Mosel Vitelic V58C2256164SXT75, V58C2256164SXT7, V58C2256164SXT6, V58C2256804SXT8, V58C2256804SXT75 Datasheet
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MOSEL VITELIC
1
V58C2256(804/404/164)S
HIGH PERFORMANCE
2.5 VOLT 256 Mbit DDR SDRAM
4 BANKS X 8Mbit X 8 (804)
4 BANKS X 4Mbit X 16 (164)
4 BANKS X 16Mbit X 4 (404)
PRELIMINARY
V58C2256(804/404/164)S Rev.1.4 October 2002
67758
DDR333B DDR266A DDR266B DDR200
Clock Cycle Time (t
CK2
) 7.5 ns 7.5ns 10 ns 10 ns
Clock Cycle Time (t
CK2.5
) 6 ns 7ns 7.5 ns 8 ns
System Frequency (f
CK max
) 166 MHz 143 MHz 133 MHz 125 MHz
Features
■ High speed data transfer rates with system
frequency up to 166 MHz
■ Data Mask for Write Control
■ Four Banks controlled by BA0 & BA1
■ Programmable CAS
Latency: 2, 2.5
■ Programmable Wrap Sequence: Seq uential
or Interleave
■ Programmable Burst Length:
2, 4, 8 for Sequential Type
2, 4, 8 for Interleave Type
■ Automatic and Controlled Precharge Command
■ Power Down Mode
■ Auto Refresh and Self Refresh
■ Refresh Interval: 81 92 cycl e s/64 ms
■ Available in 66-pin 400 mil TSOP or 60 Ball SOC
BGA
■ SSTL-2 Compatible I/Os
■ Double Data Rate (DDR)
■ Bidirectional Data Strobe (DQS) for input and
output data, active on both edges
■ On-Chip DLL aligns DQ and DQs transitions with
CK transitions
■ Differential clock inputs CK and CK
■ Power Supply 2.5V ± 0.2V
■ QFC
options for FET control. x4 parts.
*Note: DDR 333B Supports PC2700 module with 2.5-3-3 timing
DDR 266A Supports PC2100 module with 2-2-2 timing
DDR 266B Supports PC2100 module with 2.5-3-3 timing
DDR 200 Supports PC1600 module with 2-2-2 timing
Description
The V58C2256(804/404/164)S is a four bank
DD R DRAM o rganized as 4 banks x 8M bi t x 8 (804 ),
4 banks x 4Mbit x 16 (164), or 4 banks x 16Mbit x 4
(404). The V58C2 256(804/404/16 4)S ach ieve s h igh
speed data transfer rates by employing a chip architecture that prefetches multipl e bits and then synchronizes the output data to a system clock.
All of the control, address, circuits are synchronized with the positive edge of an externally supplied clock. I/O transactions are ocurring on both
edges of DQS.
Operating the four memory banks in an interleaved fashion allows random a ccess operation to
occur at a higher rate than is possible with standard
DRAMs. A sequential and gapless data rate is possible depending on burst length, CAS
latency and
speed grade of the device.
Device U sage Chart
Operating
Temperature
Range
Package Outline CK Cycle Time (ns) Power
Temperature
Mark
JEDEC 66 TSOP II
60 SOC BGA -6 -7 -75 -8 Std. L
0°C to 70°C • • • • • • • Blank
2
V58C2256(804/404/164)S Rev. 1.4 October 2002
MOSEL VITELIC
V58C2256(804/404/164)S
60-Ball SOC BGA PIN OUT
A
B
C
D
E
F
G
H
J
K
L
M
VSSQ NC
NC VDDQ DQ3
NC
VDDQ
NC
VSSQ
VDD NC
DQ0 NC
VDDQNC
DQ1 VSSQ NC
NC NCVDDQ
NC VDD
WE
CAS
RAS
BA1 BA0
A0 A10/AP
A2 A1A5A6
A7A8
A9
CS
VREF
A12
NC
A4 A3
NC
VDDQ
VSSQ
DQ2NC
NC
CKE
A11
CK
VSSQ DQS
VSS DM
CK
VSS VDD
VSS
(
x4)
A
B
C
D
E
F
G
H
J
K
L
M
VSSQ DQ7
NC VDDQ DQ6
NC
VDDQ
NC
VSSQ
VDD DQ0
DQ1 NC
VDDQDQ2
DQ3 VSSQ NC
NC NCVDDQ
