256Mb: x8, x16 Automotive DDR SDRAM

Features

Automotive DDR SDRAM

MT46V32M8 – 8 Meg x 8 x 4 banks
MT46V16M16 – 4 Meg x 16 x 4 banks

Features Options Marking

• VDD = 2.5V ±0.2V, VDDQ = 2.5V ±0.2V • Configuration
VDD = 2.6V ±0.1V, VDDQ = 2.6V ±0.1V (DDR400)1 – 32 Meg x 8 (8 Meg x 8 x 4 banks) 32M8
• Bidirectional data strobe (DQS) transmitted/ – 16 Meg x 16 (4 Meg x 16 x 4 banks) 16M16
received with data, that is, source-synchronous data • Plastic package – OCPL
capture (x16 has two – one per byte) – 66-pin TSOP TG
• Internal, pipelined double-data-rate (DDR) – 66-pin TSOP (Pb-free) P
architecture; two data accesses per clock cycle • Plastic package
• Differential clock inputs (CK and CK#) – 60-ball FBGA (8mm x 12.5mm) CV
• Commands entered on each positive CK edge – 60-ball FBGA (8mm x 12.5mm) CY
• DQS edge-aligned with data for READs; center- (Pb-free)
aligned with data for WRITEs • Timing – cycle time
• DLL to align DQ and DQS transitions with CK – 5ns @ CL = 3 (DDR400) -5B
• Four internal banks for concurrent operation • Self refresh
• Data mask (DM) for masking write data – Standard None
(x16 has two – one per byte) – Low-power self refresh L
• Programmable burst lengths (BL): 2, 4, or 8 • Temperature rating
• Auto refresh – Industrial (–40C to +85C) AIT
– 64ms, 8192-cycle(AIT) – Automotive (–40C to +105C) AAT
– 16ms, 8192-cycle (AAT) • Revision
• Self refresh (not available on AAT devices) – x8, x16 :M
• Longer-lead TSOP for improved reliability (OCPL)
• 2.5V I/O (SSTL_2-compatible) Notes: 1. DDR400 devices operating at < DDR333 con-
• Concurrent auto precharge option supported ditions can use VDD/VDDQ = 2.5V +0.2V.
• tRAS lockout supported (tRAP = tRCD) 2. Not all options listed can be combined to
• AEC-Q100 define an offered product. Use the Part Cata-
• PPAP submission log Search on www.micron.com for product
• 8D response time offerings and availability.

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Products and specifications discussed herein are subject to change by Micron without notice.
 256Mb: x8, x16 Automotive DDR SDRAM
Features

Table 1: Key Timing Parameters

CL = CAS (READ) latency; MIN clock rate with 50% duty cycle at CL = 2 (-75E, -75Z), CL = 2.5 (-6, -6T, -75), and
CL = 3 (-5B)

Clock Rate (MHz)

Access DQS–DQ
Speed Grade CL = 2 CL = 2.5 CL = 3 Data-Out Window Window Skew
-5B 133 167 200 1.6ns ±0.70ns +0.40ns
-6 133 167 n/a 2.1ns ±0.70ns +0.40ns
6T 133 167 n/a 2.0ns ±0.70ns +0.45ns
-75E/-75Z 133 133 n/a 2.5ns ±0.75ns +0.50ns
-75 100 133 n/a 2.5ns ±0.75ns +0.50ns

Table 2: Addressing

Parameter 32 Meg x 8 16 Meg x 16

Configuration 8 Meg x 8 x 4 banks 4 Meg x 16 x 4 banks
Refresh count 8K 8K
Row address 8K (A[12:0]) 8K (A[12:0])
Bank address 4 (BA[1:0]) 4 (BA[1:0])
Column address 1K (A[9:0]) 512 (A[8:0])

Table 3: Speed Grade Compatibility

Marking PC3200 (3-3-3) PC2700 (2.5-3-3) PC2100 (2-2-2) PC2100 (2-3-3) PC2100 (2.5-3-3) PC1600(2-2-2)
-5B1 Yes Yes Yes Yes Yes Yes

-6 – Yes Yes Yes Yes Yes

-6T – Yes Yes Yes Yes Yes

-75E – – Yes Yes Yes Yes

-75Z – – – Yes Yes Yes

-75 – – – – Yes Yes

-5B -6/-6T -75E -75Z -75 -75

Notes: 1. The -5B device is backward compatible with all slower speed grades. The voltage range of
-5B device operating at slower speed grades is VDD = VDDQ = 2.5V ± 0.2V.

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 256Mb: x8, x16 Automotive DDR SDRAM
Features

Figure 1: 256Mb DDR SDRAM Part Numbers

Example Part Number: MT 4 6 V1 6 M1 6 P -5 B AIT:M

- :
Sp.
MT46V Configuration Package Speed Op. Temp. Revision

Revision
Configuration
:M x8, x16
32 Meg x 8 32M8
16 Meg x 16 16M16
Operating Temperature
AIT Automotive Industrial Temp
Package
AAT Automotive Temp
400-mil TSOP TG
400-mil TSOP (Pb-free) P
8mm x 12.5mm FBGA CV
Special Options
8mm x 12.5mm FBGA (Pb-free) CY
Standard
L Low power

Speed Grade
-5B tCK = 5ns, CL = 3

FBGA Part Marking System

Due to space limitations, FBGA-packaged components have an abbreviated part
marking that is different from the part number. For a quick conversion of an FBGA code,
see the FBGA Part Marking Decoder on Micron’s Web site: www.micron.com.

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 256Mb: x8, x16 Automotive DDR SDRAM
Table of Contents

Table of Contents
Features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1
FBGA Part Marking System 3
State Diagram. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5
Functional Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6
General Notes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6
Automotive Industrial Tempature . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7
Automotive Tempature. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7
Functional Block Diagrams. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .8
Pin and Ball Assignments and Descriptions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .10
Package Dimensions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .14
Electrical Specifications – IDD . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .16
Electrical Specifications – DC and AC. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .17
Notes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .34
Commands . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .42
DESELECT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .46
NO OPERATION (NOP). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .46
LOAD MODE REGISTER (LMR) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .46
ACTIVE (ACT) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .47
READ . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .48
WRITE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .49
PRECHARGE (PRE) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .50
BURST TERMINATE (BST) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .50
AUTO REFRESH (AR). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .50
SELF REFRESH . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .50
Operations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .51
INITIALIZATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .51
REGISTER DEFINITION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .54
Mode Register 54
Extended Mode Register 57
ACTIVE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .58
READ . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .59
WRITE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .71
PRECHARGE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .84
Auto Precharge 84
AUTO REFRESH . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .86
SELF REFRESH . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .87
Power-down (CKE Not Active) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .89

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 Important Notes and Warnings

Important Notes and Warnings

Micron Technology, Inc. ("Micron") reserves the right to make changes to information published in this document,
including without limitation specifications and product descriptions. This document supersedes and replaces all
information supplied prior to the publication hereof. You may not rely on any information set forth in this docu-
ment if you obtain the product described herein from any unauthorized distributor or other source not authorized
by Micron.
Automotive Applications. Products are not designed or intended for use in automotive applications unless specifi-
cally designated by Micron as automotive-grade by their respective data sheets. Distributor and customer/distrib-
utor shall assume the sole risk and liability for and shall indemnify and hold Micron harmless against all claims,
costs, damages, and expenses and reasonable attorneys' fees arising out of, directly or indirectly, any claim of
product liability, personal injury, death, or property damage resulting directly or indirectly from any use of non-
automotive-grade products in automotive applications. Customer/distributor shall ensure that the terms and con-
ditions of sale between customer/distributor and any customer of distributor/customer (1) state that Micron
products are not designed or intended for use in automotive applications unless specifically designated by Micron
as automotive-grade by their respective data sheets and (2) require such customer of distributor/customer to in-
demnify and hold Micron harmless against all claims, costs, damages, and expenses and reasonable attorneys'
fees arising out of, directly or indirectly, any claim of product liability, personal injury, death, or property damage
resulting from any use of non-automotive-grade products in automotive applications.
Critical Applications. Products are not authorized for use in applications in which failure of the Micron compo-
nent could result, directly or indirectly in death, personal injury, or severe property or environmental damage
("Critical Applications"). Customer must protect against death, personal injury, and severe property and environ-
mental damage by incorporating safety design measures into customer's applications to ensure that failure of the
Micron component will not result in such harms. Should customer or distributor purchase, use, or sell any Micron
component for any critical application, customer and distributor shall indemnify and hold harmless Micron and
its subsidiaries, subcontractors, and affiliates and the directors, officers, and employees of each against all claims,
costs, damages, and expenses and reasonable attorneys' fees arising out of, directly or indirectly, any claim of
product liability, personal injury, or death arising in any way out of such critical application, whether or not Mi-
cron or its subsidiaries, subcontractors, or affiliates were negligent in the design, manufacture, or warning of the
Micron product.
Customer Responsibility. Customers are responsible for the design, manufacture, and operation of their systems,
applications, and products using Micron products. ALL SEMICONDUCTOR PRODUCTS HAVE INHERENT FAIL-
URE RATES AND LIMITED USEFUL LIVES. IT IS THE CUSTOMER'S SOLE RESPONSIBILITY TO DETERMINE
WHETHER THE MICRON PRODUCT IS SUITABLE AND FIT FOR THE CUSTOMER'S SYSTEM, APPLICATION, OR
PRODUCT. Customers must ensure that adequate design, manufacturing, and operating safeguards are included
in customer's applications and products to eliminate the risk that personal injury, death, or severe property or en-
vironmental damages will result from failure of any semiconductor component.
Limited Warranty. In no event shall Micron be liable for any indirect, incidental, punitive, special or consequential
damages (including without limitation lost profits, lost savings, business interruption, costs related to the removal
or replacement of any products or rework charges) whether or not such damages are based on tort, warranty,
breach of contract or other legal theory, unless explicitly stated in a written agreement executed by Micron's duly
authorized representative.

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 256Mb: x8, x16 Automotive DDR SDRAM
State Diagram

State Diagram
Figure 2: Simplified State Diagram

Power Power
applied on

PRE

Precharge
all banks
Self
refresh
LMR REFS

Idle REFSX
LMR
MR all banks REFA Auto
EMR precharged refresh
CKEL

CKEH

Active ACT Precharge

power- CKE HIGH power-
down down

CKE LOW
Row Burst
active stop

WRITE READ

WRITE BST READ

WRITE A READ A
Write READ Read

WRITE A READ A
READ A
PRE
PRE PRE
Write A Read A

PRE Precharge
PREALL
Automatic sequence
Command sequence

ACT = ACTIVE PRE = PRECHARGE

BST = BURST TERMINATE PREALL = PRECHARGE all banks
CKEH = Exit power-down READ A = READ with auto precharge
CKEL = Enter power-down REFA = AUTO REFRESH
EMR = Extended mode register REFS = Enter self refresh
LMR = LOAD MODE REGISTER REFSX = Exit self refresh
MR = Mode register WRITE A = WRITE with auto precharge

Note: This diagram represents operations within a single bank only and does not capture concur-
rent operations in other banks.

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 256Mb: x8, x16 Automotive DDR SDRAM
Functional Description

Functional Description
The 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 inter-
face designed to transfer two data words per clock cycle at the I/O pins. A single read or
write access for the DDR SDRAM effectively consists of a single 2n-bit-wide, one-clock-
cycle data transfer at the internal DRAM core and two corresponding 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 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.
Commands (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 may then
be 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
precharge 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 providing high effective 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.

General Notes
• The functionality and the timing specifications discussed in this data sheet are for the
DLL-enabled mode of operation.
• 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
otherwise. Additionally, the x16 is divided into two bytes, the lower byte and upper
byte. For the lower byte (DQ[7:0] DM refers to LDM and DQS refers to LDQS. For the
upper byte (DQ[15:8] DM refers to UDM and DQS refers to UDQS.
• Complete functionality is described throughout the document and any page or
diagram may have been simplified to convey a topic and may not be inclusive of all
requirements.
• Any specific requirement takes precedence over a general statement.

