H5MS5122DFR Datasheet, PDF (33/62 Pages) Hynix Semiconductor – Mobile DDR SDRAM 512Mbit (16M x 32bit)

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Mobile DDR SDRAM 512Mbit (16M x 32bit)
H5MS5122DFR Series / H5MS5132DFR Series
READ to READ
Data from a read burst may be concatenated or truncated by a subsequent READ command. The first data from the
new burst follows either the last element of a completed burst or the last desired element of a longer burst that is
being truncated. The new READ command should be issued X cycles after the first READ command, where X equals
the number of desired data-out element pairs (pairs are required by the 2n prefetch architecture).
/CLK
CLK
Command
READ
NOP
READ
NOP
NOP
NOP
Address
DQS
BA,
Col n
CL =2
BA,
Col b
DQ
Don
Dob
CL =3
DQS
DQ
Don
Dob
Don't Care
1) Don (or b): Data out from column n (or column b)
2) BA, Col n (b) = Bank A, Column n (b)
3) Burst Length = 4 or 8 (if 4, the bursts are concatenated; if 8, the second burst interrupts the first)
4) Read bursts are to an active row in any bank
5) Shown with nominal tAC, tDQSCK and tDQSQ
Consecutive Read Bursts
A READ command can be initiated on any clock cycle following a previous READ command. Non-consecutive Reads are
shown in the first figure of next page. Random read accesses within a page or pages can be performed as shown in
second figure of next page.
Rev 1.2 / Jul. 2008
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