Mosfet triggering problem in proteus

Thread Starter


Joined Jul 26, 2011
Hi , I struggling at triggering of mosfet in proteus simulation . Without gate supply mosfet turned on .I dont know whether to add any component please let me know if you know. I attached simulation image .



Joined Dec 4, 2009
It is not clear as to what you intend this circuit to do.
Firstly, if you press the switch, then 12V is applied to the opto's diode and will blow that instantly.
Again the MOSFET is connected across 200V and ground. If it turns on, then it will also blow instantly as it shorts 200V to ground.
MOSFET's gate has a very high input impedance and should not be left open. A 10K resistor to ground (source) is normal.