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 256Mb: x8, x16 Automotive DDR SDRAM
Functional Description

Automotive Industrial Tempature

The automotive temperature (AIT) option, Ambient and case temperatures cannot be
less than –40C or greater than 85C

Automotive Tempature
The automotive temperature (AAT) option adheres to the following specifications:
• 16ms refresh rate
• Self refresh not supported
• Ambient and case temperatures cannot be less than –40C or greater than 105C

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 256Mb: x8, x16 Automotive DDR SDRAM
Functional Block Diagrams

Functional Block Diagrams

The 256Mb DDR SDRAM is a high-speed CMOS, dynamic random-access memory
containing 268,435,456 bits. It is internally configured as a 4-bank DRAM.

Figure 3: 32 Meg x 8 Functional Block Diagram

CKE
CK#
CK

CS# CONTROL
COMMAND

LOGIC
DECODE

WE#
BANK3
CAS# BANK2
RAS# BANK1

REFRESH 13
MODE REGISTERS COUNTER
ROW- 13 BANK0
ADDRESS ROW- CK
BANK0
MUX ADDRESS MEMORY
15 8192
LATCH ARRAY
13 & (8192 x 512 x 16) DATA DLL
DECODER 8

16 8
READ MUX
SENSE AMPLIFIERS LATCH 8 DRVRS

DQS 1
8192
GENERATOR
DQ[7:0]
COL0 DQS
2 I/O GATING INPUT
DM MASK LOGIC 16 REGISTERS
DQS
BANK
A[12:0], 1 1
ADDRESS CONTROL
BA[1:0] 15 MASK
1
REGISTER LOGIC
2 WRITE 1 1
512 16 FIFO 2
(x16) & RCVRS
8 8 DM
DRIVERS
16 8
8 8
COLUMN CK CK
Out In DATA
DECODER
COLUMN-
ADDRESS 9 CK
10 COUNTER/ 1
LATCH COL0

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 256Mb: x8, x16 Automotive DDR SDRAM
Functional Block Diagrams

Figure 4: 16 Meg x 16 Functional Block Diagram

CKE
CK#
CK

CS# CONTROL
COMMAND

LOGIC
DECODE

WE#
BANK3
CAS# BANK2
RAS# REFRESH BANK1
COUNTER
13

MODE REGISTERS
ROW- 13 BANK0
ADDRESS ROW- CK
BANK0
MUX ADDRESS MEMORY
15 8192
LATCH ARRAY
13 & (8,192 x 256 x 32) DATA DLL
DECODER 16

32 16
READ MUX
SENSE AMPLIFIERS LATCH 16 DRVRS

DQS 2
8192
GENERATOR
DQ[15:0]
COL0
DQS
2 I/O GATING INPUT
DM MASK LOGIC 32 REGISTERS LDQS
BANK UDQS
A[12:0], 2 2
ADDRESS CONTROL
BA[1:0] 15 MASK
2
REGISTER LOGIC
2 WRITE 2 2
256 32 FIFO 4
(x32) & RCVRS
16 16 LDM,
DRIVERS UDM
32 16
16 16
COLUMN CK CK
Out In DATA
DECODER
COLUMN-
ADDRESS 8 CK
9 COUNTER/ 2
LATCH
COL0

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 256Mb: x8, x16 Automotive DDR SDRAM
Pin and Ball Assignments and Descriptions

Pin and Ball Assignments and Descriptions

Figure 5: 66-Pin TSOP Pin Assignments (Top View)

x8 x16 x16 x8
VDD VDD 1 66 VSS VSS
DQ0 DQ0 2 65 DQ15 DQ7
VDDQ VDDQ 3 64 VSSQ VSSQ
NC DQ1 4 63 DQ14 NC
DQ1 DQ2 5 62 DQ13 DQ6
VSSQ VSSQ 6 61 VDDQ VDDQ
NC DQ3 7 60 DQ12 NC
DQ2 DQ4 8 59 DQ11 DQ5
VDDQ VDDQ 9 58 VSSQ VSSQ
NC DQ5 10 57 DQ10 NC
DQ3 DQ6 11 56 DQ9 DQ4
VSSQ VSSQ 12 55 VDDQ VDDQ
NC DQ7 13 54 DQ8 NC
NC NC 14 53 NC NC
VDDQ VDDQ 15 52 VSSQ VSSQ
NC LDQS 16 51 UDQS DQS
NC NC 17 50 DNU DNU
VDD VDD 18 49 VREF VREF
DNU DNU 19 48 VSS VSS
NC LDM 20 47 UDM DM
WE# WE# 21 46 CK# CK#
CAS# CAS# 22 45 CK CK
RAS# RAS# 23 44 CKE CKE
CS# CS# 24 43 NC NC
NC NC 25 42 A12 A12
BA0 BA0 26 41 A11 A11
BA1 BA1 27 40 A9 A9
A10/AP A10/AP 28 39 A8 A8
A0 A0 29 38 A7 A7
A1 A1 30 37 A6 A6
A2 A2 31 36 A5 A5
A3 A3 32 35 A4 A4
VDD VDD 33 34 VSS VSS

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 256Mb: x8, x16 Automotive DDR SDRAM
Pin and Ball Assignments and Descriptions

Figure 6: 60-Ball FBGA Ball Assignments (Top View)

x8 (Top View)
1 2 3 4 5 6 7 8 9

VSSQ DQ7 VSS A VDD DQ0 VDDQ

NC VDDQ DQ6 B DQ1 VSSQ NC
NC VSSQ DQ5 C DQ2 VDDQ NC
NC VDDQ DQ4 D DQ3 VSSQ NC
NC VSSQ DQS E NC VDDQ NC
VREF VSS DM F NC VDD DNU
CK CK# G WE# CAS#
A12 CKE H RAS# CS#
A11 A9 J BA1 BA0
A8 A7 K A0 A10
A6 A5 L A2 A1
A4 VSS M VDD A3

x16 (Top View)

1 2 3 4 5 6 7 8 9

VSSQ DQ15 VSS A VDD DQ0 VDDQ

DQ14 VDDQ DQ13 B DQ2 VSSQ DQ1
DQ12 VSSQ DQ11 C DQ4 VDDQ DQ3
DQ10 VDDQ DQ9 D DQ6 VSSQ DQ5
DQ8 VSSQ UDQS E LDQS VDDQ DQ7
VREF VSS UDM F LDM VDD DNU
CK CK# G WE# CAS#
A12 CKE H RAS# CS#
A11 A9 J BA1 BA0
A8 A7 K A0 A10
A6 A5 L A2 A1
A4 VSS M VDD A3

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 256Mb: x8, x16 Automotive DDR SDRAM
Pin and Ball Assignments and Descriptions

Table 4: Pin and Ball Descriptions

FBGA TSOP
Numbers Numbers Symbol Type Description
K7, L8, L7, 29, 30, 31, A0, A1, A2, Input Address inputs: Provide the row address for ACTIVE commands,
M8, M2, L3, 32, 35, 36, A3, A4, A5, and the column address and auto precharge bit (A10) for READ/
L2, K3, K2, 37, 38, 39, A6, A7, A8, WRITE commands, to select one location out of the memory array
J3, K8, 40, 28 A9, A10, in the respective bank. A10 sampled during a PRECHARGE
J2, H2 41, 42 A11, A12 command determines whether the PRECHARGE applies to one
bank (A10 LOW, bank selected by BA[1:0]) or all banks (A10 HIGH).
The address inputs also provide the op-code during a LOAD MODE
REGISTER command.
J8, J7 26, 27 BA0, BA1 Input Bank address inputs: BA[1:0] define to which bank an ACTIVE,
READ, WRITE, or PRECHARGE command is being applied. BA[1:0]
also define which mode register (mode register or extended mode
register) is loaded during the LOAD MODE REGISTER (LMR)
command.
G2, G3 45, 46 CK, CK# Input Clock: CK and CK# are differential clock inputs. All address and
control input signals are sampled on the crossing of the positive
edge of CK and the negative edge of CK#. Output data (DQ and
DQS) is referenced to the crossings of CK and CK#.
H3 44 CKE Input Clock enable: CKE HIGH activates and CKE LOW deactivates the
internal clock, input buffers, and output drivers. Taking CKE LOW
provides PRECHARGE POWER-DOWN and SELF REFRESH operations
(all banks idle) or ACTIVE POWER-DOWN (row ACTIVE in any bank).
CKE is synchronous for POWER-DOWN entry and exit and for SELF
REFRESH entry. CKE is asynchronous for SELF REFRESH exit and for
disabling the outputs. CKE must be maintained HIGH throughout
read and write accesses. Input buffers (excluding CK, CK#, and CKE)
are disabled during POWER- DOWN. Input buffers (excluding CKE)
are disabled during SELF REFRESH. CKE is an SSTL_2 input but will
detect an LVCMOS LOW level after VDD is applied and until CKE is
first brought HIGH, after which it becomes a SSTL_2 input only.
H8 24 CS# Input Chip select: CS# enables (registered LOW) and disables (registered
HIGH) the command decoder. All commands are masked when CS#
is registered HIGH. CS# provides for external bank selection on
systems with multiple banks. CS# is considered part of the
command code.
F3 47 DM Input Input data mask: DM is an input mask signal for write data. Input
F7, F3 20, 47 LDM, UDM data is masked when DM is sampled HIGH along with that input
data during a WRITE access. DM is sampled on both edges of DQS.
Although DM pins are input-only, the DM loading is designed to
match that of DQ and DQS pins. For the x16, LDM is DM for DQ[7:0]
and UDM is DM for DQ[15:8]. Pin 20 is a NC on x8.
H7, G8, G7 23, 22, 21 RAS#, CAS#, Input Command inputs: RAS#, CAS#, and WE# (along with CS#) define
WE# the command being entered.
A8, B9, B7, 2, 4, 5, DQ[2:0] I/O Data input/output: Data bus for x16.
C9, C7, D9, 7, 8, 10, DQ[5:3]
D7, E9, E1, 11, 13, 54, DQ[8:6]
D3, D1, C3, 56, 57, 59, DQ[11:9]
C1, B3, B1, 60, 62, 63, DQ[14:12]
A2 65 DQ15
A8, B7, C7, 2, 5, 8, DQ[2:0] I/O Data input/output: Data bus for x8.
D7, D3, C3, 11, 56, 59, DQ[5:3]
B3, A2 62, 65 DQ[7:6]

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 256Mb: x8, x16 Automotive DDR SDRAM
Pin and Ball Assignments and Descriptions

Table 4: Pin and Ball Descriptions (continued)

FBGA TSOP
Numbers Numbers Symbol Type Description
E3 51 DQS I/O Data strobe: Output with read data, input with write data. DQS is
E7 16 LDQS edge-aligned with read data, centered in write data. It is used to
E3 51 UDQS capture data. For the x16, LDQS is DQS for DQ[7:0] and UDQS is
DQS for DQ[15:8]. Pin 16 (E7) is NC on x8.
F8, M7, A7 1, 18, 33 VDD Supply Power supply.
B2, D2, C8, 3, 9, 15, VDDQ Supply DQ power supply: Isolated on the die for improved noise
E8, A9 55, 61 immunity.
A3, F2, M3 34, 48, 66 VSS Supply Ground.
A1, C2, E2, 6, 12, 52, VSSQ Supply DQ ground: Isolated on the die for improved noise immunity.
B8, D8 58, 64
F1 49 VREF Supply SSTL_2 reference voltage.
– 14, 17, 25, NC – No connect for x16: These pins should be left unconnected.
43, 53
B1, B9, C1, 4, 7, 10, 13, NC – No connect for x8: These pins should be left unconnected.
C9, D1, D9, 14, 16, 17,
E1, E7, E9, F7 20, 25, 43,
53, 54, 57,
60, 63
F9 19, 50 DNU – Do not use: Must float to minimize noise on VREF.

Table 5: Reserved NC Pin Descriptions

NC pins not listed may also be reserved for other uses; this table defines NC pins of importance

TSOP Numbers Symbol Type Description

17 A13 Input Address input A13 for 1Gb devices.

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 256Mb: x8, x16 Automotive DDR SDRAM
Package Dimensions

Package Dimensions
Figure 7: 66-Pin Plastic TSOP (400 mil)

SEE DETAIL A
22.22 ± 0.08
0.71
0.65 TYP
0.10 (2X)

0.32 ±0.075 TYP

11.76 ± 0.20

10.16 ±0.08

PIN #1 ID +0.03
0.15 –0.02
GAGE PLANE
0.25

+0.10
0.10
–0.05
0.10
0.80 TYP
1.20 MAX
0.50 ±0.10

DETAIL A

Notes: 1. All dimensions in millimeters.

