k4s643232c Samsung Semiconductor, Inc., k4s643232c Datasheet - Page 18

• Manufacturer Part Number: k4s643232c
• Description: 2m X 32 Sdram 512k X 32bit X 4 Banks Synchronous Dram Lvttl
• Manufacturer: Samsung Semiconductor, Inc.

K4S643232C
5. Write Interrupted by Precharge & DQM
6. Precharge
7. Auto Precharge
*Note : 1. To prevent bus contention, DQM should be issued which makes at least one gap between data in and data out.
*Note : 1. t
1) Normal Write (BL=4)
1) Normal Write (BL=4)
CMD
CLK
2. To inhibit invalid write, DQM should be issued.
3. This precharge command and burst write command should be of the same bank, otherwise it is not precharge
4. For -55/60/70/80/10, tRDL=1CLK product can be supported within restricted amounts and it will be distinguished by bucket code "NV"
. From the next generation, tRDL will be only 2CLK for every clock frequency.
2. Number of valid output data after row precharge : 1, 2 for CAS Latency = 2, 3 respectively.
3. The row active command of the precharge bank can be issued after t
4. For -55/60/70/80/10, tRDL=1CLK product can be supported within restricted amounts and it will be distinguished by bucket code "NV"
. From the next generation, tRDL will be only 2CLK for every clock frequency
DQ
interrupt but only another bank precharge of four banks operation.
CMD
The new read/write command of other activated bank can be issued from this point.
At burst read/write with auto precharge, CAS interrupt of the same/another bank is illegal.
CLK
RDL
DQ
DQM
: Last data in to row precharge delay
CMD
CLK
DQ
WR
D
0
WR
D
0
WR
D
D
0
1
D
1
D
D
1
2
D
2
D
D
2
3
D
Auto Precharge Starts
3
tRDL
Note 1,4
D
Masked by DQM
3
Note 2
PRE
Note 3,4
PRE
Note 3,4
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2) Normal Read (BL=4)
2) Normal Read (BL=4)
DQ(CL2)
DQ(CL3)
DQ(CL2)
DQ(CL3)
RP
CMD
CMD
CLK
CLK
from this point.
RD
RD
Q
D
0
0
REV. 1.1 Nov. '99
CMOS SDRAM
Q
Q
D
D
1
0
0
1
Auto Precharge Starts
PRE
Q
Q
D
D
2
1
2
1
Q
Q
D
D
Note 2
Note 3
3
2
3
2
1
Q
D
3
3
2