Datasheet

Figure 24 — Write Burst (min. and max. tDQSS)
7.6.1 Write to Write
Data for any WRITE burst may be concatenated with or truncated with a subsequent WRITE command. In either case, a
continuous flow of input data, can be maintained. The new WRITE command can be issued on any positive edge of the clock
following the previous WRITE command.
The first data-in element from the new burst is applied after either the last element of a completed burst or the last desired data
element of a longer burst which is being truncated. The new WRITE command should be issued X cycles after the first WRITE
command, where X equals the number of desired data-in element pairs.
Figure 25 shows concatenated write burst of 4
. An example of non-consecutive write bursts is shown in Figure 26. Full-
speed random write accesses within a page or pages can be performed as shown in Figure 27.
7.6.2 Write to Read
Data for any Write burst may be followed by a subsequent READ command. To follow a Write without truncating the write burst,
tWTR should be met as shown in Figure 28.
Data for any Write burst may be truncated by a subsequent READ command as shown in Figure 29. Note that the only data-in
pairs that are registered prior to the tWTR period are written to the internal array, and any subsequent data-in must be masked
with DM.
7.6.3 Write to Precharge:
Data for any WRITE burst may be followed by a subsequent PRECHARGE command to the same bank (provided Auto
Precharge was not activated). To follow a WRITE without truncating the WRITE burst, tWR should be met as shown in Figure 30.
Data for any WRITE burst may be truncated by a subsequent PRECHARGE command as shown in Figure 31. Note that only data-
in pairs that are registered prior to the tWR period are written to the internal array, and any subsequent data-in should be masked
with DM, as shown in Figure 31. Following the PRECHARGE command, a subsequent command to the same bank cannot be
issued until tRP is met
AS4C16M16MD1
256Mb MOBILE DDR SDRAM
Confidential
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Ver.1.1 Oct.2015