Now-a-days, DDR SDRAM (Double Data Rate Synchronous Dynamic Random Access Memory) has become the most popular class of memory used in computers due to its high speed, burst access and pipeline feature. For high speed applications like image/video processing, signal processing, networking, etc. DDR SDRAM is widely used. The basic operations of DDR SDRAM controller are similar to that of SDR (Single Data Rate) SDRAM; however, there is a difference in the circuit design; DDR simply use sophisticated circuit techniques to achieve high speed.