13.3.2 source attribute

The source= attribute is used to specify that a symbol has underlying schematics. This attribute is attached directly to a component.

This attribute should only be attached to instantiated components in schematics. Attach the attribute to a component and specify the filename (not the path) of the underlying schematic (like block.sch) for the value. The specified schematic must be in a source-library path. See Legacy configuration files still in use. This attribute can be attached multiple times with different values which basically means that there are multiple underlying schematics.

Examples:

source=underlying.sch
source=memory.sch