Unfortunately I do not know, what has happened. I received the PSU in a non-working condition with information that it blows fuses in the apartment. The context and the wording suggests that the power supply experienced a few shorts in the two-digit amps range. Besides this poor chip, primary side had rectifier with shorts and epoxy on one leg broken out, at least one MOSFET killed and a 10A fuse blown. But only this one got hit so hard that it literally exploded.
Coincidentally Zeptobars’ last post is about
Power Integrations INN2605K. A far cousin that shares many features of this one. They also have
TNY264, a specimen from the earlier iteration of this family.
You're going to need some really small bodge wires and solder tip.
I should also buy one of those fancy focused ion beam deposition devices to fix the transistor, which seems to be shattered into pieces. I have seen some used power supplies for those on eBay for a bargain price of $40k.
