Understanding The Value Of Signal Integrity

Historically, design engineers have used signal integrity (SI) testing as a key part of the design and development of new systems and for sustaining qualifications. Signal integrity, while extremely valuable in the engineering prototype phase, is not a panacea. In fact, its value diminishes as the product design progresses. After debug of early prototypes is complete, powerful tools that perform temperature and voltage margin testing should supplement or replace SI, especially for qualification of memory die shrinks and alternate sourcing.

Proper selection of memory design, test, and verification tools reduces engineering time and increases the probability of detecting potential problems. This technical note describes how these alternate tools can be used to the greatest advantage, from conception of a new product through end of life. It also provides a detailed description of SI, its uses, and limitations. Finally, it presents an overview of margin testing tools and the value they can add.