Design and VLSI Implementation of DDR SDRAM Controller for High Speed Applications

Synchronous DRAM (SDRAM) has become a mainstream memory of choice in design due to its speed, burst access and pipeline features. For high-end applications using processors, the interface to the SDRAM is supported by the processor's built-in peripheral module. However, for other applications, the system designer must design a controller to provide proper commands for SDRAM initialization, read/write accesses and memory refresh. DDR SDRAM uses double data rate architecture to achieve high-speed data transfers. DDR SDRAM (referred to as DDR) transfers data on both the rising and falling edge of the clock. This DDR controller is typically implemented in a system between the DDR and the Processor.