current. For very short pulses of current, they can tolerate much higher wattage (I^2R). One would need to know in addition the gate capacitance and pulse frequency at a minimum. Drain current doesn't enter into the equation. I have seen very large, industrial mosfet modules with only 1/4W gate resistors.

 

You can calculate current through the resistor in the same way as for charging a capacitor.

In your specific case, remember that wattage ratings for resistors are basically temperature ratings with continuous current. For very short pulses of current, they can tolerate much higher wattage (I^2R). One would need to know in addition the gate capacitance and pulse frequency at a minimum. Drain current doesn't enter into the equation. I have seen very large, industrial mosfet modules with only 1/4W gate resistors.

thanks,

I am testing for 0603 package @ 100mW resistor .

Thanks again !!!

 

Calculations for driving MOSFETs -

https://toshiba.semicon-storage.com/info/docget.jsp?did=59460

http://www.ti.com/lit/slua618

https://www.infineon.com/dgdl/an-937.pdf?fileId=5546d462533600a40153559ea1481181


Regards, Dana.