NC VDD
WE
CAS
RAS
BA1 BA0
A0 A10/AP
A2 A1A5A6
A7A8
A9
CS
VREF
A12
NC
A4 A3
DQ5
VDDQ
VSSQ
DQ4NC
NC
CKE
A11
CK
VSSQ DQS
VSS DM
CK
VSS VDD
VSS
(x8)
A
B
C
D
E
F
G
H
J
K
L
M
VSSQ DQ15
DQ14 VDDQ DQ13
DQ12
VDDQ
DQ3
VSSQ
VDD DQ0
DQ2 DQ1
VDDQDQ4
DQ6 VSSQ DQ5
LDQS DQ7VDDQ
LDM VDD
WE
CAS
RAS
BA1 BA0
A0 A10/AP
A2 A1A5A6
A7
A8
A9
CS
VREF
A12
NC
A4 A3
DQ11
VDDQ
VSSQ
DQ9DQ10
DQ8
CKE
A11
CK
VSSQ UDQS
VSS UDM
CK
VSS VDD
VSS
(x16)
123 789
123 789 123 789
X8 Device Ball PatternX4 Device Ball Pattern
X16 Device Ball Pattern
TOP VIEW
(See the ball through the package)
123 789
A
B
C
D
E
F
G
H
M
K
L
J
PIN A1 INDEX
3
MOSEL VITELIC
V58C2256(804/404/164)S
V58C2256(804/404/164)S Rev. 1.4 October 2002
66 Pin Plastic TSOP -I I
PIN CONFIGURATION
Top View
Pin Names
CK, C K Differential Clo ck Input
CKE Clock Enable
CS
Chip Select
RAS
Row Address Strobe
CAS
Column Address Strobe
WE
Write Enable
DQS (UDQS, LDQS) Data Strobe (Bidirectional)
A
0–A12
Address Inputs
BA0, BA1 Bank Select
DQ’s Data Input/Output
DM (UDM, LDM) Data Mask
V
DD
Power (+2.5V)
V
SS
Ground
V
DDQ
Power for I/O’s (+2.5V)
V
SSQ
Gro u n d for I/O’s
NC Not connected
VREF Reference Voltage for Inpu t s
QFC
FET Control
1
2
3
4
5
6
9
10
11
12
13
14
7
8
15
16
17
18
19
20
21
22
66
65
64
63
62
61
58
57
56
55
54
53
60
59
52
51
50
49
48
47
46
45
23
24
25
44
43
42
26
27
41
40
28
29
30
31
32
33
39
38
37
36
35
34
V
DD
NC
V
DDQ
NC
DQ
0
V
SSQ
V
DDQ
NC
DQ
1
V
SSQ
NC
NC
NC
NC
V
DDQ
NC
NC
V
DD
NC
WE
CAS
RAS
CS
NC
BA
0
BA1
V
SS
NC
V
SSQ
NC
DQ
3
V
DDQ
V
SSQ
NC
DQ
2
V
DDQ
NC
NC
NC
NC
V
SSQ
DQS
NC
V
REF
V
SS
DM
CK
CK
CKE
NC
A
12
A
11
A
9
AP/A10
A0
A
1
A
2
A
3
V
DD
V
DD
DQ
0
V
DDQ
NC
DQ
1
V
SSQ
V
DDQ
NC
DQ
3
V
SSQ
NC
NC
NC
DQ
2
V
DDQ
NC
NC
V
DD
NC
WE
CAS
RAS
CS
NC
BA
0
BA1
AP/A10
A0
A
1
A
2
A
3
V
DD
V
DD
DQ
0
V
DDQ
DQ
1
DQ
2
V
SSQ
V
DDQ
DQ
5
DQ
6
V
SSQ
DQ
7
NC
DQ
3
DQ
4
V
DDQ
LDQS
NC
V
DD
Q
FC/NC
LDM
WE
QFC/NC QFC/NC
CAS
RAS
CS
NC
BA
0
BA1
AP/A10
A0
A
1
A
2
A
3
V
DD
A
8
A
7
A
6
A
5
A
4
V
SS
A
11
A
9
A
8
A
7
A
6
A
5
A
4
V
SS
A
11
A
9
A
8
A
7
A
6
A
5
A
4
V
SS
V
SS
DQ
7
V
SSQ
NC
DQ
5
V
DDQ
V
SSQ
NC
DQ
4
V
DDQ
NC
NC
NC
DQ
5
V
SSQ
DQS
NC
V
REF
V
SS
DM
CK
CK
CKE
NC
A
12
V
SS
DQ
15
V
SSQ
DQ
14
DQ
13
V
DDQ
V
SSQ
DQ
10
DQ
9
V
DDQ
DQ
8
NC
DQ
12
DQ
11
V
SSQ
UDQ
S
NC
V
REF
V
SS
UDM
CK
CK
CKE
NC
A
12
66 PIN TSOP (II)
(400mil x 875 mil)
Bank Address
BA0-BA1
Row Address
A0-A12
Auto Precharge
A10
8Mb x 16
16Mb x 8
32Mb x 4
MOSEL VITELIC
V58C2256(804/404/164)S
4
V58C2256(804/404/164)S Rev. 1.4 October 2002
Block Diagram
Row decoder
Memory array
Bank 0
8192 x 1024
x 8
Column decoder
Sense amplifier & I(O) bus
Row decod e r
Memory array
Bank 1
Column decoder
Sense amplifier & I(O) bus
Row decoder
Memory array
Bank 2
Column decoder
Sense amplifier & I(O) bus
Row decoder
Memory array
Bank 3
Column decoder
Sense amplifier & I(O) bus
Input buffer Output buffer
DQ0-DQ
3
Column address
counter
Colum n address
buffer
Row ad dr ess
buffer
Refresh Counter
A0 - A12, BA0, BA1A0 - A9, A11, AP, BA0, BA1
Control logic & timing genera to r
CK
CKE
CS
RAS
CAS
WE
DM
Row Addresses
Column Addresses
DLL
Strobe
Gen.
