The introduction of the first SDRAM interface, in 1997, marked the dawn of the high-speed memory interface age. Since then, designs have migrated through SDR (single data rate), DDR (double data rate), and now DDR2 memory interfaces to sustain increasing bandwidth needs in products such as graphics accelerators and high-speed routers. As a result of its highbandwidth capabilities, DDR and DDR2 technology is used in nearly every sector of the electronics design industry-from computers and networking to consumer electronics and military applications.

Some of the most significant changes incorporated into DDR2 include on-die termination for data nets, differential strobe signals, and signal slew rate derating for both data and address/command signals. Taking full advantage of these new features will help enable you to design a robust memory interface that will meet both your signal integrity and timing goals.

Reprinted with permission from Xcell Journal / First Quarter 2006. Article © Xcell Journal.