2. Package width and length do not include mold protrusion; allowable mold protrusion is
0.25mm per side.

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 256Mb: x8, x16 Automotive DDR SDRAM
Package Dimensions

Figure 8: 60-Ball FBGA (8mm x 12.5mm)

0.8 ±0.1
Seating
plane
A
0.12 A

60X Ø0.45
Solder ball material:
eutectic or SAC305.
Dimensions apply
to solder balls post-
Ball A1 ID Ball A1 ID
reflow on Ø0.33 9 8 7 3 2 1
NSMD ball pads.
A
B
C
D
E
F
11 CTR 12.5 ±0.15
G
H
J
1 TYP
K
L
M

0.8 TYP
6.4 CTR 1.20 MAX

8 ±0.15 0.25 MIN

Notes: 1. All dimensions are in millimeters.

2. Topside part marking decoder can be found on Micron’s Web site.

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 256Mb: x8, x16 Automotive DDR SDRAM
Electrical Specifications – IDD

Electrical Specifications – IDD

Table 6: IDD Specifications and Conditions (x8, x16: -5B)
VDDQ = 2.6V ±0.1V, VDD = 2.6V ±0.1V (-5B); 0°C TA  +70°C; Notes: 1–5, 11, 13, 15, 47; Notes appear on
pages 34–39; See also Table 7 on page 17

Parameter/Condition Symbol -5B -6/6T Units Notes

Operating one-bank precharge current: RC = RC (MIN); t t IDD0 75 65 mA 23, 48
tCK = tCK (MIN); DQ, DM, and DQS inputs changing once per clock cycle;
Address and control inputs changing once every two clock cycles
Operating one-bank active-read-precharge current: Burst = 4; IDD1 85 75 mA 23, 48
t
RC = tRC (MIN); tCK = tCK (MIN); IOUT = 0mA; Address and control inputs
changing once per clock cycle
Precharge power-down standby current: All banks idle; Power-down IDD2P 4 4 mA 24, 33
mode; tCK = tCK (MIN); CKE = LOW
Idle standby current: CS# = HIGH; All banks are idle; tCK = tCK (MIN); IDD2F 23 23 mA 51
CKE = HIGH; Address and other control inputs changing once per clock
cycle; VIN = VREF for DQ, DQS, and DM
Active power-down standby current: One bank active; Power-down IDD3P 14 14 mA 24, 33
mode; tCK = tCK (MIN); CKE = LOW
Active standby current: CS# = HIGH; CKE = HIGH; One bank active; IDD3N 30 30 mA 23
tRC = tRAS (MAX); tCK = tCK (MIN); DQ, DM, and DQS inputs changing

twice per clock cycle; Address and other control inputs changing once per
clock cycle
Operating burst read current: Burst = 2; Continuous burst reads; IDD4R 105 95 mA 23, 48
One bank active; Address and control inputs changing once per clock
cycle; tCK = tCK (MIN); IOUT = 0mA
Operating burst write current: Burst = 2; Continuous burst writes; One IDD4W 105 95 mA 23
bank active; Address and control inputs changing once per clock cycle;
tCK = tCK (MIN); DQ, DM, and DQS inputs changing twice per clock cycle

Auto refresh burst current: tREFC = tRFC (MIN) IDD5 115 105 mA 50
tREFC =7.8µs (AIT) IDD5A 6 6 mA 28, 50
tREFC =1.95µs (AAT) IDD5A 9 9 mA 28, 50
Self refresh current: CKE  0.2V Standard IDD6 4 4 mA 12
(Not supported for AAT) Low power (L) IDD6A 2 2 mA 12
Operating bank interleave read current: Four-bank interleaving IDD7 175 175 mA 23, 49
READs (burst = 4) with auto precharge; tRC = minimum tRC allowed;
tCK = tCK (MIN); Address and control inputs change only during ACTIVE,

READ, or WRITE commands

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 256Mb: x8, x16 Automotive DDR SDRAM
Electrical Specifications – DC and AC

Electrical Specifications – DC and AC

Stresses greater than those listed in Table 7 may cause permanent damage to the device.
This is a stress rating only, and functional operation of the device at these or any other
conditions above those indicated in the operational sections of this specification is not
implied. Exposure to absolute maximum rating conditions for extended periods may
affect reliability.

Table 7: Absolute Maximum Ratings

Parameter Min Max Units

VDD supply voltage relative to VSS –1V 3.6V V
VDDQ supply voltage relative to VSS –1V 3.6V V
VREF and inputs voltage relative to VSS –1V 3.6V V
I/O pins voltage relative to VSS –0.5V VDDQ + 0.5V V
Storage temperature (plastic) –55 150 °C
Short circuit output current – 50 mA

Table 8: DC Electrical Characteristics and Operating Conditions (-5B)

Notes: 1–5 and 17 apply to the entire table; Notes appear on page 34; VDDQ = 2.6V ±0.1V, VDD = 2.6V ±0.1V

Parameter/Condition Symbol Min Max Units Notes

Supply voltage VDD 2.5 2.7 V 37, 42
I/O supply voltage VDDQ 2.5 2.7 V 37, 42, 45
I/O reference voltage VREF 0.49 × VDDQ 0.51 × VDDQ V 7, 45
I/O termination voltage (system) VTT VREF - 0.04 VREF + 0.04 V 8, 45
Input high (logic 1) voltage VIH(DC) VREF + 0.15 VDD + 0.3 V 29
Input low (logic 0) voltage VIL(DC) –0.3 VREF - 0.15 V 29
Input leakage current: II –2 2 µA
Any input 0V  VIN  VDD, VREF pin 0V  VIN  1.35V
(All other pins not under test = 0V)
Output leakage current: IOZ –5 5 µA
(DQ are disabled; 0V VOUT  VDDQ)
Full-drive option output High current (VOUT = IOH –16.8 – mA 38, 40
levels (x8, x16): VDDQ - 0.373V, minimum
VREF, minimum VTT)
Low current (VOUT = IOL 16.8 – mA
0.373V, maximum VREF,
maximum VTT)
Reduced-drive option High current (VOUT = IOHR –9 – mA 39, 40
output levels VDDQ - 0.373V, minimum
VREF, minimum VTT)
Low current (VOUT = IOLR 9 – mA
0.373V, maximum VREF,
maximum VTT)
Ambient operating Commercial TA 0 70 °C
temperatures Industrial (AIT) TA –40 85 °C
Automotive (AAT) TA –40 105 °C

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 256Mb: x8, x16 Automotive DDR SDRAM
Electrical Specifications – DC and AC

Table 9: DC Electrical Characteristics and Operating Conditions (-6, -6T, -75E, -75Z, -75)
Notes: 1–5, 17 apply to the entire table; Notes appear on page 34; VDDQ = 2.5V ±0.2V, VDD = 2.5V ±0.2V

Parameter/Condition Symbol Min Max Units Notes

Supply voltage VDD 2.3 2.7 V 37, 42
I/O supply voltage VDDQ 2.3 2.7 V 37, 42, 45
I/O reference voltage VREF 0.49 × VDDQ 0.51 × VDDQ V 7, 45
I/O termination voltage (system) VTT VREF - 0.04 VREF + 0.04 V 8, 45
Input high (logic 1) voltage VIH(DC) VREF + 0.15 VDD + 0.3 V 29
Input low (logic 0) voltage VIL(DC) –0.3 VREF - 0.15 V 29
Input leakage current: II –2 2 µA
Any input 0V  VIN  VDD, VREF pin 0V  VIN  1.35V
(All other pins not under test = 0V)
Output leakage current: IOZ –5 5 µA
(DQ are disabled; 0V VOUT  VDDQ)
Full-drive option output High current (VOUT = IOH –16.8 – mA 38, 40
levels ( x8, x16): VDDQ - 0.373V, minimum
VREF, minimum VTT)
Low current (VOUT = IOL 16.8 – mA
0.373V, maximum VREF,
maximum VTT)
Reduced-drive option High current (VOUT = IOHR –9 – mA 39, 40
output levels (Design VDDQ - 0.373V, minimum
Revision F and K only): VREF, minimum VTT)
Low current (VOUT = IOLR 9 – mA
0.373V, maximum VREF,
maximum VTT)
Ambient operating Commercial TA 0 70 °C
temperatures Industrial (AIT) TA –40 85 °C
Automotive (AAT) TA –40 105 °C

Table 10: AC Input Operating Conditions

Notes: 1–5, 17 apply to the entire table; Notes appear on page 34;
0°C TA  70°C; VDDQ = 2.5V ±0.2V, VDD = 2.5V ±0.2V (VDDQ = 2.6V ±0.1V, VDD = 2.6V ±0.1V for -5B)

Parameter/Condition Symbol Min Max Units Notes

Input high (logic 1) voltage VIH(AC) VREF + 0.310 – V 15, 29, 41
Input low (logic 0) voltage VIL(AC) – VREF - 0.310 V 15, 29, 41
I/O reference voltage VREF(AC) 0.49 × VDDQ 0.51 × VDDQ V 7

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 256Mb: x8, x16 Automotive DDR SDRAM
Electrical Specifications – DC and AC

Figure 9: Input Voltage Waveform

VDDQ (2.3V MIN)

VOH,min (1.670V1 for SSTL_2 termination)

System noise margin (power/ground,

crosstalk, signal integrity attenuation)
1.560V VIH(AC)

1.400V VIH(DC)

1.300V
VREF + AC noise
1.275V
VREF + DC error
1.250V
VREF - DC error
1.225V
VREF - AC noise
1.200V

1.100V VIL(DC)

0.940V VIL(DC)
VIN(AC) - provides margin
between VOL,max and VIL(AC)
Receiver

VOL,max (0.83V2 for SSTL_2

termination)

VSSQ
Transmitter

Notes: 1. VOH,min with test load is 1.927V.

2. VOL,max with test load is 0.373V.
3. Numbers in diagram reflect nominal values utilizing circuit below for all devices other than
-5B.

VTT
25Ω

25Ω Reference
point

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 256Mb: x8, x16 Automotive DDR SDRAM
Electrical Specifications – DC and AC

Table 11: Clock Input Operating Conditions

Notes: 1–5, 16, 17, 31 apply to the entire table; Notes appear on page 34;
0°C TA  70°C; VDDQ = 2.5V ±0.2V, VDD = 2.5V ±0.2V (VDDQ = 2.6V ±0.1V, VDD = 2.6V ±0.1V for -5B)

Parameter/Condition Symbol Min Max Units Notes

Clock input mid-point voltage: CK and CK# VMP(DC) 1.15 1.35 V 7, 10
Clock input voltage level: CK and CK# VIN(DC) –0.3 VDDQ + 0.3 V 7
Clock input differential voltage: CK and CK# VID(DC) 0.36 VDDQ + 0.6 V 7, 9
Clock input differential voltage: CK and CK# VID(AC) 0.7 VDDQ + 0.6 V 9
Clock input crossing point voltage: CK and CK# VIX(AC) 0.5 × VDDQ - 0.2 0.5 × VDDQ + 0.2 V 10

Figure 10: SSTL_2 Clock Input

2.80V Maximum clock level1

CK#

1.45V X
1.25V VMP(DC)2 VIX(AC)3 VID(DC)4
VID(AC)5
1.05V X

CK

–0.30V Minimum clock level1

Notes: 1. CK or CK# may not be more positive than VDDQ + 0.3V or more negative than VSS - 0.3V.
2. This provides a minimum of 1.15V to a maximum of 1.35V and is always half of VDDQ.
3. CK and CK# must cross in this region.
4. CK and CK# must meet at least VID(DC)min when static and is centered around VMP(DC).
5. CK and CK# must have a minimum 700mV peak-to-peak swing.
6. For AC operation, all DC clock requirements must also be satisfied.
7. Numbers in diagram reflect nominal values for all devices other than -5B.