Data Strobe
CK, CK
CK
DQS
QFC
8192 x 1024
x 8
8192 x 102 4
x 8
8192 x 10 24
x 8
64M x 4
V 58 C 2 256(80/40/16) 4 S X T XX
DDR SDRAM
CMOS
2.5V
256Mb, 8K Refresh
4 Banks
COMPONENT
REV LEVEL A=0.14u
COMPONENT
PACKAGE, T = TSOP S=SOC BGA
SSTL
SPEED
MOSEL VITELIC
MANUFACTURED
6 (133MHz@CL2.5))
75(133MHz@CL2.5)
x8, x4, x16
8 (125MHz@CL2.5)
7 (143MHz@CL2.5))
5
MOSEL VITELIC
V58C2256(804/404/164)S
V58C2256(804/404/164)S Rev. 1.4 October 2002
Block Diagram
Row decoder
Memory array
Bank 0
8192 x 512
x 16 bit
Column decoder
Sense amplifier & I(O) bus
Row decoder
Memory array
Bank 1
Column decoder
Sense amplifier & I(O) bus
Row decoder
Memory array
Bank 2
Column decoder
Sense amplifier & I(O) bus
Row decoder
Memory array
Bank 3
Column decoder
Sense amplifier & I(O) bus
Input bu f fer Output buffer
DQ0-DQ
7
Column address
counter
Column address
buffer
Row address
buffer
Refresh Counter
A0 - A12, BA0, BA1A0 - A9, AP, BA0, BA1
Control logi c & timing gen er ator
CK
CKE
CS
RAS
CAS
WE
DM
Row Addresses
Column Addresses
DLL
Strobe
Gen.
Data Strobe
CK, CK
CK
DQS
QFC
32M x 8
8192 x 51 2
x 16 bit
8192 x 512
x 16bit
8192 x 512
x 16bit
6
MOSEL VITELIC
V58C2256(804/404/164)S
V58C2256(804/404/164)S Rev. 1.4 October 2002
Block Diagram
Row decoder
Memory array
Bank 0
8192 x 256
x32 bit
Column decoder
Sense amplifier & I(O) bus
Row decoder
Memory array
Bank 1
Column decoder
Sense amplifier & I(O) bus
Row decoder
Memory array
Bank 2
Column decoder
Sense amplifier & I(O) bus
Row decoder
Memory array
Bank 3
Column decoder
Sense amplifier & I(O) bus
Input bu f fer Output buffer
DQ0-DQ
15
Column address
counter
Column address
buffer
Row address
buffer
Refresh Counter
A0 - A11, BA0, BA1A0 - A8, AP, BA0, BA1
Control logi c & timing gen er ator
CK
CKE
CS
RAS
CAS
WE
DM
Row Addresses
Column Addresses
DLL
Strobe
Gen.
Data Strobe
CK, CK
CK
DQS
QFC
8192 x 256
x 32 bit
8192 x 256
x 32 bit
8192 x 256
x 32 bit
16M x 16
Capacitance*
TA = 0 to 70°C, VCC = 2.5V ± 0.2V, f = 1 Mhz
*Note: Capacitance is sampled and not 100% tested.
Absol u te M aximum Ratings*
Operating temperature range..................0 to 70 °C
Storage temperature range ................-55 to 150 °C
V
DD
Supply Voltage Relative to VSS.....-1 V to +3.6V
V
DDQ
Supply Voltage Relative to V
SS
......................................................-1V to +3.6V
VREF and Inputs Voltage Relative to V
SS
......................................................-1V to +3.6V
I/O Pins Voltage Relative to V
SS
..........................................-0.5V to V
DDQ
+0.5V
Power dissipation............................ ..............1.6 W
Data out current (short circuit) ...................... 50 mA
*Note: Stresses above those listed under “Absolute Maximum
Ratings” may cause permanent damage of the device.
