EMD56324P Datasheet, PDF (28/45 Pages) Emerging Memory & Logic Solutions Inc – 256M: 8M x 32 Mobile DDR SDRAM

Preliminary
EMD56324P
256M: 8M x 32 Mobile DDR SDRAM
DM Masking < Burst Length = 8 >
0
1
2
CKB
CK
Command WRITE
NOP
DQS
t_DQSS
NOP
3
NOP
4
NOP
5
6
NOP
NOP
7
NOP
8
NOP
DQ’s
Din 0 Din 1 Din 2 Din 3 Din 4 Din 5 Din 6 Din 7
DM
t_DS t_DH
Masked by DM = H
PRECHARGE
The PRECHARGE command is used to deactivate the open row in a particular bank or the open row in all banks. The
bank(s) will be available for a subsequent row access some specified time (tRP) after the PRECHARGE command is
issued. Input A10 determines whether one or all banks are to be precharged, and in the case where only one bank is
to be precharged, inputs BA0, BA1 select the bank. When all banks are to be precharged, inputs BA0, BA1 are treated
as Don’t Care. Once a bank has been precharged, it is in the idle state and must be activated prior to any READ or
WRITE commands being issued to that bank.
Read with Auto Precharge < Burst Length = 4, CAS Latency = 2, 3 >
0
CKB
CK
Command _{BANK A}
ACTIVE
DQS
1
NOP
DQ’s
DQS
DQ’s
2
3
4
5
6
7
8
9
NOP
NOP
t_RAS(min.)
READ
Auto Precharge
NOP
NOP
NOP
NOP
NOP
CL = 2
Dout0 Dout1 Dout2 Dout3
t_RP
CL = 3
Begin Auto-Precharge
Dout0 Dout1 Dout2 Dout3
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Rev 0.0