256Mb: x4, x8, x16 DDR SDRAM
Features
Double Data Rate (DDR) SDRAM
MT46V64M4 – 16 Meg x 4 x 4 banks
MT46V32M8 – 8 Meg x 8 x 4 banks
MT46V16M16 – 4 Meg x 16 x 4 banks
Features
• V
DD
= +2.5V ±0.2V, V
DD
Q = +2.5V ±0.2V
• V
DD
= +2.6V ±0.1V, V
DD
Q = +2.6V ±0.1V (DDR400)
• Bidirectional data strobe (DQS) transmitted/
received with data, i.e., source-synchronous data
capture (x16 has two – one per byte)
• Internal, pipelined double-data-rate (DDR)
architecture; two data accesses per clock cycle
• Differential clock inputs (CK and CK#)
• Commands entered on each positive CK edge
• DQS edge-aligned with data for READs; center-
aligned with data for WRITEs
• DLL to align DQ and DQS transitions with CK
• Four internal banks for concurrent operation
• Data mask (DM) for masking write data (x16 has two
– one per byte)
• Programmable burst lengths: 2, 4, or 8
• Auto Refresh and Self Refresh Modes
• Longer-lead TSOP for improved reliability (OCPL)
• 2.5V I/O (SSTL_2 compatible)
• Concurrent auto precharge option supported
•
t
RAS lockout supported (
t
RAP =
t
RCD)
For the most current data sheet, please refer to the Micron
®
Web site:
www.micron.com/datasheets
Options
• Configuration
64 Meg x 4 (16 Meg x 4 x 4 banks)
32 Meg x 8 (8 Meg x 8 x 4 banks)
16 Meg x 16 (4 Meg x 16 x 4 banks)
• Plastic Package – OCPL
66-pin TSOP
66-pin TSOP (lead-free)
• Plastic Package
60-Ball FBGA (8mm x 14mm)
60-Ball FBGA (8mm x 14mm) lead-free
• Timing – Cycle Time
5ns @ CL = 3 (DDR400B)
6ns @ CL = 2.5 (DDR333) FBGA only
6ns @ CL = 2.5 (DDR333) TSOP only
7.5ns @ CL = 2 (DDR266)
7.5ns @ CL = 2 (DDR266A)
7.5ns @ CL = 2.5 (DDR266B)
• Self Refresh
Standard
Low-Power Self Refresh
• Temperature Rating
Commercial (0°C to +70°C)
Industrial (-40°C to +85°C)
• Revision
x4, x8
x16
32 Meg x 8
8 Meg x 8 x 4 banks
8K
8K (A0–A12)
4 (BA0,BA1)
1K (A0–A9)
Marking
64M4
32M8
16M16
TG
P
FG
BG
-5B
-6
-6T
-75E
-75Z
-75
None
L
None
IT
:G, :C
:C, :F
Table 1:
Configuration Addressing
64 Meg x 4
16 Meg x 4 x 4 banks
8K
8K (A0–A12)
4 (BA0,BA1)
2K (A0–A9,A11)
16 Meg x 16
4 Meg x 16 x 4 banks
8K
8K (A0–A12)
4 (BA0,BA1)
512 (A0–A8)
Configuration
Refresh Count
Row Addressing
Bank Addressing
Column Addressing
Table 2:
Key Timing Parameters
CL = CAS (READ) Latency; minimum clock rate @ CL = 2 (-75E, -75Z), CL = 2.5 (-6, -6T, -75), and CL = 3 (-5B)
Clock Rate
Speed Grade
-5B
-6
6T
-75E/-75Z
-75
CL = 2
133 MHz
133 MHz
133 MHz
133 MHz
100 MHz
CL = 2.5
167 MHz
167 MHz
167 MHz
133 MHz
133 MHz
CL = 3
200 MHz
N/A
N/A
N/A
N/A
Data- Out Window
1.6ns
2.1ns
2.0ns
2.5ns
2.5ns
Access Window
±0.70ns
±0.70ns
±0.70ns
±0.75ns
±0.75ns
DQS–DQ Skew
+0.40ns
+0.40ns
+0.45ns
+0.50ns
+0.50ns
09005aef8076894f
256MBDDRx4x8x16_1.fm - Rev. K 5/05 EN
1
Micron Technology, Inc., reserves the right to change products or specifications without notice.