Exposure to absolute maximum rating conditions for
extended periods may affect de vi ce r eliability .
Inpu t Capacit ance
Symbol
Min Max Unit
BA0, BA1, CKE, CS, RAS, (CAS,
A0-A 11, WE
)
C
INI
23.0pF
Input Capacitance ( CK, CK
)C
IN2
23.0pF
Data & DQS I/O Capacitance C
OUT
45pF
Input Capacitance (DM) C
IN3
45.0pF
7
MOSEL VITELIC
V58C2256(804/404/164)S
V58C2256(804/404/164)S Rev. 1.4 October 2002
Signal Pi n D escription
Pin Type Signal Polarity Function
CK
CK
Input Pulse Positive
Edge
The system clock i nput. All in puts excep t DQs and DMs are sam pled on the r i sing edge
of CK.
CKE Input Level Active High Activates the CK signal when high and deactivates the CK signal when low, thereby ini-
tiates eit her the Power Down mode, or the Self Refres h m ode.
CS
Input Pulse Active Low CS enables t he command dec oder when low an d disables t he command decoder when
high. Wh en the co mma nd de co der i s dis ab led, ne w com m ands are i gn ored b ut pre vious
operat io ns continu e.
RAS
, CAS WEInput Pulse Active Low When sampled at th e positive ris in g edge of the cl ock, CAS, RAS, and WE define the
command to be exec ut ed by the SDR AM.
DQS Input/
Output
Pulse Active High Act iv e on both ed ges for data input and output.
Center al igned to input data
Edge aligned to output data
A0 - A12 Input Level — During a Bank Activate command cycle, A0-A12 def i nes the row address (RA0-RA12)
when sampled at the rising clock edge.
During a R ead or Write command cycle, A0-An defines th e column address (C A0-CAn)
when sam pled at the risi ng clock edge.CAn de pends on th e S DRAM organization :
64M x 4 DDR CAn = CA9, A11
32M x 8 DDR CAn = CA9
16M x 16 DDR CAn = CA8
In addition to the column ad dr ess, A10 (=AP) is used to invoke auto precharge operation
at the end of th e burst read or w r it e cycle. If A10 is high, au to pr echarge is selected and
BA0, BA1 defines th e bank to be p r echarged. I f A10 is low, aut oprecharge is disabled.
During a P re char ge co mm and c ycle , A1 0(=A P) is us ed in conj un ction w it h BA 0 and BA1
to control which bank(s) to precharge. If A10 is high, all four banks will be precharged
simultan eously regardless of st at e of BA0 and BA1.
BA0,
BA1
Input Level — Selects wh ich bank is to b e active.
DQx Input/
Output
Level — Data Input/Output pi ns operate in the same m anner as on conventional DRAMs.
DM,
LDM,
UDM
Input Pulse Active High In Write mode, DM has a latency of zero and operates as a word mask by allowing input
data to be wri tten if it is low but blocks th e write oper ation if is high for x 16 LDM
corresponds to data on DQ0-DQ 7, UDM cor r esponds to data on DQ8 - DQ15.
QFC
Output Level Active Low FET Control: Output during every read and write access. Can be used to control isolation
switches on modules.
VDD, VSS Supply Power an d gr ound for the input bu ff ers and the core logic .
VDDQ
VSSQ
Supply — — Isolated power supply and ground for the output buffers to provide improved noise
immunity.
VREF Input Lev el — SS TL Reference Volt ag e for Input s
8
V58C2256(804/404/164)S Rev. 1.4 October 2002
MOSEL VITELIC
V58C2256(804/404/164)S
Mode Register Set (MRS)
The mode register stores the data for controlling the various operating modes of DDR SDRAM. It programs
CAS
latency, addressing mode, burst length, test mode, DLL reset and various vendor specific options to
make DDR SDRAM useful for a variety of different applicati ons. The default value of the mode register is not
defined, therefore the mode register must be written after EMRS setting for proper DDR SDRAM operation.
