Timing Measurement Problems and Solutions in Source Terminated Memory Systems with Inaccessible Probing Points

This paper discusses the common problem of making setup and hold measurements in memory systems where the desired probing point is inaccessible. Timing measurement problems of this type are problematic not only in skew due to incorrect probing locations, but also due to waveform distortions due to reflections created by various termination schemes. The paper considers various problems specifically in termination methods utilized in memory systems and offers some solutions and methods for mitigating measurement problems. A real-life example in a QDR memory system is used.
DesignCon 2010




Timing Measurement Problems and
Solutions in Source Terminated
Memory Systems with Inaccessible
Probing Points


John Kenney, Juniper Networks
JKenney@Juniper.com

Peter J. Pupalaikis, LeCroy Corporation
PeterP@LeCroy.com
Abstract
This paper discusses the common problem of making setup and hold measurements in memory
systems where the desired probing point is inaccessible. Timing measurement problems of this
type are problematic not only in skew due to incorrect probing locations, but also due to
waveform distortions due to reflections created by various termination schemes. The paper
considers various problems specifically in termination methods utilized in memory systems and
offers some solutions and methods for mitigating measurement problems. A real-life example in