Application of wavelets and generalized pencil-of-function method for the extraction of noise current spectrum and simulation of simultaneous switching noise

In high performance systems, the voltage fluctuation noise caused by the simultaneous switching of circuits is an important concern in relation to signal integrity and radiated emission related issues. For proper design of the Power Distribution System the noise current is required as an input for the simulation of the simultaneous switching noise. This paper proposes a measurement based approach to estimate the noise current spectrum in a functioning computer system. Its also discusses a method for extracting the current signature needed to simulate switching noise in the system. The proposed approach is tested on a high speed functioning computer system from Sun Microsystems. Using the current source developed, simultaneous switching noise in the core power distribution network of the system has been simulated with good accuracy.