The mode register is written by asserting low on CS
, RAS, CAS, WE and BA0 (The DDR SDRAM should be
in all bank precharge with CKE already high prior to writing into the mode register). The state of address pins
A
0
~ A12 in the same cycle as CS, RAS, CAS, WE and BA0 low is written in the mode reg ister. Two cl ock
cycles are required to meet t
MRD
spec. The mode register contents can be changed us ing the same command and clock cycle requirements during operation as long as all banks are in the idle state. The mode register is divided into various fields depending on functionality. The burst length uses A
0
~ A2, addressing mode
uses A
3
, CAS latency (read latency from column address) uses A4 ~ A6. A7 is a Mosel Vit elic spe cific tes t
mode during production test. A
8
is used for DLL reset. A7 must be set to low for normal MRS operation. Refer
to the table for specific codes for various burst length, addressing modes and CAS
latencies .
1. MRS can be issued only at all banks precharge state.
2. Minimum tRP is required to issue MRS command.
Address Bus
CAS
Latency
A6A5A
4
Latency
0 0 0 Reserve
0 0 1 Reserve
01 0 2
01 1 3
1 0 0 Reserve
Reserve
10 1
1 1 0 2.5
1 1 1 Reserve
Burst Length
A2A1A
0
Latency
Sequential Interleave
0 0 0 Reserve Reserve
001 2 2
010 4 4
011 8 8
1 0 0 Reserve Reserve
1 0 1 Reserve Reserve
1 1 0 Reserve Reserve
1 1 1 Reserve Reserve
A
7
mode
0
Normal
1
Test
A3Burst Type
0 Sequential
1 Interleave
* RFU(Reserved for future use)
should stay "0" during MRS
cycle.
A
8
DLL Reset
0No
1 Yes
Mode Register Set
0 RFU : Must be set "0"
Extended Mode Register
Mode Register
DLLI/OQFC
A0DLL Enable
0 Enable
1 Disable
A2QFC Contro
l
0 Disable
1 Enable
A1I/O Strength
0 Full
1 Half
BA
0
An ~ A
0
0 (Existing)MRS Cycle
1 Extended Funtions(EMRS)
Command
201 534 867
CK, CK
t
CK
t
MRD
Precharge
All Banks
Mode
Register Set
t
RP
*2
*1
Any
Command
BA1BA
0
A
3
A2A1A
0
0TM
CAS Latency
BT Burst LengthRFU DLL
MRS
MRS
A
12
to
9
MOSEL VITELIC
V58C2256(804/404/164)S
V58C2256(804/404/164)S Rev. 1.4 October 2002
Mode Register Set Timing
Burst Mode Operation
Burst Mode Operation i s used to pro vide a consta nt flow of data to memory loca tions (Write cycle), or from
memory locations (Read cycle). Two parameters define how the burst mode will operate: burst sequence and
burst length. These p arameters are programma ble and are determined by a ddress bits A
0—A3
during the
Mode Register Set command. B urst t ype defi nes the sequence in whic h the burst data will be delivered or
stored to the SDRA M. Two types of burst sequenc e are supported: sequential and interlea ve. The burst
length controls the number of bits that will be output after a Read command, or the number of bits to be input
after a Write command. The burst length can be programmed to values of 2, 4, or 8. See the Burst Length
and Sequence table below for programming information.
Burst Length and Sequence
Burst Length Starting Length (A2, A1, A0) Sequential Mode Interleave Mode
2
xx0 0, 1 0, 1
xx1 1, 0 1, 0
4
x00 0, 1, 2, 3 0, 1, 2, 3
x01 1, 2, 3, 0 1, 0, 3, 2
x10 2, 3, 0, 1 2, 3, 0, 1
x11 3, 0, 1, 2 3, 2, 1, 0
8
000 0,1, 2, 3, 4, 5, 6, 7 0,1, 2, 3, 4, 5, 6, 7
001 1, 2, 3, 4, 5, 6, 7, 0 1, 0, 3, 2, 5, 4, 7, 6
010 2, 3, 4, 5, 6, 7, 0, 1 2, 3, 0, 1, 6, 7, 4, 5
011 3, 4, 5, 6, 7, 0, 1, 2 3, 2, 1, 0, 7, 6, 5, 4
100 4, 5, 6, 7, 0, 1, 2, 3 4, 5, 6, 7, 0, 1, 2, 3
101 5, 6, 7, 0, 1, 2, 3, 4 5, 4, 7, 6, 1, 0, 3, 2
110 6, 7, 0, 1, 2, 3, 4, 5 6, 7, 4, 5, 2, 3, 0, 1
111 7, 0, 1, 2, 3, 4, 5, 6 7, 6, 5, 4, 3, 2, 1, 0
T5T0 T1 T2 T3 T4 T6 T7 T8
t
RP
t
MRD
t
CK
Pre- All
MRS/EMRS
ANY
M
ode Register set (MRS) or Extended Mode Register Set (EMRS) can be issued only when all banks are in the idle state.
