Dynamic Random Access Memory:Prefetch and Pipelined Architecture in SDRAMs.

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Prefetch and Pipelined Architecture in SDRAMs

The system clock activates the SDRAM architecture. In order to speed up the average access time, it is possible to use the system clock to store the next address in the input latch or to be sequentially clocked out for each address access output from the output buffer, as shown in Figure 55.13 [15].

During the read cycle of the prefetch SDRAM, more than one data word is fetched from the memory array and sent to the output buffer. Using the system clock to control the prefetch register and buffer, multiple words of data can be sequentially clocked out for each address access. As shown in Figure 55.13, the SDRAM has a 6-clock-cycle RAS latency to prefetch 4-bit data.

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