©2003 Micron Technology, Inc. All rights reserved.
Products and specifications discussed herein are subject to change by Micron without notice.
256Mb: x4, x8, x16 DDR SDRAM
FBGA Part Marking System
Table 3:
Marking
-5B
-6
-6T
-75E
-75Z
-75
-5B
-6/-6T
-75E
-75Z
Speed Grade Compatibility
PC3200 (3-3-3)
Yes
PC2700 (2.5-3-3) PC2100 (2-2-2) PC2100 (2-3-3) PC2100 (2.5-3-3) PC1600 (2-2-2)
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
-75
Yes
Yes
Yes
Yes
Yes
Yes
-75
Figure 1:
256Mb DDR SDRAM Part Numbers
Example Part Number: MT 4 6 V1 6 M1 6 T G- 75 E
-
MT46V
Configuration
Package
Speed
:
Sp.
Op. Temp. Revision
Revision
:C
x4, x8; x16
Configuration
64 Meg x 4
32 Meg x 8
16 Meg x 16
64M4
32M8
16M16
IT
Package
400-mil TSOP
400-mil TSOP (lead-free)
8x14 FBGA
8x14 FBGA (lead-free)
TG
P
FG
BG
-5B
-6
-6T
-75E
-75Z
-75
Special Options
Standard
:F
x16
:G
x4, x8
Operating Temp
Standard
Industrial Temp
L
Low Power
Speed Grade
tCK = 5ns, CL = 3
tCK = 6ns, CL = 2.5
tCK = 6ns, CL = 2.5
tCK = 7.5ns, CL = 2
tCK = 7.5ns, CL = 2
tCK = 7.5ns, CL = 2.5
FBGA Part Marking System
Due to space limitations, FBGA-packaged components have an abbreviated part mark-
ing that is different from the part number. For a quick convertion of an FBGA code, see
the
FBGA Part Marking Decoder on the Micron web site, www.micron.com/decoder.
09005aef8076894f
256MBDDRx4x8x16_1.fm - Rev. K 5/05 EN
2
Micron Technology, Inc., reserves the right to change products or specifications without notice.
©2003 Micron Technology, Inc. All rights reserved.
256Mb: x4, x8, x16 DDR SDRAM
General Description
General Description
The 256Mb DDR SDRAM is a high-speed CMOS, dynamic random-access memory con-
taining 268,435,456 bits. It is internally configured as a quad-bank DRAM.
The 256Mb DDR SDRAM uses a double-data-rate architecture to achieve high-speed
operation. The double data rate architecture is essentially a 2n-prefetch architecture
with an interface designed to transfer two data words per clock cycle at the I/O pins. A
single read or write access for the 256Mb DDR SDRAM effectively consists of a single 2n-
bit wide, one-clock-cycle data transfer at the internal DRAM core and two correspond-
ing
n-bit
wide, one-half-clock-cycle data transfers at the I/O pins.
A bidirectional data strobe (DQS) is transmitted externally, along with data, for use in
data capture at the receiver. DQS is a strobe transmitted by the DDR SDRAM during
READs and by the memory controller during WRITEs. DQS is edge-aligned with data for
READs and center-aligned with data for WRITEs. The x16 offering has two data strobes,
one for the lower byte and one for the upper byte.
