k4h510438 Samsung Semiconductor, Inc., k4h510438 Datasheet - Page 8

• Manufacturer Part Number: k4h510438
• Description: Ddr Sdram 512mb B-die X4, X8, X16
• Manufacturer: Samsung Semiconductor, Inc.

Note :
Command Truth Table
DDR SDRAM 512Mb B-die (x4, x8, x16)
Register
Register
Refresh
Bank Active & Row Addr.
Read &
Column Address
Write &
Column Address
Burst Stop
Precharge
Active Power Down
Precharge Power Down Mode
DM(UDM/LDM for x16 only)
No operation (NOP) : Not defined
1. OP Code : Operand Code. A
2. EMRS/MRS can be issued only at all banks precharge state.
3. Auto refresh functions are same as the CBR refresh of DRAM.
4. BA
5. If A
6. During burst write with auto precharge, new read/write command can not be issued.
7. Burst stop command is valid at every burst length.
8. DM(x4/8) sampled at the rising and falling edges of the DQS and Data-in are masked at the both edges (Write DM latency is 0).
9. This combination is not defined for any function, which means "No Operation(NOP)" in DDR SDRAM.
A new command can be issued 2 clock cycles after EMRS or MRS.
The automatical precharge without row precharge command is meant by "Auto".
Auto/self refresh can be issued only at all banks precharge state.
If both BA
If BA
If BA
If both BA
Another bank read/write command can be issued after the end of burst.
New row active of the associated bank can be issued at t
UDM/LDM(x16 only) sampled at the rising and falling edges of the UDQS/LDQS and Data-in are masked at the both edges
(Write UDM/LDM latency is 0).
0
10
~ BA
0
0
/AP is "High" at row precharge, BA
is "High" and BA
is "Low" and BA
COMMAND
1
0
0
: Bank select addresses.
Extended MRS
Mode Register Set
Auto Refresh
Self
Refresh
Auto Precharge Disable
Auto Precharge Enable
Auto Precharge Disable
Auto Precharge Enable
Bank Selection
All Banks
and BA
and BA
1
1
are "Low" at read, write, row active and precharge, bank A is selected.
are "High" at read, write, row active and precharge, bank D is selected.
1
1
is "High" at read, write, row active and precharge, bank C is selected.
is "Low" at read, write, row active and precharge, bank B is selected.
Entry
Entry
Entry
Exit
Exit
Exit
0
~ A
12
CKEn-1 CKEn
& BA
0
H
H
H
H
H
H
H
H
H
H
H
H
L
L
L
and BA
0
~ BA
1
H
H
H
1
X
X
H
X
X
X
X
X
X
L
L
L
are ignored and all banks are selected.
: Program keys. (@EMRS/MRS)
CS
RP
H
H
X
H
H
H
L
L
L
L
L
L
L
L
L
L
L
L
L
after the end of burst.
RAS
H
X
H
H
H
X
V
X
X
H
X
V
X
H
L
L
L
L
L
X
CAS
H
X
H
H
H
X
V
X
X
H
X
V
X
H
L
L
L
L
L
(V=Valid, X=Don′t Care, H=Logic High, L=Logic Low)
WE
H
H
H
H
H
H
L
L
X
L
L
L
X
V
X
X
X
V
X
BA0,1 A10/AP
V
V
V
V
X
Rev. 1.2 October, 2004
OP CODE
OP CODE
H
H
H
L
L
L
Row Address
X
X
X
X
X
X
X
DDR SDRAM
A11,A12
A0 ~ A9,
Address
Address
Column
Column
X
Note
1, 2
4, 6
1, 2
3
3
3
3
4
4
4
7
5
8
9
9