The emerging DDR3 (Double Data Rate 3rd version) memory standard will extend the performance range of DDR memories considerably, while maintaining some amount of backwards compatibility with the existing DDR2 (Double Data Rate 2nd version) memory standard. It is important to understand the similarities and differences between the DDR3 standard and the existing DDR2 standard to derive the maximum benefit from the new standard while re-using as much as possible from any previous DDR2 memory interface design.