What does Burst Length in DDR SDRAM......

ddr burst length

what does the Burst length in DDR SDRAM refer to......

DDR1 has a Burst length of 2
DDR2 has a Burst length of 4
DDR3 has a Burst length of 8

Thanks.....

dram burst length

Hi,
It indicates how many data bytes are writern are read from DDR sdram when write or read command is given along with row and coloumn address.

ddr burst

Assuming we have a data bus width of 4 bytes, i think burst length means, how many 4 bytes are written or read.

so, for a burst length of 4, we have 4x4 = 16 bytes of information.

sdram burst length

Burst length referes to the amount of data read/written after a read/write command is presented to the DDR/SDRAM/QSDRAM.....controller.

This effectively reduces the latency for r/w operations

Differenciating to the older DRAM's,
Suppose we need to 8 words from memory
In normal dram after a read command is given the data fetch time is say 1ns, so it will take 8ns and 8 read commands for complete operation

But for a SDRAM, the first command will take 1 ns and further reads dont need a read command since its mentioned as burst of 8 it will read the remaining 7 words in say each at .5ns and finally we have 8 data at 4.5ns with only one read operation

So burst operation reduces latency when accesing consecutive memory locations
others a burst size of 1 is like normal r/w operation