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 256Mb: x8, x16 Automotive DDR SDRAM
Electrical Specifications – DC and AC

Table 12: Capacitance (x8 TSOP)

Note: 14 applies to the entire table; Notes appear on page 34

Parameter Symbol Min Max Units Notes

Delta input/output capacitance: DQ[7:0] (x8) DCIO – 0.50 pF 25
Delta input capacitance: Command and address DCI1 – 0.50 pF 30
Delta input capacitance: CK, CK# DCI2 – 0.25 pF 30
Input/output capacitance: DQ, DQS, DM CIO 4.0 5.0 pF
Input capacitance: Command and address CI1 2.0 3.0 pF
Input capacitance: CK, CK# CI2 2.0 3.0 pF
Input capacitance: CKE CI3 2.0 3.0 pF

Table 13: Capacitance (x8 FBGA)

Note: 14 applies to the entire table; Notes appear on page 34

Parameter Symbol Min Max Units Notes

Delta input/output capacitance: DQ, DQS, DM DCIO – 0.50 pF 25
Delta input capacitance: Command and address DCI1 – 0.50 pF 30
Delta input capacitance: CK, CK# DCI2 – 0.25 pF 30
Input/output capacitance: DQ, DQS, DM CIO 3.5 4.5 pF
Input capacitance: Command and address CI1 1.5 2.5 pF
Input capacitance: CK, CK# CI2 1.5 2.5 pF
Input capacitance: CKE CI3 1.5 2.5 pF

Table 14: Capacitance (x16 TSOP)

Note: 14 applies to the entire table; Notes appear on page 34

Parameter Symbol Min Max Units Notes

Delta input/output capacitance: DQ[7:0], LDQS, LDM DCIOL – 0.50 pF 25
Delta input/output capacitance: DQ[15:8], UDQS, UDM DCIOU – 0.50 pF 25
Delta input capacitance: Command and address DCI1 – 0.50 pF 30
Delta input capacitance: CK, CK# DCI2 – 0.25 pF 30
Input/output capacitance: DQ, LDQS, UDQS, LDM, UDM CIO 4.0 5.0 pF
Input capacitance: Command and address CI1 2.0 3.0 pF
Input capacitance: CK, CK# CI2 2.0 3.0 pF
Input capacitance: CKE CI3 2.0 3.0 pF

Table 15: Capacitance (x16 FBGA)

Note: 14 applies to the entire table; Notes appear on page 34

Parameter Symbol Min Max Units Notes

Delta input/output capacitance: DQ[7:0], LDQS, LDM DCIOL – 0.50 pF 25
Delta input/output capacitance: DQ[15:8], UDQS, UDM DCIOU – 0.50 pF 25
Delta input capacitance: Command and address DCI1 – 0.50 pF 30
Delta input capacitance: CK, CK# DCI2 – 0.25 pF 30
Input/output capacitance: DQ, LDQS, UDQS, LDM, UDM CIO 3.5 4.5 pF
Input capacitance: Command and address CI1 1.5 2.5 pF
Input capacitance: CK, CK# CI2 1.5 2.5 pF
Input capacitance: CKE CI3 1.5 2.5 pF

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 256Mb: x8, x16 Automotive DDR SDRAM
Electrical Specifications – DC and AC

Table 16: Electrical Characteristics and Recommended AC Operating Conditions (-5B)

Notes 1–6, 16–18, 34 apply to the entire table; Notes appear on page 34;
0°C TA  70°C; VDDQ = 2.6V ±0.1V, VDD = 2.6V ±0.1V

AC Characteristics -5B
Parameter Symbol Min Max Units Notes
t
Access window of DQ from CK/CK# AC –0.70 0.70 ns
t t
CK high-level width CH 0.45 0.55 CK 31
t
Clock cycle time CL = 3 CK (3) 5 7.5 ns 52
tCK (2.5) 6 13 ns 46, 52
CL = 2.5
t
CL = 2 CK (2) 7.5 13 ns 46, 52
t t
CK low-level width CL 0.45 0.55 CK 31
tDH
DQ and DM input hold time relative to DQS 0.40 – ns 27, 32
tDIPW
DQ and DM input pulse width (for each input) 1.75 – ns 32
t
Access window of DQS from CK/CK# DQSCK –0.60 0.60 ns
tDQSH tCK
DQS input high pulse width 0.35 –
tDQSL 0.35 – tCK
DQS input low pulse width
tDQSQ – 0.40 ns 26, 27
DQS–DQ skew, DQS to last DQ valid, per group, per access
tDQSS 0.72 1.28 tCK
WRITE command to first DQS latching transition
t
DQ and DM input setup time relative to DQS DS 0.40 – ns 27, 32
tDSH tCK
DQS falling edge from CK rising – hold time 0.2 –
tDSS 0.2 – tCK
DQS falling edge to CK rising – setup time
t t
Half-clock period HP CH,tCL – ns 35
tHZ – 0.70 ns 19, 43
Data-out High-Z window from CK/CK#
tIH
Address and control input hold time (slew rate 0.5 V/ns) F 0.60 – ns 15
tIPW
Address and control input pulse width (for each input) 2.2 – ns
tIS
Address and control input setup time (slew rate 0.5 V/ns) F 0.60 – ns 15
tLZ –0.70 – ns 19, 43
Data-out Low-Z window from CK/CK#
tMRD
LOAD MODE REGISTER command cycle time 10 – ns
tQH tHP -tQHS
DQ–DQS hold, DQS to first DQ to go non-valid, per access – ns 26, 27
tQHS
Data hold skew factor – 0.50 ns
tRAP 15 – ns
ACTIVE-to-READ with auto precharge command
tRAS
ACTIVE-to-PRECHARGE command 40 70,000 ns 36
t
ACTIVE-to-ACTIVE/AUTO REFRESH command period RC 55 – ns 55
tRCD
ACTIVE-to-READ or WRITE delay 15 – ns
tREFC – 70.3 µs 24
REFRESH-to-REFRESH command interval (Industrial) AIT
tREFC
REFRESH-to-REFRESH command interval (Automotive) AAT – 17.55 µs 24
tREFI – 7.8 µs 24
Average periodic refresh interval (Industrial) AIT
t
Average periodic refresh interval (Automotive) REFIAAT – 1.95 µs 24
tRFC
AUTO REFRESH command period 70 – ns 50
tRP 15 – ns
PRECHARGE command period
tRPRE tCK
DQS read preamble 0.9 1.1 44
tRPST 0.4 0.6 tCK 44
DQS read postamble
t
ACTIVE bank a to ACTIVE bank b command RRD 10 – ns
t
Terminating voltage delay to VDD VTD 0 – ns
tWPRE tCK
DQS write preamble 0.25 –
tWPRES 0 – ns 21, 22
DQS write preamble setup time
tWPST tCK
DQS write postamble 0.4 0.6 20

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DDR_x4x8x16_Core2.fm - Core DDR Rev. B 11/11 EN 22 ©2011 Micron Technology, Inc. All rights reserved.
 256Mb: x8, x16 Automotive DDR SDRAM
Electrical Specifications – DC and AC

Table 16: Electrical Characteristics and Recommended AC Operating Conditions (-5B) (continued)
Notes 1–6, 16–18, 34 apply to the entire table; Notes appear on page 34;
0°C TA  70°C; VDDQ = 2.6V ±0.1V, VDD = 2.6V ±0.1V

AC Characteristics -5B
Parameter Symbol Min Max Units Notes
t
Write recovery time WR 15 – ns
t t
Internal WRITE-to-READ command delay WTR 2 – CK
t
Exit SELF REFRESH-to-non-READ command XSNR 70 – ns
tXSRD 200 – tCK
Exit SELF REFRESH-to-READ command
t
Data valid output window n/a QH - tDQSQ ns 26

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DDR_x4x8x16_Core2.fm - Core DDR Rev. B 11/11 EN 23 ©2011 Micron Technology, Inc. All rights reserved.
 256Mb: x8, x16 Automotive DDR SDRAM
Electrical Specifications – DC and AC

Table 17: Electrical Characteristics and Recommended AC Operating Conditions (-6)

Notes: 1–6, 16–18, 34 apply to the entire table; Notes appear on page 34;
0°C TA  70°C; VDDQ = 2.5V ±0.2V, VDD = 2.5V ±0.2V

AC Characteristics -6 (FBGA)
Parameter Symbol Min Max Units Notes
t
Access window of DQ from CK/CK# AC –0.70 0.70 ns
t t
CK high-level width CH 0.45 0.55 CK 31
t
Clock cycle time CL = 2.5 CK (2.5) 6 13 ns 46, 52
tCK (2) 7.5 13 ns 46, 52
CL = 2
t t
CK low-level width CL 0.45 0.55 CK 31
t
DQ and DM input hold time relative to DQS DH 0.45 – ns 27, 32
tDIPW
DQ and DM input pulse width (for each input) 1.75 – ns 32
tDQSCK
Access window of DQS from CK/CK# –0.6 0.6 ns
t t
DQS input high pulse width DQSH 0.35 – CK
tDQSL tCK
DQS input low pulse width 0.35 –
tDQSQ – 0.4 ns 26, 27
DQS–DQ skew, DQS to last DQ valid, per group, per access
tDQSS 0.75 1.25 tCK
WRITE command to first DQS latching transition
tDS 0.45 – ns 27, 32
DQ and DM input setup time relative to DQS
t t
DQS falling edge from CK rising - hold time DSH 0.2 – CK
tDSS tCK
DQS falling edge to CK rising - setup time 0.2 –
tHP tCH, – ns 35
Half-clock period
tCL
t
Data-out High-Z window from CK/CK# HZ – 0.7 ns 19, 43
tIH 0.75 – ns
Address and control input hold time (fast slew rate) F
tIH
Address and control input hold time (slow slew rate) S 0.8 – ns 15
t
Address and control input pulse width (for each input) IPW 2.2 – ns
tIS
Address and control input setup time (fast slew rate) F 0.75 – ns
tIS 0.8 – ns 15
Address and control input setup time (slow slew rate) S
tLZ –0.7 – ns 19, 43
Data-out Low-Z window from CK/CK#
tMRD 12 – ns
LOAD MODE REGISTER command cycle time
tQH tHP -tQHS
DQ-DQS hold, DQS to first DQ to go non-valid, per access – ns 26, 27
tQHS
Data hold skew factor – 0.50 ns
tRAP 15 – ns
ACTIVE-to-READ with auto precharge command
tRAS
ACTIVE-to-PRECHARGE command 42 70,000 ns 36, 54
tRC
ACTIVE-to-ACTIVE/AUTO REFRESH command period 60 – ns 55
tRCD
ACTIVE-to-READ or WRITE delay 15 – ns
tREFC – 70.3 µs 24
REFRESH-to-REFRESH command interval (Industrial) AIT
tREFC – 17.55 µs 24
REFRESH-to-REFRESH command interval (Automotive) AAT
tREFI
Average periodic refresh interval (Industrial) AIT – 7.8 µs 24
tREFI
Average periodic refresh interval (Automotive) AAT – 1.95 µs 24
tRFC
AUTO REFRESH command period 72 – ns 50
tRP 15 – ns
PRECHARGE command period
tRPRE 0.9 1.1 tCK 44
DQS read preamble
tRPST tCK
DQS read postamble 0.4 0.6 44
t
ACTIVE bank a to ACTIVE bank b command RRD 12 – ns
t
Terminating voltage delay to VSS VTD 0 – ns
t t
DQS write preamble WPRE 0.25 – CK

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DDR_x4x8x16_Core2.fm - Core DDR Rev. B 11/11 EN 24 ©2011 Micron Technology, Inc. All rights reserved.
 256Mb: x8, x16 Automotive DDR SDRAM
Electrical Specifications – DC and AC

Table 17: Electrical Characteristics and Recommended AC Operating Conditions (-6) (continued)
Notes: 1–6, 16–18, 34 apply to the entire table; Notes appear on page 34;
0°C TA  70°C; VDDQ = 2.5V ±0.2V, VDD = 2.5V ±0.2V

AC Characteristics -6 (FBGA)
Parameter Symbol Min Max Units Notes
t
DQS write preamble setup time WPRES 0 – ns 21, 22
t t
DQS write postamble WPST 0.4 0.6 CK 20
t
Write recovery time WR 15 – ns
tWTR 1 – tCK
Internal WRITE-to-READ command delay
t
Exit SELF REFRESH-to-non-READ command XSNR 75 – ns
t t
Exit SELF REFRESH-to-READ command XSRD 200 – CK
– tQH - tDQSQ
Data valid output window ns 26

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DDR_x4x8x16_Core2.fm - Core DDR Rev. B 11/11 EN 25 ©2011 Micron Technology, Inc. All rights reserved.
 256Mb: x8, x16 Automotive DDR SDRAM
Electrical Specifications – DC and AC