CK,
CK
Command
I
f a MRS command is issued to reset the DLL, then an additional 200 clocks must occur prior to issuing any new command
T9
t
o allow time for the DLL to lock onto the clock.
10
V58C2256(804/404/164)S Rev. 1.4 October 2002
MOSEL VITELIC
V58C2256(804/404/164)S
Bank Activate Command
The Bank Activate command is issued by holding CAS and WE high with CS and RAS low at the rising
edge of the clock. The DDR SDRA M ha s four ind epende nt banks, so t wo Bank Select addresses (BA
0
and
BA
1
) are supported. The Bank Activate command must be applied before any Read or Write operation can
be executed. The delay from the B ank Activat e comm and to t he first Read or Write com ma nd mu st m eet or
exceed the minimum RAS
to CAS delay time (t
RCD
min). Once a bank has be en activated, it must be precharged before another Bank Activate command can be applied to the same bank. The minimum time interval
between interleaved Bank Activate commands (Bank A to Bank B and vice versa) is the Bank to Bank delay
time (t
RRD
min).
Bank Activation Timing
Read O p er ati o n
With the DLL enabled, al l devices operat ing at the same frequenc y within a system are ensured t o have
the same timing relationship between DQ and DQS relative to the CK input regardless of device density, process variation, or technology generation.
The data strobe signal (DQS) is driven off chip simultaneously with the output data (DQ) during each read
cycle. The same internal clock phase is used to drive both the output data and data strobe signal off chip to
minimize skew between d ata strobe and o utput data. This internal clock phase is nominally aligned t o the
input differential clock (CK, CK
) by the on-chip DLL. Therefore, when the DLL is enabled and the clock frequency is within the specified range for proper DLL operation, the data strobe (DQS), output data (DQ), and
the system clock (CK) are all nominally aligned.
Since the data strobe and output data are tightly coupled in the system, the data strobe signal may be delayed and used to latch the output data into the receiving device. The tolerance for skew between DQS and
DQ (t
DQSQ
) is tighter than that possible for CK to DQ (tAC) or DQS to CK (t
DQSCK
).
T0 T1 T2 T3 Tn Tn+1 Tn+2 Tn+3 Tn+4 Tn+5
(CAS Latency = 2; Burst Length = Any)
t
RRD
(min)tRP(min)
t
RC
t
RCD
(min)
Begin Precharge Bank A
CK,
CK
B
A/Address
Command
Bank/Col
Read/A
Bank/Row
Activate/A Activate/B
Pre/A
Bank/Row
Activate/A
Bank
Bank/Row
t
RAS
(min)
11
MOSEL VITELIC
V58C2256(804/404/164)S
V58C2256(804/404/164)S Rev. 1.4 October 2002
Output Data (DQ) and Data Strobe (DQS) Timing Relative to the Clock (CK)
During Read Cycles
The minimum time during which the output data (DQ) is valid is critical f or the receiving device (i .e., a memory controller device). This al so applies to the data strobe durin g t he read c ycle s ince it is t ightly coupled to
the output data. The minimum data output valid time (t
DV
) and minimum data strobe valid time (t
DQSV
) are derived from the minimum clock high/low time minus a margin for variation in data access and hold time due to
DLL jitter and power supply noise.
(CAS Latency = 2.5; Burst Length = 4
)
T0 T1 T2 T3 T4
NOP NOPNOP
D
0
CK, CK
C
ommand
DQS
DQ
D
2
t
DQSCK
(max)
t
DQSCK
(min)
D
1
tAC(min)
tAC(max)
D
3
READ NOP
12
V58C2256(804/404/164)S Rev. 1.4 October 2002
MOSEL VITELIC
V58C2256(804/404/164)S
Output Data and Data Strobe Valid Window for DDR Read Cycles
Read Preamble and Po stamble O peration
Prior to a burst of read data and given that the controller is not currently in burst read mode, the data strobe
signal (DQS), must transition from Hi-Z to a valid logic low. The is referred to as the data strobe “read preamble” (t
RPRE
). This transition from Hi-Z to logic low nominally happens one clock cycle prior to the first edge of
valid data.
Once the burst of read data is concluded and given that no subsequent burst read operations are initiated,
the data strobe signal (DQS) transitions from a logic low lev el back to Hi-Z. This is referred to as the data
strobe “read postamble” (t
RPST
). This transition happens nominally one-half clock period after the last edge of
valid data.
Consecutive or “gapless” burst read operations are possible from the same DDR SDRAM device with no
requirement for a data strobe “read” preamble o r postamble in be tween the groups of burst data. The da ta
strobe read preamble is required before the DDR d evice drives the first output data off chip. Similarly, the
data strobe po stambl e i s i nit iated wh en the d evi ce s tops driv ing DQ data at t he t er minati on of read b ur st cy cle s.
D
0
D
1
(CAS Latency = 2; Burst Length = 2)
T0 T1 T2 T3 T4
READ NOP NOPNOP
C
ommand
DQS
DQ
tDV(min)
CK, CK
t
DQSV
(min)
13
MOSEL VITELIC
V58C2256(804/404/164)S
V58C2256(804/404/164)S Rev. 1.4 October 2002
Data Strobe Preamble and Postamble Timings for DDR Read Cycles
Consecutive Burst Read Operation and Effects on the Dat a Strobe Preamble and Posta mble
(CAS Latency = 2; Burst Length = 2)
T0 T1 T2 T3 T4
READ NOP NOPNOP
D
0
D
1
CK, CK
C
ommand
DQS
DQ
t
RPRE
(max)
t
RPST
(min)
t
RPRE
(min)
t
RPST
(max)
t
DQSQ
(max)
t
DQSQ
(min)
NOP Read
B
NOP NOP NOP NOPRead
A
D0AD1
A
NOP
D2
AD3A
Command
DQS
DQ
Burst Read Operation (CAS Latency = 2; Burst Length = 4)
CK, CK
NOP
D0BD1BD2BD3
B
NOP Read
B
NOP NOP NOP NOPRead
A
D0AD1
A
NOP
D2
AD3A
Command
DQS
DQ
Burst Read Operation (CAS Latency = 2; Burst Length = 4)
CK, CK
NOP
D0BD1BD2BD3
B
14
V58C2256(804/404/164)S Rev. 1.4 October 2002
MOSEL VITELIC
V58C2256(804/404/164)S
Auto Pr ech arge Oper ati o n
The Auto Precharge operation can be issu ed by having column address A10 high when a Read or Write
command is issued. If A
10
is low when a Read or Write command is issued, then normal Read or Write burst
operation is executed and the b ank rema ins active at the com pletion of the burst sequence. When the Auto
Precharge command is act ivated, the ac tive bank autom at ically beg ins to p recharge at the earliest possible
moment during the Read or Write cycle once t
RAS
(min) is satisfied.
Read with Auto Precharge
If a Read with Auto Precharge comm and is i nitiated, the DDR SDRAM will enter the precharge operation
N-clock cycles measured from the last data of the burst read cycle where N is equal to the CAS
latency programmed into the device. Once the autoprecharge operation has begun, the bank cannot be reactivated until
the minimum precharge time (t
RP
) has been satisfied.
Read with Autoprecharge Timing
(CAS Latency = 2; Burst Length =
4)
T0 T1 T2 T3 T4 T5 T6 T7 T8
D0D1D2D
3
Begin Autoprecharge
BAACT R w/AP NOPNOP NOP NOP NOP
NOP
CK,
CK
C
ommand
DQS
DQ
t
RAS
(min)
t
P
(min)
Earliest Bank A reactivate
T9
15
MOSEL VITELIC
V58C2256(804/404/164)S
V58C2256(804/404/164)S Rev. 1.4 October 2002
Read with Autoprecharge Timing as a Function of CAS Latency
T0 T1 T2 T3 T4 T5 T6 T7 T8
NOPRAP NOPNOP NOP NOP BA NOP
CK,
CK
C
ommand
DQS
DQ
t
RAS
(min)
tRP(min)
BA NOP
T9
D0D1D2D
3
DQS
DQ
CAS Latency=2
CAS Latency=2.5
(CAS Latency = 2, 2.5, Burst Length = 4)
D
0D1D2D3
16
V58C2256(804/404/164)S Rev. 1.4 October 2002
MOSEL VITELIC
V58C2256(804/404/164)S
Precharge Timing During Re ad Operati on
For the earliest possible Precharge command without interrupting a Read burst, the Precharge command
may be issued on the rising clock edge which is CAS
latency (CL) clock cycles before the end of the Read
burst. A new Bank Activate (BA) com mand may be issued to the sam e bank after the RAS
precharge time
(t
RP
). A Precharge command can not be issued until t
RAS
(min) is satisfied.
