Statistical modeling of a multi-drop source synchronous bus

Using the source synchronous switching technique, high data rates can be achieved on the system board. When designing a source synchronous board, the goal is to minimize the variations in the differential delay between the data and strobe lines. This delay is often affected by jitter caused by power supply noise, cross talk, reflections and other signal integrity violations. This paper investigates the inter-relationships between electrical parameters in a printed circuit board to the physical manufacturing parameters for a source synchronous bus. Using sensitivity functions and statistical distributions of the physical parameters, the variations of the electrical parameters are computed. The correlation matrix between the electrical parameters can be used to understand the sensitivity of various electrical and physical parameters for the performance of the bus. This information can be used for redesigning boards by accounting for manufacturing variations.