Larry Jaques wrote:


Shimming an IC? Whuffo?
Laser trimming. You burn away a little resistor material to do
the things you used to do on discrete circuits with a trimpot
and a screwdriver. Also, in digital circuits, like memories,
they used to have an extra row or two of memory cells, and a
kind of ROM that can be laser burned to swap in the spare row
for a bad one. This is all done with electronic techniques
today, like flash memory.

Jon