Table 18: Electrical Characteristics and Recommended AC Operating Conditions (-6T)

Notes: 1–6, 16–18, 34 apply to the entire table; Notes appear on page 34;
0°C TA  70°C; VDDQ = 2.5V ±0.2V, VDD = 2.5V ±0.2V

AC Characteristics -6T (TSOP)

Parameter Symbol Min Max Units Notes
t
Access window of DQ from CK/CK# AC –0.70 0.70 ns
t t
CK high-level width CH 0.45 0.55 CK 31
t
Clock cycle time CL = 2.5 CK (2.5) 6 13 ns 46, 52
tCK (2) 7.5 13 ns 46, 52
CL = 2
t t
CK low-level width CL 0.45 0.55 CK 31
t
DQ and DM input hold time relative to DQS DH 0.45 – ns 27, 32
tDIPW
DQ and DM input pulse width (for each input) 1.75 – ns 32
tDQSCK
Access window of DQS from CK/CK# –0.6 0.6 ns
t t
DQS input high pulse width DQSH 0.35 – CK
tDQSL tCK
DQS input low pulse width 0.35 –
tDQSQ – 0.45 ns 26, 27
DQS–DQ skew, DQS to last DQ valid, per group, per access
tDQSS 0.75 1.25 tCK
WRITE command to first DQS latching transition
tDS 0.45 – ns 27, 32
DQ and DM input setup time relative to DQS
t t
DQS falling edge from CK rising - hold time DSH 0.2 – CK
tDSS tCK
DQS falling edge to CK rising - setup time 0.2 –
tHP tCH, – ns 35
Half-clock period
tCL
t
Data-out High-Z window from CK/CK# HZ – 0.7 ns 19, 43
tIH 0.75 – ns
Address and control input hold time (fast slew rate) F
tIH
Address and control input hold time (slow slew rate) S 0.8 – ns 15
t
Address and control input pulse width (for each input) IPW 2.2 – ns
tIS
Address and control input setup time (fast slew rate) F 0.75 – ns
tIS 0.8 – ns 15
Address and control input setup time (slow slew rate) S
tLZ –0.7 – ns 19, 43
Data-out Low-Z window from CK/CK#
tMRD 12 – ns
LOAD MODE REGISTER command cycle time
tQH tHP -tQHS
DQ-DQS hold, DQS to first DQ to go non-valid, per access – ns 26, 27
tQHS
Data hold skew factor – 0.55 ns
tRAP 15 – ns
ACTIVE-to-READ with auto precharge command
tRAS
ACTIVE-to-PRECHARGE command 42 70,000 ns 36, 54
tRC
ACTIVE-to-ACTIVE/AUTO REFRESH command period 60 – ns 55
tRCD
ACTIVE-to-READ or WRITE delay 15 – ns
tREFC – 70.3 µs 24
REFRESH-to-REFRESH command interval (Industrial) AIT
tREFC – 17.55 µs 24
REFRESH-to-REFRESH command interval (Automotive) AAT
tREFI
Average periodic refresh interval (Industrial) AIT – 7.8 µs 24
tREFI
Average periodic refresh interval (Automotive) AAT – 1.95 µs 24
tRP
PRECHARGE command period 15 – ns
tRPRE 0.9 1.1 tCK 44
DQS read preamble
tRPST 0.4 0.6 tCK 44
DQS read postamble
tRRD
ACTIVE bank a to ACTIVE bank b command 12 – ns
t
Terminating voltage delay to VSS VTD 0 – ns
tWPRE tCK
DQS write preamble 0.25 –
t
DQS write preamble setup time WPRES 0 – ns 21, 22

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DDR_x4x8x16_Core2.fm - Core DDR Rev. B 11/11 EN 26 ©2011 Micron Technology, Inc. All rights reserved.
 256Mb: x8, x16 Automotive DDR SDRAM
Electrical Specifications – DC and AC

Table 18: Electrical Characteristics and Recommended AC Operating Conditions (-6T) (continued)
Notes: 1–6, 16–18, 34 apply to the entire table; Notes appear on page 34;
0°C TA  70°C; VDDQ = 2.5V ±0.2V, VDD = 2.5V ±0.2V

AC Characteristics -6T (TSOP)

Parameter Symbol Min Max Units Notes
t t
DQS write postamble WPST 0.4 0.6 CK 20
t
Write recovery time WR 15 – ns
t t
Internal WRITE-to-READ command delay WTR 1 – CK
tXSNR 75 – ns
Exit SELF REFRESH-to-non-READ command
t t
Exit SELF REFRESH-to-READ command XSRD 200 – CK
– t t
Data valid output window QH - DQSQ ns 26

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DDR_x4x8x16_Core2.fm - Core DDR Rev. B 11/11 EN 27 ©2011 Micron Technology, Inc. All rights reserved.
 256Mb: x8, x16 Automotive DDR SDRAM
Electrical Specifications – DC and AC

Table 19: Electrical Characteristics and Recommended AC Operating Conditions (-75E)

Notes: 1–6, 16–18, 34 apply to the entire table; Notes appear on page 34;
0°C TA  70°C; VDDQ = 2.5V ±0.2V, VDD = 2.5V ±0.2V

AC Characteristics -75E
Parameter Symbol Min Max Units Notes
t
Access window of DQ from CK/CK# AC –0.75 0.75 ns
t t
CK high-level width CH 0.45 0.55 CK 31
t
Clock cycle time CL = 2.5 CK (2.5) 7.5 13 ns 46, 52
tCK (2) 7.5 13 ns 46, 52
CL = 2
t t
CK low-level width CL 0.45 0.55 CK 31
t
DQ and DM input hold time relative to DQS DH 0.5 – ns 27, 32
tDIPW
DQ and DM input pulse width (for each input) 1.75 – ns 32
tDQSCK
Access window of DQS from CK/CK# –0.75 0.75 ns
t t
DQS input high pulse width DQSH 0.35 – CK
tDQSL tCK
DQS input low pulse width 0.35 –
tDQSQ – 0.5 ns 26, 27
DQS–DQ skew, DQS to last DQ valid, per group, per access
tDQSS 0.75 1.25 tCK
WRITE command to first DQS latching transition
tDS 0.5 – ns 27, 32
DQ and DM input setup time relative to DQS
t t
DQS falling edge from CK rising - hold time DSH 0.2 – CK
tDSS tCK
DQS falling edge to CK rising - setup time 0.2 –
tHP tCH, – ns 35
Half-clock period
tCL
t
Data-out High-Z window from CK/CK# HZ – 0.75 ns 19, 43
tIH 0.90 – ns
Address and control input hold time (fast slew rate) F
tIH
Address and control input hold time (slow slew rate) S 1 – ns 15
t
Address and control input pulse width (for each input) IPW 2.2 – ns
tIS
Address and control input setup time (fast slew rate) F 0.90 – ns
tIS 1 – ns 15
Address and control input setup time (slow slew rate) S
tLZ –0.75 – ns 19, 43
Data-out Low-Z window from CK/CK#
tMRD 15 – ns
LOAD MODE REGISTER command cycle time
tQH tHP -tQHS
DQ-DQS hold, DQS to first DQ to go non-valid, per access – ns 26, 27
tQHS
Data hold skew factor – 0.75 ns
tRAP 15 – ns
ACTIVE-to-READ with auto precharge command
tRAS
ACTIVE-to-PRECHARGE command 40 120,000 ns 36, 54
tRC
ACTIVE-to-ACTIVE/AUTO REFRESH command period 60 – ns 55
tRCD
ACTIVE-to-READ or WRITE delay 15 – ns
tREFC – 70.3 µs 24
REFRESH-to-REFRESH command interval (Industrial) AIT
tREFC – 17.55 µs 24
REFRESH-to-REFRESH command interval (Automotive) AAT
tREFI
Average periodic refresh interval (Industrial) AIT – 7.8 µs 24
tREFI
Average periodic refresh interval (Automotive) AAT – 1.95 µs 24
tRFC
AUTO REFRESH command period 75 – ns 50
tRP 15 – ns
PRECHARGE command period
tRPRE 0.9 1.1 tCK 44
DQS read preamble
tRPST tCK
DQS read postamble 0.4 0.6 44
t
ACTIVE bank a to ACTIVE bank b command RRD 15 – ns
t
Terminating voltage delay to VSS VTD 0 – ns
t t
DQS write preamble WPRE 0.25 – CK

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DDR_x4x8x16_Core2.fm - Core DDR Rev. B 11/11 EN 28 ©2011 Micron Technology, Inc. All rights reserved.
 256Mb: x8, x16 Automotive DDR SDRAM
Electrical Specifications – DC and AC

Table 19: Electrical Characteristics and Recommended AC Operating Conditions (-75E) (continued)
Notes: 1–6, 16–18, 34 apply to the entire table; Notes appear on page 34;
0°C TA  70°C; VDDQ = 2.5V ±0.2V, VDD = 2.5V ±0.2V

AC Characteristics -75E
Parameter Symbol Min Max Units Notes
t
DQS write preamble setup time WPRES 0 – ns 21, 22
t t
DQS write postamble WPST 0.4 0.6 CK 20
t
Write recovery time WR 15 – ns
tWTR 1 – tCK
Internal WRITE-to-READ command delay
t
Exit SELF REFRESH-to-non-READ command XSNR 75 – ns
t t
Exit SELF REFRESH-to-READ command XSRD 200 – CK
– tQH - tDQSQ
Data valid output window ns 26

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 256Mb: x8, x16 Automotive DDR SDRAM
Electrical Specifications – DC and AC

Table 20: Electrical Characteristics and Recommended AC Operating Conditions (-75Z)

Notes: 1–6, 16–18, 34 apply to the entire table; Notes appear on page 34;
0°C TA  70°C; VDDQ = 2.5V ±0.2V, VDD = 2.5V ±0.2V

AC Characteristics -75Z
Parameter Symbol Min Max Units Notes
t
Access window of DQ from CK/CK# AC –0.75 0.75 ns
t t
CK high-level width CH 0.45 0.55 CK 31
t
Clock cycle time CL = 2.5 CK (2.5) 7.5 13 ns 46
tCK (2) 7.5 13 ns 46
CL = 2
t t
CK low-level width CL 0.45 0.55 CK 31
t
DQ and DM input hold time relative to DQS DH 0.5 – ns 27, 32
tDIPW
DQ and DM input pulse width (for each input) 1.75 – ns 32
tDQSCK
Access window of DQS from CK/CK# –0.75 0.75 ns
t t
DQS input high pulse width DQSH 0.35 – CK
tDQSL tCK
DQS input low pulse width 0.35 –
tDQSQ – 0.5 ns 26, 27
DQS–DQ skew, DQS to last DQ valid, per group, per access
tDQSS 0.75 1.25 tCK
WRITE command-to-first DQS latching transition
tDS 0.5 – ns 27, 32
DQ and DM input setup time relative to DQS
t t
DQS falling edge from CK rising – hold time DSH 0.2 – CK
tDSS tCK
DQS falling edge to CK rising – setup time 0.2 –
tHP tCH,tCL – ns 35
Half-clock period
t
Data-out High-Z window from CK/CK# HZ – 0.75 ns 19, 43
tIH 0.90 – ns
Address and control input hold time (fast slew rate) F
tIH
Address and control input hold time (slow slew rate) S 1 – ns 15
tIPW
Address and control input pulse width (for each input) 2.2 – ns
tIS 0.90 – ns
Address and control input setup time (fast slew rate) F
tIS 1 – ns 15
Address and control input setup time (slow slew rate) S
tLZ
Data-out Low-Z window from CK/CK# –0.75 – ns 19, 43
tMRD
LOAD MODE REGISTER command cycle time 15 – ns
tQH tHP -tQHS
DQ–DQS hold, DQS to first DQ to go non-valid, per access – ns 26, 27
tQHS – 0.75 ns
Data hold skew factor
tRAP
ACTIVE-to-READ with auto precharge command 20 – ns
t
ACTIVE-to-PRECHARGE command RAS 40 120,000 ns 36
tRC
ACTIVE-to-ACTIVE/AUTO REFRESH command period 65 – ns 55
tRCD 20 – ns
ACTIVE-to-READ or WRITE delay
tREFC
REFRESH-to-REFRESH command interval (Industrial) AIT – 70.3 µs 24
tREFC – 17.55 µs 24
REFRESH-to-REFRESH command interval (Automotive) AAT
t
Average periodic refresh interval (Industrial) REFIAIT – 7.8 µs 24
tREFI
Average periodic refresh interval (Automotive) AAT – 1.95 µs 24
tRFC 75 – ns 50
AUTO REFRESH command period
tRP
PRECHARGE command period 20 – ns
tRPRE 0.9 1.1 tCK 44
DQS read preamble
t t
DQS read postamble RPST 0.4 0.6 CK 44
t
ACTIVE bank a to ACTIVE bank b command RRD 15 – ns
t
Terminating voltage delay to VDD VTD 0 – ns
tWPRE 0.25 – tCK
DQS write preamble
tWPRES
DQS write preamble setup time 0 – ns 21, 22

