K4N26323AE Datasheet, PDF (24/52 Pages) Samsung semiconductor – 128Mbit GDDR2 SDRAM

K4N26323AE-GC
128M GDDR2 SDRAM
Burst Write with Auto-Precharge
If A8 is high when a Write Command is issued, the Write with Auto-Precharge function is engaged. The GDDR2 SDRAM
automatically begins precharge operation after the completion of the burst write plus write recovery time (tWR).
Interruption of the Write with Auto-Precharge function is prohibited. Active command of same bank can be issued
WL+tWR+tRP+BL/2 cycles later from the Write with Auto-Precharge command. The bank undergoing Auto-Precharge
from the completion of the write burst may be reactivated if the following two conditions are satisfied.
(1) The data-in to bank activate delay time (tWR + tRP) has been satisfied.
(2) The RAS cycle time (tRC) from the previous bank activation has been satisfied.
Burst Write with Auto-Precharge : AL = 0, WL = 1, t_WR = 5, t_RP=8(for the same bank)
0
1
2
3
4
7
8
9
16
CK, CK
CMD
A8 = 1
Post CAS
WRITE A
NOP
NOP
NOP
DQS
DQs
WL=1
DINA₀ DINA₁ DINA₂ DINA₃
NOP
NOP
NOP
NOP
Auto Precharge Begins
> = t_WR
> = t_RP
Bank A
Active
Burst Write with Auto-Precharge (AL=0)
Asserted
command
WRITE
WRITE with Auto Precharge
READ
READ with Auto Precharge
Active
Precharge
All Bank Precharge
1~7
Illegal
Illegal
Illegal
Illegal
Illegal
Illegal
Illegal
For same bank
8
9 ~ 15
Illegal Illegal
Illegal Illegal
Illegal Illegal
Illegal Illegal
Illegal Illegal
Illegal Illegal
Legal
Legal
16
Illegal
Illegal
Illegal
Illegal
Legal
Illegal
Legal
1
Illegal
Illegal
Illegal
Illegal
Legal
Legal
For different bank
2~6
Legal
Legal
Illegal
Illegal
Legal
Legal
-
7
Legal
Legal
Legal
Legal
Legal
Legal
*When AL(Additive Latency) is 1, a active command for same bank can be issued from 17th cycle , a READ or READ with Auto Pre-
charge command for different bank can be issued from 8th cycle and others are same with AL=0.
* All Bank Precharge command can be issued from 8th cycle.
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Rev. 1.7 (Jan. 2003)