Will Shorted Power Fet Causes Power IC To Blow?
I have a Sony laptop adapter for repair that has a fet 4n60 and an IC (AS3843)(smd) . the FET was out of order and I changed it and a 0.33 ohm resistor was bad I changed it too I hope that the AS3843 will be OK
From my repair experience, usually when the power FET shorted/blow the power IC will also give way. If one did not check the surrounding components and did not replace the power IC there is a chance the power FET that you have just replaced will blow again. In summary, check all corresponding components, replace the power FET and also the power FET. Don’t forget to check on the transformer primary winding with Blue Ring Tester and the secondary output diodes.