MOSFET failure & protection

[ST Migration account]

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A P-channel MOSFET is currently used for switching the solenoid.

Case 1:
Is it possible for the MOSFET to fail?

Case 2:
If the MOSFET fails, will it become an open circuit or a short circuit?

Case 3:
If the MOSFET fails in short-circuit condition, how can the circuit be protected  

[ST Migration account]

The ignition line of the vehicle is connected to the transistor base, and the transistor collector drives the MOSFET gate. The MOSFET source is connected to the battery supply, while the drain is connected to the positive terminal of the solenoid.

In case the MOSFET fails short between source and drain, the solenoid remains continuously energized. Kindly suggest suitable protection methods for this condition.

[Andrew Neil]

As  @Peter BENSCH  said, this sounds like just a generic electronics question - nothing to do with ST.

This is ST's forum; provided and run by ST for discussions about ST products - it's not a general electronics forum.

See this - which links to this.

 

PS:

It's far more effective to post a circuit diagram (aka schematic) than try to describe an electronic circuit in words.