We all do goof up, either in our understanding, our design, or in our construction. And when its none of these three, its the supplier who can contribute to that “busted” circuit!
I had constructed a circuit to drive 350mA CC (constant current) through a string of LEDs. Well, as luck would have it, the IC we placed wasn’t really in a good shape. This MC34063 from ST Microelectronics was one rotten apple in our 100+ inventory. Just one bad IC. And see what happened to it when we powered up the circuit!
It literally blew its top!