The 256Mb DDR SDRAM operates from a differential clock (CK and CK#); the crossing of
CK going HIGH and CK# going LOW will be referred to as the positive edge of CK. Com-
mands (address and control signals) are registered at every positive edge of CK. Input
data is registered on both edges of DQS, and output data is referenced to both edges of
DQS, as well as to both edges of CK.
Read and write accesses to the DDR SDRAM are burst oriented; accesses start at a
selected location and continue for a programmed number of locations in a programmed
sequence. Accesses begin with the registration of an ACTIVE command, which is then
followed by a READ or WRITE command. The address bits registered coincident with the
ACTIVE command are used to select the bank and row to be accessed. The address bits
registered coincident with the READ or WRITE command are used to select the bank and
the starting column location for the burst access.
The DDR SDRAM provides for programmable READ or WRITE burst lengths of 2, 4, or 8
locations. An auto precharge function may be enabled to provide a self-timed row pre-
charge that is initiated at the end of the burst access.
As with standard SDR SDRAMs, the pipelined, multibank architecture of DDR SDRAMs
allows for concurrent operation, thereby effectively providing high bandwidth by hiding
row precharge and activation time.
An auto refresh mode is provided, along with a power-saving power-down mode. All
inputs are compatible with the JEDEC Standard for SSTL_2. All full drive option outputs
are SSTL_2, Class II compatible.
Notes:
1. The functionality and the timing specifications discussed in this data sheet are for the
DLL-enabled mode of operation.
2. Throughout the data sheet, the various figures and text refer to DQs as “DQ.” The DQ
term is to be interpreted as any and all DQ collectively, unless specifically stated oth-
erwise. Additionally, the x16 is divided into two bytes, the lower byte and upper byte.
For the lower byte (DQ0 through DQ7) DM refers to LDM and DQS refers to LDQS. For
the upper byte (DQ8 through DQ15) DM refers to UDM and DQS refers to UDQS.
3. Complete functionality is described throughout the document and any page or dia-
gram may have been simplified to convey a topic and may not be inclusive of all
requirements.
4. Any specific requirement takes precedence over a general statement.
09005aef8076894f
256MBDDRx4x8x16_1.fm - Rev. K 5/05 EN
3
Micron Technology, Inc., reserves the right to change products or specifications without notice.
©2003 Micron Technology, Inc. All rights reserved.
256Mb: x4, x8, x16 DDR SDRAM
Table of Contents
Table of Contents
Features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1
FBGA Part Marking System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2
General Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3
Pin/Ball Assignments and Descriptions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .10
Functional Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .14
Initialization . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .14
Register Definition . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .15
Mode Register . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .15
Burst Length . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .15
Burst Type . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .15
Read Latency . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .17
Operating Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .19
Extended Mode Register . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .19
Output Drive Strength. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .19
DLL Enable/Disable. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .19
Commands . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .21
DESELECT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .22
NO OPERATION (NOP). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .22
LOAD MODE REGISTER . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .22
ACTIVE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .22
READ . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .22
WRITE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .22
PRECHARGE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .22
Auto Precharge . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .23
BURST TERMINATE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .23
AUTO REFRESH . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .23
SELF REFRESH . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .24
Operations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .25
Bank/Row Activation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .25
READs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .27
WRITEs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .36
PRECHARGE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .47
Power-Down (CKE Not Active) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .47
Absolute Maximum Ratings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .53
Notes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .69
Output Drive Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .75
Data Output Timing Diagrams. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .77
Initialization . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .81
Timing Diagrams. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .83
Package Drawings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .92
09005aef8076894f
256MBDDRx4x8x16TOC.fm - Rev. K 5/05 EN
4
Micron Technology, Inc., reserves the right to change products or specifications without notice.
©2003 Micron Technology, Inc. All rights reserved.
