Determine Value of MOSFET with no markings

[luckyind]

mosfet markings

Is there way even including a million dollar piece of equipment to determine the value of a MOSFET that has no number on it or the number have been ground off, and all you have is the part no schematics and no information, I have been told there is no way to tell, but the manufactures must have a way to tell this, there must be some way.:?:

 

[pranam77]

mosfets markings

Only way is to "guess" looking measuring the volatge fed to and the current passing through the device. There may be many companys manufacturing similar device. After grinding the name no company can say "this is our device" with the appearance and find out the name/value. Good luck

 

[FvM]

You're able to measure a lot of important parameters, e.g. Rds,on, Cgs, Gds, Cgd, gm. Possibly the manufacturer can be guessed from the case finish details. This indformation can reduce the candidate selection to a limited choice.

I think, having the circuit at his fingertips and some knowledge about it's purpose, a qualified analog designer would rather redesign the respective circuit detail than spending much effort for indentifying the exact type.