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DDR_x4x8x16_Core2.fm - Core DDR Rev. B 11/11 EN 30 ©2011 Micron Technology, Inc. All rights reserved.
 256Mb: x8, x16 Automotive DDR SDRAM
Electrical Specifications – DC and AC

Table 20: Electrical Characteristics and Recommended AC Operating Conditions (-75Z) (continued)
Notes: 1–6, 16–18, 34 apply to the entire table; Notes appear on page 34;
0°C TA  70°C; VDDQ = 2.5V ±0.2V, VDD = 2.5V ±0.2V

AC Characteristics -75Z
Parameter Symbol Min Max Units Notes
t t
DQS write postamble WPST 0.4 0.6 CK 20
t
Write recovery time WR 15 – ns
t t
Internal WRITE-to-READ command delay WTR 1 – CK
tXSNR 75 – ns
Exit SELF REFRESH-to-non-READ command
t t
Exit SELF REFRESH-to-READ command XSRD 200 – CK
– t t
Data valid output window QH - DQSQ ns 26

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DDR_x4x8x16_Core2.fm - Core DDR Rev. B 11/11 EN 31 ©2011 Micron Technology, Inc. All rights reserved.
 256Mb: x8, x16 Automotive DDR SDRAM
Electrical Specifications – DC and AC

Table 21: Electrical Characteristics and Recommended AC Operating Conditions (-75)

Notes: 1–6, 16–18, 34 apply to the entire table; Notes appear on page 34;
0°C TA  70°C; VDDQ = 2.5V ±0.2V, VDD = 2.5V ±0.2V

AC Characteristics -75
Parameter Symbol Min Max Units Notes
t
Access window of DQ from CK/CK# AC –0.75 0.75 ns
t t
CK high-level width CH 0.45 0.55 CK 31
t
Clock cycle time CL = 2.5 CK (2.5) 7.5 13 ns 46
tCK (2) 10 13 ns 46
CL = 2
t t
CK low-level width CL 0.45 0.55 CK 31
t
DQ and DM input hold time relative to DQS DH 0.5 – ns 27, 32
tDIPW
DQ and DM input pulse width (for each input) 1.75 – ns 32
tDQSCK
Access window of DQS from CK/CK# –0.75 0.75 ns
t t
DQS input high pulse width DQSH 0.35 – CK
tDQSL tCK
DQS input low pulse width 0.35 –
tDQSQ – 0.5 ns 26, 27
DQS–DQ skew, DQS to last DQ valid, per group, per access
tDQSS 0.75 1.25 tCK
WRITE command-to-first DQS latching transition
tDS 0.5 – ns 27, 32
DQ and DM input setup time relative to DQS
t t
DQS falling edge from CK rising – hold time DSH 0.2 – CK
tDSS tCK
DQS falling edge to CK rising – setup time 0.2 –
tHP tCH,tCL – ns 35
Half-clock period
t
Data-out High-Z window from CK/CK# HZ – 0.75 ns 19, 43
tIH 0.90 – ns
Address and control input hold time (fast slew rate) F
tIH
Address and control input hold time (slow slew rate) S 1 – ns 15
tIPW
Address and control input pulse width (for each input) 2.2 – ns
tIS 0.90 – ns
Address and control input setup time (fast slew rate) F
tIS 1 – ns 15
Address and control input setup time (slow slew rate) S
tLZ
Data-out Low-Z window from CK/CK# –0.75 – ns 19, 43
tMRD
LOAD MODE REGISTER command cycle time 15 – ns
tQH tHP -tQHS
DQ–DQS hold, DQS to first DQ to go non-valid, per access – ns 26, 27
tQHS – 0.75 ns
Data hold skew factor
tRAP
ACTIVE-to-READ with auto precharge command 20 – ns
t
ACTIVE-to-PRECHARGE command RAS 40 120,000 ns 36
tRC
ACTIVE-to-ACTIVE/AUTO REFRESH command period 65 – ns 55
tRCD 20 – ns
ACTIVE-to-READ or WRITE delay
tREFC
REFRESH-to-REFRESH command interval (Industrial) AIT – 70.3 µs 24
tREFC – 17.55 µs 24
REFRESH-to-REFRESH command interval (Automotive) AAT
t
Average periodic refresh interval (Industrial) REFIAIT – 7.8 µs 24
tREFI
Average periodic refresh interval (Automotive) AAT – 1.95 µs 24
trFC 75 – ns 50
AUTO REFRESH command period
tRP
PRECHARGE command period 20 – ns
tRPRE 0.9 1.1 tCK 44
DQS read preamble
t
DQS read postamble RPST 0.4 0.6 tCK 44
t
ACTIVE bank a to ACTIVE bank b command RRD 15 – ns
t
Terminating voltage delay to VDD VTD 0 – ns
tWPRE 0.25 – tCK
DQS write preamble
tWPRES
DQS write preamble setup time 0 – ns 21, 22

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Electrical Specifications – DC and AC

Table 21: Electrical Characteristics and Recommended AC Operating Conditions (-75) (continued)
Notes: 1–6, 16–18, 34 apply to the entire table; Notes appear on page 34;
0°C TA  70°C; VDDQ = 2.5V ±0.2V, VDD = 2.5V ±0.2V

AC Characteristics -75
Parameter Symbol Min Max Units Notes
DQS write postamble tWPST 0.4 0.6 tCK 20
Write recovery time tWR 15 – ns
t t
Internal WRITE-to-READ command delay WTR 1 – CK
tXSNR 75 – ns
Exit SELF REFRESH-to-non-READ command
t t
Exit SELF REFRESH-to-READ command XSRD 200 – CK
– t t
Data valid output window QH - DQSQ ns 26

Table 22: Input Slew Rate Derating Values for Addresses and Commands
Note: 15 applies to the entire table; Notes appear on page 34;
0°C TA  70°C; VDDQ = 2.5V ±0.2V, VDD = 2.5V ±0.2V

tIS tIH
Speed Slew Rate Units
-75Z/-75E 0.500 V/ns 1.00 1 ns
-75Z/-75E 0.400 V/ns 1.05 1 ns
-75Z/-75E 0.300 V/ns 1.10 1 ns

Table 23: Input Slew Rate Derating Values for DQ, DQS, and DM
Note: 32 applies to the entire table; Notes appear on page 34;
0°C TA  70°C; VDDQ = 2.5V ±0.2V, VDD = 2.5V ±0.2V

tDS tDH
Speed Slew Rate Units
-75Z/-75E 0.500 V/ns 0.50 0.50 ns
-75Z/-75E 0.400 V/ns 0.55 0.55 ns
-75Z/-75E 0.300 V/ns 0.60 0.60 ns

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Electrical Specifications – DC and AC

Notes
1. All voltages referenced to VSS.
2. Tests for AC timing, IDD, and electrical AC and DC characteristics may be conducted
at nominal reference/supply voltage levels, but the related specifications and the
device operation are guaranteed for the full voltage range specified.
3. Outputs (except for IDD measurements) measured with equivalent load:

VTT
50
Output Reference
point
(VOUT)
30pF

4. AC timing and IDD tests may use a VIL-to-VIH swing of up to 1.5V in the test environ-
ment, but input timing is still referenced to VREF (or to the crossing point for CK/CK#),
and parameter specifications are guaranteed for the specified AC input levels under
normal use conditions. The minimum slew rate for the input signals used to test the
device is 1 V/ns in the range between VIL(AC) and VIH(AC).
5. The AC and DC input level specifications are as defined in the SSTL_2 standard (that
is, the receiver will effectively switch as a result of the signal crossing the AC input
level and will remain in that state as long as the signal does not ring back above
[below] the DC input LOW [HIGH] level).
6. All speed grades are not offered on all densities. Refer to page 1 for availability.
7. VREF is expected to equal VDDQ/2 of the transmitting device and to track variations in
the DC level of the same. Peak-to-peak noise (noncommon mode) on VREF may not
exceed ±2% of the DC value. Thus, from VDDQ/2, VREF is allowed ±25mV for DC error
and an additional ±25mV for AC noise. This measurement is to be taken at the nearest
VREF bypass capacitor.
8. VTT is not applied directly to the device. VTT is a system supply for signal termination
resistors, it is expected to be set equal to VREF, and it must track variations in the DC
level of VREF.
9. VID is the magnitude of the difference between the input level on CK and the input
level on CK#.
10. The value of VIX and VMP is expected to equal VDDQ/2 of the transmitting device and
must track variations in the DC level of the same.
11. IDD is dependent on output loading and cycle rates. Specified values are obtained
with minimum cycle times at CL = 3 for -5B; CL = 2.5, -6/-6T/-75; and CL = 2,
-75E/-75Z speeds with the outputs open.
12. Enables on-chip refresh and address counters.
13. IDD specifications are tested after the device is properly initialized and is averaged at
the defined cycle rate.
14. This parameter is sampled. VDD = 2.5V ±0.2V, VDDQ = 2.5V ±0.2V, VREF = VSS,
f = 100 MHz, TA = 25°C, VOUT(DC) = VDDQ/2, VOUT (peak-to-peak) = 0.2V. DM input is
grouped with I/O pins, reflecting the fact that they are matched in loading.
15. For slew rates less than 1 V/ns and greater than or equal to 0.5 V/ns. If the slew rate is
less than 0.5 V/ns, timing must be derated: tIS has an additional 50ps per each
100 mV/ns reduction in slew rate from the 500 mV/ns. tIH has 0ps added, that is, it
remains constant. If the slew rate exceeds 4.5 V/ns, functionality is uncertain. For -5B,
-6, and -6T, slew rates must be greater than or equal to 0.5 V/ns.

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Electrical Specifications – DC and AC

16. The CK/CK# input reference level (for timing referenced to CK/CK#) is the point at
which CK and CK# cross; the input reference level for signals other than CK/CK# is
VREF.
17. Inputs are not recognized as valid until VREF stabilizes. Once initialized, including self
refresh mode, VREF must be powered within specified range. Exception: during the
period before VREF stabilizes, CKE < 0.3 × VDD is recognized as LOW.
18. The output timing reference level, as measured at the timing reference point (indi-
cated in Note 3), is VTT.
19. tHZ and tLZ transitions occur in the same access time windows as data valid transi-
tions. These parameters are not referenced to a specific voltage level, but specify
when the device output is no longer driving (High-Z) or begins driving (Low-Z).
20. The intent of the “Don’t Care” state after completion of the postamble is the DQS-
driven signal should either be HIGH, LOW, or High-Z, and that any signal transition
within the input switching region must follow valid input requirements. That is, if
DQS transitions HIGH (above VIH(DC)min then it must not transition LOW (below
VIH(DC) prior to tDQSH [MIN]).
21. This is not a device limit. The device will operate with a negative value, but system
performance could be degraded due to bus turnaround.
22. It is recommended that DQS be valid (HIGH or LOW) on or before the WRITE com-
mand. The case shown (DQS going from High-Z to logic LOW) applies when no
WRITEs were previously in progress on the bus. If a previous WRITE was in progress,
DQS could be HIGH during this time, depending on tDQSS.
23. MIN (tRC or tRFC) for IDD measurements is the smallest multiple of tCK that meets
the minimum absolute value for the respective parameter. tRAS (MAX) for IDD mea-
surements is the largest multiple of tCK that meets the maximum absolute value for
t
RAS.
24. The refresh period is 64ms (AIT) or 16ms (AAT). This equates to an average refresh
rate of 7.8125µs (AIT) or 1.95us (AAT). However, an AUTO REFRESH command must
be asserted at least once every 70.3µs (AIT) or 17.55µs (AAT); burst refreshing or post-
ing by the DRAM controller greater than 8 REFRESH cycles is not allowed.
25. The I/O capacitance per DQS and DQ byte/group will not differ by more than this
maximum amount for any given device.
26. The data valid window is derived by achieving other specifications: tHP (tCK/2),
tDQSQ, and tQH (tQH = tHP - tQHS). The data valid window derates in direct propor-
tion to the clock duty cycle and a practical data valid window can be derived. The
clock is allowed a maximum duty cycle variation of 45/55, because functionality is
uncertain when operating beyond a 45/55 ratio. The data valid window derating
curves are provided in Figure 11 on page 36 for duty cycles ranging between 50/50
and 45/55.
27. Referenced to each output group: x8 = DQS with DQ[7:0]; x16 = LDQS with DQ[7:0]
and UDQS with DQ[15:8].
28. This limit is actually a nominal value and does not result in a fail value. CKE is HIGH
during the REFRESH command period (tRFC [MIN]), else CKE is LOW (that is, during
standby).
29. To maintain a valid level, the transitioning edge of the input must:
29a. Sustain a constant slew rate from the current AC level through to the target AC
level, VIL(AC) or VIH(AC).
29b. Reach at least the target AC level.
29c. After the AC target level is reached, continue to maintain at least the target DC
level, VIL(DC) or VIH(DC).

