Compound Noise Analysis in Digital Circuits Using Blind Source Separation

Abstract

In the past decade there have been significant efforts to analyze and solve signal integrity issues in pre-nanometer circuits. However, most of these techniques apply to single noise source, and cannot take into account the evolving reality of multiple noise sources interacting with each other. With the scaling of the technology into nanometer regime, maintaining historical rate of performance and signal integrity have become very challenging due to compound noise effects. Noise measurement made at an evaluation node will reflect the cumulative effect of all the active noise sources, while individual and relative severity of various noise sources will determine what types of remedial steps can be adopted, pressing the need for the development of algorithms that study the cumulative noise effects, and analyze the relative contributions of different noise sources. This paper presents a novel method to analyze the characteristics of compound noise effect in very high performance integrated circuits. The algorithm extracts the time characteristics of individual noise sources from the measured voltage in order to study the contribution of each source separately, by applying the technique of blind source separation, which is based on the assumption that the different sources of noise are statistically independent over time. The estimated noise sources can aid in timing and spectral analysis and yield better design techniques.