68kMLA Classic Interface

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Mac classic blows MOSFET
Posted by: bengi3 on 2018-06-01 22:23:40
Can that cap go bad after a short that blow fuse and mosfet?

Posted by: techknight on 2018-06-02 14:57:01
Yes. 

If the IC goes bad for any reason, the VCC supply to that IC could spike beyond the capacitors ratings and damage it internally. 

Case in point: I used to work on Infocus LP520 and LP540 projectors back in the day. 

There is a Viper100A switching regulator ICs very similar to that one that use a capacitor as a VCC bus filter. when that IC goes bad, it literally launches that capacitor across the room and leaves paper and foil everywhere. 

So yep. 

Posted by: timoog on 2026-02-13 10:52:58
the 47uf 25v capacitor is a critical one. Without it, the IC will fail.
Hi @techknight is that CP15? and can an 'ordinary' electrolytic aluminium type capacitor be used - looks like some special kind of capacitor? cheers!
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