Statistical method of noise estimation in a synchronous system

A process to analyze coupled noise within a synchronous digital machine is described. A method that considers the spatial relationship of the noise generating components, as well as the timing of the incident pulses, is discussed. Consideration is given to factors such as path delay, reflected noise, driver slew rate, noise pulse width, termination, net topology, noise from other sources and the probabilistic nature of the time when a signal is launched, as well as other parameters. The result is a probability distribution for noise on the circuit and a noise versus time envelope. The method is more accurate than previous techniques due to timing and statistical considerations. A multilayer multichip package is considered. Treatment of the resultant output is discussed and compared to simpler deterministic methods. The failure criterion, critical time periods and some sources of errors are also considered