Floating Gate FET

Thread Starter

DC_Kid

Joined Feb 25, 2008
1,072
quik question. do MOSFET's have any floating pin issues commonly found in logic IC's? as example, if i have p-channel MOSFET and i switch the gate to ground to get FET to go "on", if i lift the gate from ground to floating is this a issue? is it best just to tie the gate to +V via a 10k or 20k resistor so it never floats??

thanks
 

Audioguru

Joined Dec 20, 2007
11,248
The gate of a Mosfet has an extremely high resistance. A very small amount of static electricity will destroy it if it is floating. A resistor to +V for a P-channel Mosfet stops the buildup of static electricity.

A Mosfet with a floating gate stays on for a long time if it was already turned on and it stays off for a long time if it was already off.
 
Top