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Electrical Specifications – DC and AC

30. The input capacitance per pin group will not differ by more than this maximum
amount for any given device.
31. CK and CK# input slew rate must be 1 V/ns (2 V/ns if measured differentially).

Figure 11: Derating Data Valid Window (tQH – tDQSQ)

-6T @ tCK = 7.5ns

-75E / -75 @ tCK = 7.5ns
3.0ns
-6 @ tCK = 6ns
2.75
2.71
2.68
-6T @ tCK = 6ns
2.64
2.60
2.56 -5B @ tCK = 5ns
2.53
2.50 2.49
2.5ns 2.46
2.43
2.45
2.41
2.39 2.38
2.35
Data Valid Window

2.31
2.28
2.24
2.20
2.16
2.13
2.10 2.07
2.04
2.01
2.0ns 1.98
1.95
1.92
2.00 1.89 1.86
1.97 1.83
1.94 1.80
1.91
1.88
1.85
1.82
1.79 1.76
1.73
1.70
1.5ns 1.60 1.58
1.55
1.53 1.50 1.48 1.45
1.43 1.40 1.38
1.35

1.0ns
50/50 49/51 48/53 47/53 46/54 45/55

Clock Duty Cycle

32. DQ and DM input slew rates must not deviate from DQS by more than 10%. If the DQ/
DM/DQS slew rate is less than 0.5 V/ns, timing must be derated: 50ps must be added
to tDS and tDH for each 100 mV/ns reduction in slew rate. For -5B, -6, and
-6T speed grades, the slew rate must be 0.5 V/ns. If the slew rate exceeds 4 V/ns,
functionality is uncertain.
33. VDD must not vary more than 4% if CKE is not active while any bank is active.
34. The clock is allowed up to ±150ps of jitter. Each timing parameter is allowed to vary by
the same amount.
35. tHP (MIN) is the lesser of tCL (MIN) and tCH (MIN) actually applied to the device CK
and CK# inputs, collectively, during bank active.
36. READs and WRITEs with auto precharge are not allowed to be issued until tRAS (MIN)
can be satisfied prior to the internal PRECHARGE command being issued.
37. Any positive glitch must be less than 1/3 of the clock cycle and not more than 400mV
or 2.9V (300mV or 2.9V maximum for -5B), whichever is less. Any negative glitch must
be less than 1/3 of the clock cycle and not exceed either –300mV or 2.2V (2.4V for -5B),
whichever is more positive. The average cannot be below the 2.5V (2.6V for -5B) mini-
mum.
38. Normal output drive curves:
38a. The full driver pull-down current variation from MIN to MAX process; tempera-
ture and voltage will lie within the outer bounding lines of the V-I curve of
Figure 12 on page 37.
38b. The driver pull-down current variation, within nominal voltage and temperature
limits, is expected, but not guaranteed, to lie within the inner bounding lines of
the V-I curve of Figure 12 on page 37.

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Electrical Specifications – DC and AC

38c. The full driver pull-up current variation from MIN to MAX process; temperature
and voltage will lie within the outer bounding lines of the V-I curve of Figure 13 on
page 37.
38d. The driver pull-up current variation within nominal limits of voltage and temper-
ature is expected, but not guaranteed, to lie within the inner bounding lines of the
V-I curve of Figure 13 on page 37.
38e. The full ratio variation of MAX to MIN pull-up and pull-down current should be
between 0.71 and 1.4 for drain-to-source voltages from 0.1V to 1.0V at the same
voltage and temperature.
38f. The full ratio variation of the nominal pull-up to pull-down current should be
unity ±10% for device drain-to-source voltages from 0.1V to 1.0V.

Figure 12: Full Drive Pull-Down Characteristics

160

140

120

100
IOUT (mA)

80

60

40

20

0
0.0 0.5 1.0 1.5 2.0 2.5

VOUT (V)

Figure 13: Full Drive Pull-Up Characteristics

-20

-40

-60
IOUT (mA)

-80

-100

-120

-140

-160

-180

-200
0.0 0.5 1.0 1.5 2.0 2.5
VDDQ - VOUT (V)

39. Reduced output drive curves:

39a. The full driver pull-down current variation from MIN to MAX process; tempera-
ture and voltage will lie within the outer bounding lines of the V-I curve of
Figure 14 on page 38.
39b. The driver pull-down current variation, within nominal voltage and temperature
limits, is expected, but not guaranteed, to lie within the inner bounding lines of
the V-I curve of Figure 14 on page 38.
39c. The full driver pull-up current variation from MIN to MAX process; temperature
and voltage will lie within the outer bounding lines of the V-I curve of Figure 15.

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Electrical Specifications – DC and AC

39d. The driver pull-up current variation, within nominal voltage and temperature
limits, is expected, but not guaranteed, to lie within the inner bounding lines of
the V-I curve of Figure 15 on page 38.
39e. The full ratio variation of the MAX-to-MIN pull-up and pull-down current should
be between 0.71 and 1.4 for device drain-to-source voltages from 0.1V to 1.0V at
the same voltage and temperature.
39f. The full ratio variation of the nominal pull-up to pull-down current should be
unity ±10%, for device drain-to-source voltages from 0.1V to 1.0V.

Figure 14: Reduced Drive Pull-Down Characteristics

80

70

60

50
IOUT (mA)

40

30

20

10

0
0.0 0.5 1.0 1.5 2.0 2.5
VOUT (V)

Figure 15: Reduced Drive Pull-Up Characteristics

0

-10

-20

-30
IOUT (mA)

-40

-50

-60

-70

-80
0.0 0.5 1.0 1.5 2.0 2.5

VDDQ - VOUT (V)

40. The voltage levels used are derived from a minimum VDD level and the referenced test
load. In practice, the voltage levels obtained from a properly terminated bus will pro-
vide significantly different voltage values.
41. VIH overshoot: VIH,max = VDDQ + 1.5V for a pulse width 3ns, and the pulse width
can not be greater than 1/3 of the cycle rate. VIL undershoot: VIL,min = –1.5V for a pulse
width 3ns, and the pulse width can not be greater than 1/3 of the cycle rate.
42. VDD and VDDQ must track each other.
43. tHZ (MAX) will prevail over tDQSCK (MAX) + tRPST (MAX) condition. tLZ (MIN) will
prevail over tDQSCK (MIN) + tRPRE (MAX) condition.

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Electrical Specifications – DC and AC

44. tRPST end point and tRPRE begin point are not referenced to a specific voltage level
but specify when the device output is no longer driving (tRPST) or begins driving
(tRPRE).
45. During initialization, VDDQ, VTT, and VREF must be equal to or less than VDD + 0.3V.
Alternatively, VTT may be 1.35V maximum during power-up, even if VDD/VDDQ are 0V,
provided a minimum of 42 of series resistance is used between the VTT supply and
the input pin.
46. The current Micron part operates below 83 MHz (slowest specified JEDEC operating
frequency). As such, future die may not reflect this option.
47. When an input signal is HIGH or LOW, it is defined as a steady state logic HIGH or
LOW.
48. Random address is changing; 50% of data is changing at every transfer.
49. Random address is changing; 100% of data is changing at every transfer.
50. CKE must be active (HIGH) during the entire time a REFRESH command is executed.
That is, from the time the AUTO REFRESH command is registered, CKE must be
active at each rising clock edge, until tRFC has been satisfied.
51. IDD2N specifies the DQ, DQS, and DM to be driven to a valid HIGH or LOW logic level.
IDD2Q is similar to IDD2F except IDD2Q specifies the address and control inputs to
remain stable. Although IDD2F, IDD2N, and IDD2Q are similar, IDD2F is “worst case.”
52. Whenever the operating frequency is altered, not including jitter, the DLL is required
to be reset followed by 200 clock cycles before any READ command.
53. This is the DC voltage supplied at the DRAM and is inclusive of all noise up to 20 MHz.
Any noise above 20 MHz at the DRAM generated from any source other than that of
the DRAM itself may not exceed the DC voltage range of 2.6V ±100mV.
54. The -6/-6T speed grades will operate with tRAS (MIN) = 40ns and
t
RAS (MAX) = 120,000ns at any slower frequency.
55. DRAM devices should be evenly addressed when being accessed. Disproportionate
accesses to a particular row address may result in reduction of the product lifetime.

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Electrical Specifications – DC and AC

Table 24: Normal Output Drive Characteristics

Characteristics are specified under best, worst, and nominal process variation/conditions

Pull-Down Current (mA) Pull-Up Current (mA)

Voltage Nominal Nominal Nominal Nominal
(V) Low High Min Max Low High Min Max
0.1 6.0 6.8 4.6 9.6 –6.1 –7.6 –4.6 –10.0
0.2 12.2 13.5 9.2 18.2 –12.2 –14.5 –9.2 –20.0
0.3 18.1 20.1 13.8 26.0 –18.1 –21.2 –13.8 –29.8
0.4 24.1 26.6 18.4 33.9 –24.0 –27.7 –18.4 –38.8
0.5 29.8 33.0 23.0 41.8 –29.8 –34.1 –23.0 –46.8
0.6 34.6 39.1 27.7 49.4 –34.3 –40.5 –27.7 –54.4
0.7 39.4 44.2 32.2 56.8 –38.1 –46.9 –32.2 –61.8
0.8 43.7 49.8 36.8 63.2 –41.1 –53.1 –36.0 –69.5
0.9 47.5 55.2 39.6 69.9 –43.8 –59.4 –38.2 –77.3
1.0 51.3 60.3 42.6 76.3 –46.0 –65.5 –38.7 –85.2
1.1 54.1 65.2 44.8 82.5 –47.8 –71.6 –39.0 –93.0
1.2 56.2 69.9 46.2 88.3 –49.2 –77.6 –39.2 –100.6
1.3 57.9 74.2 47.1 93.8 –50.0 –83.6 –39.4 –108.1
1.4 59.3 78.4 47.4 99.1 –50.5 –89.7 –39.6 –115.5
1.5 60.1 82.3 47.7 103.8 –50.7 –95.5 –39.9 –123.0
1.6 60.5 85.9 48.0 108.4 –51.0 –101.3 –40.1 –130.4
1.7 61.0 89.1 48.4 112.1 –51.1 –107.1 –40.2 –136.7
1.8 61.5 92.2 48.9 115.9 –51.3 –112.4 –40.3 –144.2
1.9 62.0 95.3 49.1 119.6 –51.5 –118.7 –40.4 –150.5
2.0 62.5 97.2 49.4 123.3 –51.6 –124.0 –40.5 –156.9
2.1 62.8 99.1 49.6 126.5 –51.8 –129.3 –40.6 –163.2
2.2 63.3 100.9 49.8 129.5 –52.0 –134.6 –40.7 –169.6
2.3 63.8 101.9 49.9 132.4 –52.2 –139.9 –40.8 –176.0
2.4 64.1 102.8 50.0 135.0 –52.3 –145.2 –40.9 –181.3
2.5 64.6 103.8 50.2 137.3 –52.5 –150.5 –41.0 –187.6
2.6 64.8 104.6 50.4 139.2 –52.7 –155.3 –41.1 –192.9
2.7 65.0 105.4 50.5 140.8 –52.8 –160.1 –41.2 –198.2

