resistance MOSFET gate source

[yassin.kraouch]

i am using this MOSFET https://www.fairchildsemi.com/ds/FD/FDS9934C.pdf
i see in this thread https://www.edaboard.com/threads/166905/ that i should connect a resistor between gate and source, but this is for voltage more than 12V, is it useful for my MOSFET ?

 

[WimRFP]

Whether or not this is useful depends on the circuitry and external (transient) voltages that can enter the circuit. To get a useful answer please post a schematic.

 

[yassin.kraouch]

the problem is so simple and explained in the thread that i give the link, is this resistor useful for my 3.3V ?

 

[WimRFP]

the problem is so simple and explained in the thread that i give the link, is this resistor useful for my 3.3V ?

Based on the info provided, I can't help you, sorry.

 

[dick_freebird]

The main use is to assert control when the driver may be unreliable (like during
power-up). We don't know what your 3.3V is doing, nor how you're using the FETs
nor the consequences of misbehavior. These are things you have to think through
based on your particulars. What happens if (say) your gate was allowed to float
to 1.5V and put the FET into a few ohms on resistance state, maybe oscillate?

If you don't know, then you may want to just safety-strap it. But that costs
precious battery power all the time when "on".

Free answers are nice but they aren't a substitute for analysis and judgment.

 

[goldsmith]

Dear friends
Hi
that resistor is just for discharging the gate source capacitor and its value is between 1K to 39K.