File used by Asymptote, a vector graphics language and program used for specifying and generating technical drawings; can specify complex data structures as well as the logic used for generating the vector graphic; used for typesetting mathematical figures. The labels and equations specified in Asymptote are typeset with LaTeX, a high-quality typesetting system.
File used by LTspice, a Spice III circuit simulation program; contains circuit component symbols, which specify the circuit component shape and pin configuration; enables a circuit component to be configured properly after being visually dropped into a circuit schematic (.ASC file). ASY files are saved in a plain text format.
The asy file extension is associated with witcherCAD III/LTspice IV, developed by Linear Technology Corporation.