256Mb: x4, x8, x16 DDR SDRAM
List of Figures
List of Figures
Figure 1:
Figure 2:
Figure 3:
Figure 4:
Figure 5:
Figure 6:
Figure 7:
Figure 8:
Figure 9:
Figure 10:
Figure 11:
Figure 12:
Figure 13:
Figure 14:
Figure 15:
Figure 16:
Figure 17:
Figure 18:
Figure 19:
Figure 20:
Figure 21:
Figure 22:
Figure 24:
Figure 25:
Figure 26:
Figure 27:
Figure 28:
Figure 29:
Figure 30:
Figure 31:
Figure 32:
Figure 33:
Figure 34:
Figure 35:
Figure 36:
Figure 37:
Figure 38:
Figure 39:
Figure 40:
Figure 41:
Figure 42:
Figure 43:
Figure 44:
Figure 45:
Figure 46:
Figure 47:
Figure 48:
Figure 49:
Figure 50:
Figure 51:
Figure 52:
Figure 53:
Figure 54:
Figure 55:
256Mb DDR SDRAM Part Numbers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2
Functional Block Diagram: 64 Meg x 4. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7
Functional Block Diagram: 32 Meg x 8. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .8
Functional Block Diagram: 16 Meg x 16. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9
Pin Assignment (Top View) 66-Pin TSOP . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .12
60-Ball FBGA Ball Assignment (Top View) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .13
Mode Register Definition . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .16
CAS Latency . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .18
Extended Mode Register Definition . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .20
Activating a Specific Row in a Specific Bank . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .25
Example: Meeting
t
RCD (
t
RRD) MIN When 2 <
t
RCD (
t
RRD) MIN/
t
CK
≤
3 . . . . . . . . . . . . . . . . . . . . . .26
READ Command. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .28
READ Burst. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .29
Consecutive READ Bursts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .30
Nonconsecutive READ Bursts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .31
Random READ Accesses . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .32
Terminating a READ Burst . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .33
READ to WRITE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .34
READ to PRECHARGE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .35
WRITE Command . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .37
WRITE Burst. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .38
Consecutive WRITE to WRITE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .39
Random WRITE Cycles . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .40
WRITE to READ - Uninterrupting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .41
WRITE to READ – Interrupting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .42
WRITE to READ – Odd Number of Data, Interrupting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .43
WRITE to PRECHARGE - Uninterrupting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .44
WRITE to PRECHARGE – Interrupting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .45
WRITE to PRECHARGE – Odd Number of Data – Interrupting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .46
PRECHARGE Command . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .47
Power-Down . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .48
Input Voltage Waveform . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .55
SSTL_2 Clock Input . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .56
Derating Data Valid Window (
t
QH -
t
DQSQ) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .71
Full Drive Pull-Down Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .72
Full Drive Pull-Up Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .72
Reduced Drive Pull-Down Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .73
Reduced Drive Pull-Up Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .73
x4, x8 Data Output Timing –
t
DQSQ,
t
QH, and Data Valid Window . . . . . . . . . . . . . . . . . . . . . . . . . . . .77
x16 Data Output Timing –
t
DQSQ,
t
QH, and Data Valid Window . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .78
Data Output Timing –
t
AC and
t
DQSCK . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .79
Data Input Timing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .80
Initialization Flow Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .82
Initialize and Load Mode Registers. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .83
Power-Down Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .84
Auto Refresh Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .85
Self Refresh Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .86
Bank Read - Without Auto Precharge . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .87
Bank Read - With Auto Precharge . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .88
Bank Write - Without Auto Precharge . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .89
Bank Write - With Auto Precharge . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .90
Write – DM Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .91
66-Pin Plastic TSOP (400 mil). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .92
60-Ball FBGA (8x14mm) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .93
09005aef8076894f
256MBDDRx4x8x16LOF.fm - Rev. K 5/05 EN
5
Micron Technology, Inc., reserves the right to change products or specifications without notice.
©2003 Micron Technology, Inc. All rights reserved.
模拟电子
京公网安备 11010802033920号
Copyright © 2005-2026 EEWORLD.com.cn, Inc. All rights reserved
电子工程世界
