MT48H32M32LFB5-6 IT:B Micron, MT48H32M32LFB5-6 IT:B Datasheet - Page 43

• Manufacturer Part Number: MT48H32M32LFB5-6 IT:B
• Manufacturer: Micron

READ Operation
PDF: 09005aef8404b23d
y68m_mobile_lpsdr.pdf – Rev. D 1/11 EN
READ bursts are initiated with a READ command, as shown in Figure 7 (page 25). The
starting column and bank addresses are provided with the READ command, and auto
precharge is either enabled or disabled for that burst access. If auto precharge is ena-
bled, the row being accessed is precharged at the completion of the burst. In the follow-
ing figures, auto precharge is disabled.
During READ bursts, the valid data-out element from the starting column address is
available following the CAS latency after the READ command. Each subsequent data-
out element will be valid by the next positive clock edge. Figure 16 (page 45) shows
general timing for each possible CAS latency setting.
Upon completion of a burst, assuming no other commands have been initiated, the DQ
signals will go to High-Z. A continuous page burst continues until terminated. At the
end of the page, it wraps to column 0 and continues.
Data from any READ burst can be truncated with a subsequent READ command, and
data from a fixed-length READ burst can be followed immediately by data from a READ
command. In either case, a continuous flow of data can be maintained. The first data
element from the new burst either follows the last element of a completed burst or the
last desired data element of a longer burst that is being truncated. The new READ com-
mand should be issued x cycles before the clock edge at which the last desired data ele-
ment is valid, where x = CL - 1. This is shown in Figure 16 (page 45) for CL2 and CL3.
Mobile LPSDR devices use a pipelined architecture and therefore do not require the 2n
rule associated with a prefetch architecture. A READ command can be initiated on any
clock cycle following a READ command. Full-speed random read accesses can be per-
formed to the same bank, or each subsequent READ can be performed to a different
bank.
43
Micron Technology, Inc. reserves the right to change products or specifications without notice.
1Gb: x32 Mobile LPSDR SDRAM
© 2010 Micron Technology, Inc. All rights reserved.
READ Operation