"gore" wrote in message
...
I work at an electronics contract manufacturimg facility. We do work for
several companies and I wonder why they use different labels on the
schematics and pcb's to refer to IC's. Some of them have a U1, an A1, and X1,
or an IC1. Why do they do this? Is there a standard used to label IC's in a
schematic? Just curious why this is.

U is quite common for ICs. X ought to be a crystal, typically. IC1 is
probably from some smaller design house where they're making up their own
standard as they go along (they probably also use, e.g., LED1...).

There is no universal standard, although growing companies often decide at
some point to go out and review some documented choices, such as what the IPC
recommends.