Simmtronics Semiconductors Ltd manufactures Double Data Rate Synchronous Dynamic Random Access Memory. Simmtronics Semiconductors Ltd is an ISO 9001 accredited company. The Company also manufactures various types of memory modules, motherboards and VGA cards and led products. The Double Data Rate Synchronous Dynamic Random Access Memory, also known as DDR SDRAM, is used in computers. The Double Data Rate Synchronous Dynamic Random Access Memory is available in memory modules of 1024MB, 512MB, 256MB and 128MB. This Random Access Memory gives a transfer rate of [memory bus clock rate] X 2 [for dual rate] X 64 [number of bits transferred] / 8 [number of bits/byte].