One embodiment of the present invention provides a system for defining signal timing for an integrated circuit device. The system operates by first creating a virtual timing reference plane for the integrated circuit device. A first signal line is then routed from a semiconductor die within the integrated circuit package to a first external connection of the integrated circuit package. Next, the system generates a first escape pattern for a first circuit trace on a printed circuit board from the first external connection to the virtual timing reference plane. This first escape pattern specifies a route from where the first external connection meets the printed circuit board to the virtual timing reference plane. Finally, the system establishes a first set of signal timings for a combination of the first signal line and the first circuit trace at the virtual timing reference plane.