IC not working when load connected

[FreshmanNewbie]

This circuitry works perfectly without any load (the gate charges to 35 volts, and the MOSFET is fully opened), but when I connect a load (2.5A or more) and disconnect the FET, the FET immediately breaks (tried on resistive load )

MOSFET Datasheet



Can someone help?

 

[stenzer]

Hi,

which supply is used to generate your 3.3 V or the supply of the MCU (?) to control Q15?

BR

 

[dick_freebird]

What exactly does "disconnect the FET" mean? It might
have something to do with why / how the FET "breaks".
Like, open gate means "oscillate yourself to death"?

You could / ought to instrument it up, the D, G, S of
the FET and a trigger source, and do what you did whilst
taking pictures.

 

[kxie]

Your description is not sufficiently detailed. Please elaborate what "disconnected the FET" means (as others have asked for) as well as what exactly you observed that led you to believe the device becomes "broken".

I will point out that in the datasheet you linked, the Vgs maximum is listed as +/- 20V. If you are indeed charging it up to 35V, then you cannot expect the device to survive, let alone behave correctly.