DDR transmission standard

Standard DDR SDRAM is divided into DDR 200, DDR 266, DDR 333 and DDR 400, with standard operating frequencies of 100MHz, 133MHz, 166MHz and 200MHz, and corresponding memory transfer bandwidths of 1.6GB/sec, 2.12GB/sec, 2.66GB/sec and 3.2GB/sec, respectively. Non-standard ones include DDR 433, DDR 500, etc. Beginners are often confused by words such as DDR 266 and PC 2100. Here we need to explain that DDR 266 and PC 2100 are actually the same thing, just expressed in different ways. DDR 266 refers to the operating frequency of the memory (the actual operating frequency is 133MHz, equivalent to 266MHz SDRAM), while PC 2100 refers to its memory transfer bandwidth (2100MB/sec). Similarly, PC 1600 is DDR 200, PC 2700 is DDR 333, and PC 3200 is DDR 400.

DDR SDRAM memory transmission standard table: