System Frequency (f
Clock Cycle Time (t
Clock Cycle Time (t
Clock Cycle Time (t
Features
4 banks x 2Mbit x 8 organization
High speed data transfer rates with system
frequency up to 166 MHz
Data Mask for Write Control (DM)
Four Banks controlled by BA0 & BA1
Programmable CAS
■
Programmable Wrap Sequence: Sequential
or Interleave
■
Programmable Burst Length:
2, 4, 8 for Sequential Type
2, 4, 8 for Interleave Type
■
Automatic and Controlled Precharge Command
■
Suspend Mode and Power Down Mode
■
Auto Refresh and Self Refresh
■
Refresh Interval: 4096 cycles/64 ms
■
Available in 66-pin 400 mil TSOP-II
■
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
CLK transitions
■
Differential clock inputs CLK and CLK
Power Supply 2.5V ± 0.2V
)166 MHz143 MHz125 MHz
CK
)6 ns7 ns8 ns
CK3
)6.5 ns7.5 ns9 ns
CK2.5
)7ns8ns10ns
CK2
Latency: 2, 2.5, 3
PRELIMINARY
678
Description
The V58C265804S is a four bank DDR DRAM organized as 4 banks x 2Mbit x 8. The V58C265804S
achieves high speed data transfer rates by employing a chip architecture that prefetches multiple 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 possible on both
edges of DQS.
Operating the four memory banks in an interleaved fashion allows random access 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
speed grade of the device.
latency and
Device Usage Chart
Operating
Temperature
Range
C to 70 °C••••••Blank
V58C265804S Rev. 1.3 January 2000
Package OutlineCLK Cycle Time (ns)Power
Temperature
MarkJEDEC 66 TSOP II–6-7-8Std.L
1
MOSEL VITELIC
66 Pin Plastic TSOP-II
PIN CONFIGURATION
Top View
DD
NC
NC
NC
NC
NC
NC
NC
DD
NC
NC
CS
NC
A0
A1
A2
A3
DD
1
2
0
3
4
5
1
6
7
8
2
9
10
11
3
12
13
14
15
DDR SDRAM
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
V
DQ
V
DDQ
DQ
V
SSQ
DQ
V
DDQ
DQ
V
SSQ
V
DDQ
V
WE
CAS
RAS
BA0
BA1
A10/AP
V
64M
66
65
64
63
62
61
60
59
58
57
56
55
54
53
52
51
50
49
48
47
46
45
44
43
42
41
40
39
38
37
36
35
34
V
SS
DQ
V
SSQ
NC
DQ
V
DDQ
NC
DQ
V
SSQ
NC
DQ
V
DDQ
NC
NC
V
SSQ
DQS
NC
V
REF
V
SS
DM
CLK
CLK
CKE
NC
NC
A11
A9
A8
A7
A6
A5
A4
V
SS
V58C265804S
Pin Names
CLK, CLK
CKEClock Enable
CSChip Select
7
RASRow Address Strobe
CASColumn Address Strobe
6
WEWrite Enable
DQSData Strobe (Bidirectional)
5
A
–A
0
11
BA0, BA1Bank Select
DQ
4
–DQ
0
7
DMData Mask
V
DD
V
SS
V
DDQ
V
SSQ
NCNot connected
VREFReference Voltage for Inputs
Differential Clock Input
Address Inputs
Data Input/Output
Power (+2.5V)
Ground
Power for I/O’s (+2.5V)
Ground for I/O’s
V58C265804S Rev. 1.3 January 2000
2
*
MOSEL VITELIC
Capacitance*
T
= 0 to 70°C, V
A
Symbol Parameter
C
I1
C
I2
C
IO
C
CLK
Note:Capacitance is sampled and not 100% tested.
Input Capacitance (A0 to A11)5pF
Input Capacitance
Operating temperature range..................0 to 70 °C
Storage temperature range................-55 to 150 °C
Input/output voltage.................. -0.3 to (V
Power supply voltage.......................... -0.3 to 4.6 V
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 device reliability.
Row Addresses
A0 - A11, BA0, BA1A0 - A8, AP, BA0, BA1
Row address
buffer
Refresh Counter
+0.3) V
CC
Row decoder
Memory array
Bank 0
4096 x 512
Column decoder
Sense amplifier & I(O) bus
x 8 bit
CLK, CLK
DQS
Row decoder
Memory array
Bank 1
4096 x 512
Column decoder
Sense amplifier & I(O) bus
DLL
Strobe
Gen.
x 8 bit
Input bufferOutput buffer
-DQ
DQ
0
Data Strobe
Row decoder
Memory array
Bank 2
4096 x 512
Column decoder
Sense amplifier & I(O) bus
x 8 bit
7
Row decoder
Memory array
Bank 3
4096 x 512
CKE
CS
x 8 bit
RAS
CAS
WE
Column decoder
Sense amplifier & I(O) bus
Control logic & timing generator
CLK
CLK
DM
V58C265804S Rev. 1.3 January 2000
3
MOSEL VITELIC
V58C265804S
Signal Pin Description
PinTypeSignalPolarityFunction
CLK
CLK
CKEInputLevelActive High Activates the CLK signal when high and deactivates the CLK signal when low, thereby
CSInputPulseActive Low CS enables the command decoder when low and disables the command decoder when
RAS, CAS WEInputPulseActive Low When sampled at the positive rising edge of the clock, CAS, RAS, and WE define the
DQSInput/
A0 - A11InputLevel—During a Bank Activate command cycle, A0-A11 defines the row address (RA0-RA11)
InputPulsePositive
Edge
PulseActive High Active on both edges for data input and output.
Output
The system clock input. All inputs except DQs and DMs are sampled on the rising edge
of CLK.
initiates either the Power Down mode, Suspend mode, or the Self Refresh mode.
high. When the command decoder is disabled, new commands are ignored but previous
operations continue.
command to be executed by the SDRAM.
Center aligned to input data
Edge aligned to output data
when sampled at the rising clock edge.
During a Read or Write command cycle, A0-An defines the column address (CA0-CAn)
when sampled at the rising clock edge.CAn depends from the SDRAM organization:
8M x 8 SDRAM CAn = CA8 (Page Length = 512 bits)
In addition to the column address, A10(=AP) is used to invoke autoprecharge operation
at the end of the burst read or write cycle. If A10 is high, autoprecharge is selected and
BA0, BA1 defines the bank to be precharged. If A10 is low, autoprecharge is disabled.
During a Precharge command cycle, A10(=AP) is used in conjunction with BA0 and BA1
to control which bank(s) to precharge. If A10 is high, all four banks will be precharged
simultaneously regardless of state of BA0 and BA1.
BA0,
BA1
DQxInput/
DM InputPulseActive High In Write mode, DM has a latency of zero and operates as a word mask by allowing input
VDD, VSS SupplyPower and ground for the input buffers and the core logic.
VDDQ
VSSQ
VREFInputLevel—SSTL Reference Voltage for Inputs
InputLevel—Selects which bank is to be active.
Level—Data Input/Output pins operate in the same manner as on conventional DRAMs.
Output
data to be written if it is low but blocks the write operation if is high.
Supply——Isolated power supply and ground for the output buffers to provide improved noise
immunity.
V58C265804S Rev. 1.3 January 2000
4
■
MOSEL VITELIC
V58C265804S
Functional Description
Power-Up Sequence
The following sequence is required for POWER UP.
1. Apply power and attempt to maintain CKE at a low stately other inputs may be undefined.)
- Apply VDD before or at the same time as VDDQ.
- Apply VDDQ before or at the same time as VTT & Vref.
2. Start clock and maintain stable condition for a minimum of 200us.
3. The minimum of 200us after stable power and clock (CLK, CLK
4. Precharge all banks.
5. Issue EMRS to enable DLL.(To issue “DLL Enable” command, provide “Low” to A0, “High” to BA0
and “Low” to all of the rest address pins, A1~A11 and BA1)
6. Issue a mode register set command for “DLL reset”. The additional 200 cycles of clock input is
required to lock the DLL. (To issue DLL reset command, provide “High” to A8 and “Low” to BA0)
7. Issue precharge commands for all banks of the device.
8. Issue 2 or more auto-refresh commands.
9. Issue a mode register set command to initialize device operation.
Note1 Every “DLL enable” command resets DLL. Therefore sequence 6 can be skipped during power up. Instead of it,
the additional 200 cycles of clock input is required to lock the DLL after enabling DLL.
), apply NOP & take CKE high.
Power up Sequence & Auto Refresh(CBR)
0
12345678910111213141516171819
CK, CK
Command
••
200 µS Power up
to 1st command
precharge
ALL Banks
2 Clock min.
EMRS
precharge
ALL Banks
tRP
1st Auto
Refresh
2 Clock min.
MRS
DLL Reset
min. 200 Cycle
654788
tRFC
••••
••
••
2nd Auto
Refresh
tRFC
••
••
••
Mode
Register Set
2 Clock min.
Any
Command
Extended Mode Register Set (EMRS)
The extended mode register stores the data for enabling or disabling DLL. The default value of the extended mode register is not defined, therefore the extended mode register must be written after power up for enabling or disabling DLL. The extended mode register is written by asserting low on CS
high on BA
the extended mode register). The state of address pins A
(The DDR SDRAM should be in all bank precharge with CKE already high prior to writing into
0
~ A
0
and BA
11
in the same cycle as CS
1
CAS and WE low is written in the extended mode register. Two clock cycles are required to complete the
write operation in the extended mode register. The mode register contents can be changed using the same
command and clock cycle requirements during operation as long as all banks are in the idle state. A
for DLL enable or disable. “High” on BA
must be set to low for proper EMRS operation. A
A
= 1 half strength. Refer to the table for specific codes.
1
is used for EMRS. All the other address pins except A
0
is used at EMRS to indicate I/O strength A
1
, RAS, CAS, WE and
, RAS,
is used
0
and BA
0
= 0 full strength,
1
0
V58C265804S Rev. 1.3 January 2000
5
MOSEL VITELIC
V58C265804S
Mode Register Set (MRS)
The mode register stores the data for controlling the various operating modes of DDR SDRAM. It programs
latency, addressing mode, burst length, test mode, DLL reset and various vendor specific options to
CAS
make DDR SDRAM useful for a variety of different applications. 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 BA
in all bank precharge with CKE already high prior to writing into the mode register). The state of address pins
A
~ A
0
in the same cycle as CS
11
cycles are required to meet t
, RAS, CAS, WE and BA0 low is written in the mode register. Two clock
spec. The mode register contents can be changed using the same com-
MRD
mand 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
uses A
3
mode during production test. A
latency (read latency from column address) uses A
, CAS
is used for DLL reset. A
8
~ A
must be set to low for normal MRS operation. Refer
7
4
to the table for specific codes for various burst length, addressing modes and CAS
1.MRS can be issued only at all banks precharge state.
Mode Register set (MRS) or Extended Mode Register Set (EMRS) can be issued only when all banks are in the idle state.
If a MRS command is issued to reset the DLL, then an additional 200 clocks must occur prior to issuing any new command
to allow time for the DLL to lock onto the clock.
Pre- AllMRS/EMRSANY
t
RP
t
MRD
T9
Burst Mode Operation
Burst Mode Operation is used to provide a constant flow of data to memory locations (Write cycle), or from
memory locations (Read cycle). Two parameters define how the burst mode will operate: burst sequence and
burst length. These parameters are programmable and are determined by address bits A
Mode Register Set command. Burst type defines the sequence in which the burst data will be delivered or
stored to the SDRAM. Two types of burst sequence are supported: sequential and interleave. 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.
The Bank Activate command is issued by holding CAS
edge of the clock. The DDR SDRAM has four independent banks, so two Bank Select addresses (BA0 and
BA1) are supported. The Bank Activate command must be applied before any Read or Write operation can
be executed. The delay from the Bank Activate command to the first Read or Write command must meet or
exceed the minimum RAS to CAS delay time (t
RCD
charged 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).
and WE high with CS and RAS low at the rising
min). Once a bank has been activated, it must be pre-
Bank Activation Timing
(CAS Latency = 2; Burst Length = Any)
T0T1T2T3TnTn+1Tn+2Tn+3Tn+4Tn+5
t
CK,
CK
BA/Address
Command
Bank/Row
Activate/A
t
RAS
t
RCD
(min)
(min)
Bank/Col
Read/A
RC
Bank
Pre/A
Bank/Row
Activate/AActivate/B
t
RRD
(min)tRP(min)
Bank/Row
Begin Precharge Bank A
Read Operation
With the DLL enabled, all devices operating at the same frequency within a system are ensured to 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 data strobe and output data. This internal clock phase is nominally aligned to 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
) is tighter than that possible for CK to DQ (tAC) or DQS to CK (t
DQSQ
DQSCK
).
V58C265804S Rev. 1.3 January 2000
8
MOSEL VITELIC
Output Data (DQ) and Data Strobe (DQS) Timing Relative to the Clock (CK)
T0T1T2T3T4
CK, CK
V58C265804S
During Read Cycles
(CAS Latency = 2.5; Burst Length = 4)
Command
DQS
DQ
READNOP
t
DQSCK
t
AC
NOPNOPNOP
t
(max)
DQSCK
t
(min)
DQSCK
tAC(min)
D
0
D
1
D
2
tAC(max)
D
3
The minimum time during which the output data (DQ) is valid is critical for the receiving device (i.e., a memory controller device). This also applies to the data strobe during the read cycle since it is tightly coupled to
the output data. The minimum data output valid time (tDV) 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.
V58C265804S Rev. 1.3 January 2000
9
MOSEL VITELIC
Output Data and Data Strobe Valid Window for DDR Read Cycles
T0T1T2T3T4
CK, CK
V58C265804S
(CAS Latency = 2; Burst Length = 2)
Command
DQS
DQ
READNOPNOPNOP
t
DQSV
tDV(min)
(min)
D
0
D
1
Read Preamble and Postamble Operation
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
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 level back to Hi-Z. This is referred to as the data
strobe “read postamble” (t
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 or postamble in between the groups of burst data. The data
strobe read preamble is required before the DDR device drives the first output data off chip. Similarly, the
data strobe postamble is initiated when the device stops driving DQ data at the termination of read burst cycles.
). This transition from Hi-Z to logic low nominally happens one clock cycle prior to the first edge of
RPRE
). This transition happens nominally one-half clock period after the last edge of
RPST
V58C265804S Rev. 1.3 January 2000
10
MOSEL VITELIC
Data Strobe Preamble and Postamble Timings for DDR Read Cycles
T0T1T2T3T4
CK, CK
V58C265804S
(CAS Latency = 2; Burst Length = 2)
Command
READNOPNOPNOP
t
(min)
RPRE
t
RPRE
(max)
t
RPST
(min)
DQS
t
(max)
RPST
DQ
t
DQSQ
(min)
D
0
t
DQSQ
D
1
(max)
Consecutive Burst Read Operation and Effects on the Data Strobe Preamble and Postamble
The Auto Precharge operation can be issued by having column address A10 high when a Read or Write
command is issued. If A10 is low when a Read or Write command is issued, then normal Read or Write burst
operation is executed and the bank remains active at the completion of the burst sequence. When the Auto
Precharge command is activated, the active bank automatically begins to precharge at the earliest possible
moment during the Read or Write cycle once t
(min) is satisfied.
RAS
Read with Auto Precharge
If a Read with Auto Precharge command is initiated, 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. If a Read with autoprecharge command is issued before t
precharge operation will be delayed until that time when t
(min) is met. Once the autoprecharge opera-
RAS
(min) is satisfied, the
RAS
tion has begun, the bank cannot be reactivated until the minimum precharge time (tRP) has been satisfied.
Read with Autoprecharge Timing
(CAS Latency = 2; Burst Length = 4)
CK, CK
Command
DQS
DQ
T0T1T2T3T4T5T6T7T8
t
RAS
(min)
D0D1D2D
Begin Autoprecharge
tRP(min)
3
Earliest Bank A reactivate
T9
NOPBAR w/APNOPNOPNOPNOPNOPBA
V58C265804S Rev. 1.3 January 2000
12
MOSEL VITELIC
Read with Autoprecharge Timing as a Function of CAS Latency
V58C265804S
(CAS Latency = 2, 2.5, 3; Burst Length = 4)
CK,
CK
Command
DQS
DQ
DQS
DQ
DQS
DQ
T0T1T2T3T4T5T6T7T8
t
BANOP
RAS
(min)
Begin Autoprecharge
tRP(min)
D
0D1D2D3
1
CAS Latency=2
D0D1D2D
CAS Latency=2.5
D0D1D2D
CAS Latency=3
3
3
T9
NOPRAPNOPNOPNOPNOPBANOP
V58C265804S Rev. 1.3 January 2000
13
MOSEL VITELIC
V58C265804S
Precharge Timing During Read Operation
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) command may be issued to the same bank after the RAS precharge time
(tRP). A Precharge command can not be issued until t
(min) is satisfied.
RAS
Read with Precharge Timing as a Function of CAS Latency
(CAS Latency = 2, 2.5, 3; Burst Length = 4)
CK
CK,
Command
DQS
DQ
DQS
DQ
DQS
DQ
T0T1T2T3T4T5T6T7T8
t
BANOP
RAS
(min)
tRP(min)
NOPBANOP
A
D0D1D2D
CAS Latency=2
D0D1D2D
CAS Latency=2.5
D0D1D2D
CAS Latency=3
3
3
3
T9
NOPReadNOPNOPPre
V58C265804S Rev. 1.3 January 2000
14
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