Efficient and accurate eye diagram prediction for high speed signaling

This paper introduces an accumulative prediction method to predict the eye diagram for high speed signaling systems. We use the step responses of pull-up and pull-down to extract the worst-case eye diagram, including the eye height and jitter. Furthermore, the method produces the input patterns of the worst-case intersymbol interference. The algorithm handles signals of either symmetric or asymmetric rise/fall time. Experimental results demonstrate the accuracy and efficiency of the proposed method.

I. Introduction

In high speed signaling system, the distortion, noise, and interference on signal waveforms constrain the system performance [1], [2], e.g. bandwidth and power. An eye diagram provides one fundamental and intuitive view to evaluate the quality of the channel. Traditional methods execute the time domain simulation to obtain the eye diagram with a pseudorandom bit sequence (PRBS) as the input stimulus. Due to the limited length of the sequence, the simulated eye size is usually larger than the worst-case.