Read with Precharge Timing as a Function of CAS Latency
T0 T1 T2 T3 T4 T5 T6 T7 T8
D0D1D2D
3
NOPRead NOPNOP Pre
A
NOP BA NOP
CK,
CK
C
ommand
DQS
DQ
t
RAS
(min)
tRP(min)
BA NOP
T9
D0D1D2D
3
DQS
DQ
CAS Latency=2
CAS Latency=2.5
(CAS Latency = 2, 2.5, 3; Burst Length = 4)
17
MOSEL VITELIC
V58C2256(804/404/164)S
V58C2256(804/404/164)S Rev. 1.4 October 2002
Burst Stop Command
The Burst Stop command is valid only during burst read cycles and is initiated by having RAS and CAS
high with CS and WE l ow at the rising edge of the c lock. When th e B urst Stop comm and is i ssue d durin g a
burst Read cycle, both the output data (DQ) and data strobe (DQS) go to a high impedance state after a delay
(L
BST
) equal to the CAS latency programmed into t he device. If the Burst Stop command is issued during a
burst Write cycle, the command will be treated as a NOP command.
Read Terminated by Burst Stop Command Timing
(CAS Latency = 2, 2.5, 3; Burst Length =
4)
T0 T1 T2 T3 T4 T5 T6
BST NOP NOP NOP NOPRead
D
0D1
CK, CK
Command
DQS
DQ
D0D
1
DQS
DQ
C
AS Latency = 2
C
AS Latency = 2.5
L
BST
L
BST
L
BST
18
V58C2256(804/404/164)S Rev. 1.4 October 2002
MOSEL VITELIC
V58C2256(804/404/164)S
Read Interrupted by a Precharge
A Burst Read operation can be interrupted by a precharge of the same bank. The Precharge command to
Output Disable latency is equivalent to the CAS
latency.
Read Interrupted by a Precharge Timing
Burst W r it e Op eration
The Burst Write command is issued by having CS, CAS, and WE low while holding RAS high at the rising
edge of the clock. The address inputs determine the starting column address. The memory controller is required to provide an input data strobe (DQS) to the DDR S DRAM to strob e or latch the input data (DQ) and
data mask (DM) into the device. During Write cycles, t he data str obe applied to the DDR S DRAM is required
to be nominally centered within the data (DQ) and data mask (DM) valid windows. The data strobe mu st be
driven high nominally one clock after the write command has been registered. Timing parameters t
DQSS
(min)
and t
DQSS
(max) define the allowable window when the data strobe must be driven high.
Input data for the first Burst Write cycle must be applied one clock cycle after the Write command is
registered into the device (WL=1). The input data valid window is nominally centered around the midpoint of
the data strobe signal. The data window is defined by DQ to DQS s etup time (t
QDQSS
) and DQ to DQS hold
time (t
QDQSH
). All data inputs must be supplied on each rising and falling edge of the data strobe until the burst
length is completed. When the burst has finished, any additional data supplied to the DQ pins will be ignored.
Write Preamble and Postamb le Operati on
Prior to a burst of write data and given that the controller is not currently in burst write mode, the data strobe
signal (DQS), must transition from Hi-Z to a valid logic low. This is referred to as the data strobe “write preamble”.
This transit ion f rom H i-Z to logic low nominally happens on the falling edge of the c lock af ter the wr ite c ommand has been registered by the device. The preamble is explicitly defined by a setup time (t
WPRES
(min)) and
hold time (t
WPREH
(min)) referenced to the first falling edge of CK after the write command.
T0 T1 T2 T3 T4 T5 T6 T7 T8
D0D1D2D
3
NOPRead NOPNOP Pre
A
NOP BA NOP
CK,
CK
C
ommand
DQS
DQ
t
RAS
(min)
tRP(min)
BA NOP
T9
D0D1D2D
3
DQS
DQ
CAS Latency=2
CAS Latency=2.5
(CAS Latency = 2, 2.5, 3; Burst Length =
8)
19
MOSEL VITELIC
V58C2256(804/404/164)S
V58C2256(804/404/164)S Rev. 1.4 October 2002
Burst Write Timing
Once the burst of write data is concluded and given that no subsequent burst write operations are initiated,
the data strobe signal (DQS) transitions from a logic low lev el back to Hi-Z. This is referred to as the data
strobe “write postamble”. This transition happens nom inally one-half clock period after the last dat a of the
burst cycle is latched into the device.
(CAS Latency = Any; Burst Length =
4)
T0 T1 T2 T3 T4
WRITE NOP NOPNOP
D
0
D
1
D
2
D
3
CK, CK
C
ommand
D
QS(nom)
DQ(nom)
t
WPRES
t
WPREH
t
DQSS
t
WPST
t
QDQSH
D
0
D
1
D
2
D
3
DQS(min)
DQ(min)
t
DQSS
(min)
D
0
D
1
D
2
D
3
D
QS(max)
DQ(max)
t
WPRES
(min)
t
DQSS
(max)
t
QDQSS
t
QDQSS
t
QDQSH
t
WPREH
(min)
t
WPREH
(max)
t
WPRES
(max)
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