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Electrical Specifications – DC and AC

Table 25: Reduced Output Drive Characteristics

Characteristics are specified under best, worst, and nominal process variation/conditions

Pull-Down Current (mA) Pull-Up Current (mA)

Voltage Nominal Nominal Nominal Nominal
(V) Low High Min Max Low High Min Max
0.1 3.4 3.8 2.6 5.0 –3.5 –4.3 –2.6 –5.0
0.2 6.9 7.6 5.2 9.9 –6.9 –7.8 –5.2 –9.9
0.3 10.3 11.4 7.8 14.6 –10.3 –12.0 –7.8 –14.6
0.4 13.6 15.1 10.4 19.2 –13.6 –15.7 –10.4 –19.2
0.5 16.9 18.7 13.0 23.6 –16.9 –19.3 –13.0 –23.6
0.6 19.9 22.1 15.7 28.0 –19.4 –22.9 –15.7 –28.0
0.7 22.3 25.0 18.2 32.2 –21.5 –26.5 –18.2 –32.2
0.8 24.7 28.2 20.8 35.8 –23.3 –30.1 –20.4 –35.8
0.9 26.9 31.3 22.4 39.5 –24.8 –33.6 –21.6 –39.5
1.0 29.0 34.1 24.1 43.2 –26.0 –37.1 –21.9 –43.2
1.1 30.6 36.9 25.4 46.7 –27.1 –40.3 –22.1 –46.7
1.2 31.8 39.5 26.2 50.0 –27.8 –43.1 –22.2 –50.0
1.3 32.8 42.0 26.6 53.1 –28.3 –45.8 –22.3 –53.1
1.4 33.5 44.4 26.8 56.1 –28.6 –48.4 –22.4 –56.1
1.5 34.0 46.6 27.0 58.7 –28.7 –50.7 –22.6 –58.7
1.6 34.3 48.6 27.2 61.4 –28.9 –52.9 –22.7 –61.4
1.7 34.5 50.5 27.4 63.5 –28.9 –55.0 –22.7 –63.5
1.8 34.8 52.2 27.7 65.6 –29.0 –56.8 –22.8 –65.6
1.9 35.1 53.9 27.8 67.7 –29.2 –58.7 –22.9 –67.7
2.0 35.4 55.0 28.0 69.8 –29.2 –60.0 –22.9 –69.8
2.1 35.6 56.1 28.1 71.6 –29.3 –61.2 –23.0 –71.6
2.2 35.8 57.1 28.2 73.3 –29.5 –62.4 –23.0 –73.3
2.3 36.1 57.7 28.3 74.9 –29.5 –63.1 –23.1 –74.9
2.4 36.3 58.2 28.3 76.4 –29.6 –63.8 –23.2 –76.4
2.5 36.5 58.7 28.4 77.7 –29.7 –64.4 –23.2 –77.7
2.6 36.7 59.2 28.5 78.8 –29.8 –65.1 –23.3 –78.8
2.7 36.8 59.6 28.6 79.7 –29.9 –65.8 –23.3 –79.7

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Commands

Commands
Tables 26 and 27 provide a quick reference of available commands. Two additional Truth
Tables—Table 28 on page 43 and Table 29 on page 44—provide current state/next state
information.

Table 26: Truth Table 1 – Commands

CKE is HIGH for all commands shown except SELF REFRESH; All states and sequences not shown are illegal or
reserved

Function CS# RAS# CAS# WE# Address Notes

DESELECT H X X X X 1
NO OPERATION (NOP) L H H H X 1
ACTIVE (select bank and activate row) L L H H Bank/row 2
READ (select bank and column and start READ burst) L H L H Bank/col 3
WRITE (select bank and column and start WRITE burst) L H L L Bank/col 3
BURST TERMINATE L H H L X 4
PRECHARGE (deactivate row in bank or banks) L L H L Code 5
AUTO REFRESH or SELF REFRESH L L L H X 6, 7
(enter self refresh mode)
LOAD MODE REGISTER L L L L Op-code 8

Notes: 1. DESELECT and NOP are functionally interchangeable.

2. BA[1:0] provide bank address and A[n:0] (128Mb: n = 11; 256Mb and 512Mb: n = 12; 1Gb: n
= 13) provide row address.
3. BA[1:0] provide bank address; A[i:0] provide column address, (where Ai is the most signifi-
cant column address bit for a given density and configuration, see Table 2 on page 2) A10
HIGH enables the auto precharge feature (non persistent), and A10 LOW disables the auto
precharge feature.
4. Applies only to READ bursts with auto precharge disabled; this command is undefined (and
should not be used) for READ bursts with auto precharge enabled and for WRITE bursts.
5. A10 LOW: BA[1:0] determine which bank is precharged. A10 HIGH: all banks are precharged
and BA[1:0] are “Don’t Care.”
6. This command is AUTO REFRESH if CKE is HIGH; SELF REFRESH if CKE is LOW.
7. Internal refresh counter controls row addressing while in self refresh mode, all inputs and
I/Os are “Don’t Care” except for CKE.
8. BA[1:0] select either the mode register or the extended mode register (BA0 = 0, BA1 = 0
select the mode register; BA0 = 1, BA1 = 0 select extended mode register; other combina-
tions of BA[1:0] are reserved). A[n:0] provide the op-code to be written to the selected
mode register.

Table 27: Truth Table 2 – DM Operation

Used to mask write data, provided coincident with the corresponding data

Name (Function) DM DQ
Write enable L Valid
Write inhibit H X

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Commands

Table 28: Truth Table 3 – Current State Bank n – Command to Bank n

Notes: 1–6 apply to the entire table; Notes appear below

Current State CS# RAS# CAS# WE# Command/Action Notes

Any H X X X DESELECT (NOP/continue previous operation)
L H H H NO OPERATION (NOP/continue previous operation)
Idle L L H H ACTIVE (select and activate row)
L L L H AUTO REFRESH 7
L L L L LOAD MODE REGISTER 7
Row active L H L H READ (select column and start READ burst) 10
L H L L WRITE (select column and start WRITE burst) 10
L L H L PRECHARGE (deactivate row in bank or banks) 8
Read L H L H READ (select column and start new READ burst) 10
(auto precharge L H L L WRITE (select column and start WRITE burst) 10, 12
disabled) L L H L PRECHARGE (truncate READ burst, start PRECHARGE) 8
L H H L BURST TERMINATE 9
Write L H L H READ (select column and start READ burst) 10, 11
(auto precharge L H L L WRITE (select column and start new WRITE burst) 10
disabled) L L H L PRECHARGE (truncate WRITE burst, start 8, 11
PRECHARGE)
Notes: 1. This table applies when CKEn-1 was HIGH and CKEn is HIGH (see Table 31 on page 46) and
after tXSNR has been met (if the previous state was self refresh).
2. This table is bank-specific, except where noted (that is, the current state is for a specific
bank and the commands shown are those allowed to be issued to that bank when in that
state). Exceptions are covered in the notes below.
3. Current state definitions:
• Idle: The bank has been precharged, and tRP has been met.
• Row active: A row in the bank has been activated, and tRCD has been met. No data
bursts/accesses and no register accesses are in progress.
• Read: A READ burst has been initiated, with auto precharge disabled, and has not yet
terminated or been terminated.
• Write: A WRITE burst has been initiated, with auto precharge disabled, and has not yet
terminated or been terminated.
4. The following states must not be interrupted by a command issued to the same bank. COM-
MAND INHIBIT or NOP commands, or allowable commands to the other bank should be
issued on any clock edge occurring during these states. Allowable commands to the other
bank are determined by its current state and Table 28 and according to Table 29 on
page 44.
• Precharging: Starts with registration of a PRECHARGE command and ends when tRP is
met. Once tRP is met, the bank will be in the idle state.
• Row activating: Starts with registration of an ACTIVE command and ends when tRCD is
met. Once tRCD is met, the bank will be in the “row active” state.
• Read with auto precharge enabled: Starts with registration of a READ command with
auto precharge enabled and ends when tRP has been met. Once tRP is met, the bank
will be in the idle state.
• Write with auto precharge enabled: Starts with registration of a WRITE command with
auto precharge enabled and ends when tRP has been met. Once tRP is met, the bank
will be in the idle state.
5. The following states must not be interrupted by any executable command; COMMAND
INHIBIT or NOP commands must be applied on each positive clock edge during these states.

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Commands

• Refreshing: Starts with registration of an AUTO REFRESH command and ends when tRFC
is met. Once tRFC is met, the DDR SDRAM will be in the all banks idle state.
• Accessing mode register: Starts with registration of an LMR command and ends when
tMRD has been met. Once tMRD is met, the DDR SDRAM will be in the all banks idle

state.
• Precharging all: Starts with registration of a PRECHARGE ALL command and ends when
t
RP is met. Once tRP is met, all banks will be in the idle state.
6. All states and sequences not shown are illegal or reserved.
7. Not bank-specific; requires that all banks are idle, and bursts are not in progress.
8. May or may not be bank-specific; if multiple banks are to be precharged, each must be in a
valid state for precharging.
9. Not bank-specific; BURST TERMINATE affects the most recent READ burst, regardless of
bank.
10. READs or WRITEs listed in the Command/Action column include READs or WRITEs with auto
precharge enabled and READs or WRITEs with auto precharge disabled.
11. Requires appropriate DM masking.
12. A WRITE command may be applied after the completion of the READ burst; otherwise, a
BURST TERMINATE must be used to end the READ burst prior to asserting a WRITE com-
mand.

Table 29: Truth Table 4 – Current State Bank n – Command to Bank m

Notes: 1–6 apply to the entire table; Notes appear on page 44

Current State CS# RAS# CAS# WE# Command/Action Notes

Any H X X X DESELECT (NOP/continue previous operation)
L H H H NO OPERATION (NOP/continue previous operation)
Idle X X X X Any command otherwise allowed to bank m
Row activating, active, L L H H ACTIVE (select and activate row)
or precharging L H L H READ (select column and start READ burst) 7
L H L L WRITE (select column and start WRITE burst) 7
L L H L PRECHARGE
Read (auto precharge L L H H ACTIVE (select and activate row)
disabled) L H L H READ (select column and start new READ burst) 7
L H L L WRITE (select column and start WRITE burst) 7, 9
L L H L PRECHARGE
Write (auto precharge L L H H ACTIVE (select and activate row)
disabled) L H L H READ (select column and start READ burst) 7, 8
L H L L WRITE (select column and start new WRITE burst) 7
L L H L PRECHARGE
Read (with auto- L L H H ACTIVE (select and activate row)
precharge) L H L H READ (select column and start new READ burst) 7
L H L L WRITE (select column and start WRITE burst) 7, 9
L L H L PRECHARGE
Write (with auto- L L H H ACTIVE (select and activate row)
precharge) L H L H READ (select column and start READ burst) 7
L H L L WRITE (select column and start new WRITE burst) 7
L L H L PRECHARGE
Notes: 1. This table applies when CKEn-1 was HIGH and CKEn is HIGH (see Table 31 on page 46) and
after tXSNR has been met (if the previous state was self refresh).

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Commands

2. This table describes alternate bank operation, except where noted (that is, the current state
is for bank n, and the commands shown are those allowed to be issued to bank m, assuming
that bank m is in such a state that the given command is allowable). Exceptions are covered
in the notes below.
3. Current state definitions:
• Idle: The bank has been precharged, and tRP has been met.
• Row active: A row in the bank has been activated, and tRCD has been met. No data
bursts/accesses and no register accesses are in progress.
• Read: A READ burst has been initiated, with auto precharge disabled, and has not yet
terminated or been terminated.
• Write: A WRITE burst has been initiated, with auto precharge disabled, and has not yet
terminated or been terminated.
• Read with auto precharge enabled: See note 3a below.
• Write with auto precharge enabled: See note 3a below.
a. The read with auto precharge enabled or write with auto precharge enabled states
can each be broken into two parts: the access period and the precharge period. For
read with auto precharge, the precharge period is defined as if the same burst was
executed with auto precharge disabled and then followed with the earliest possible
PRECHARGE command that still accesses all of the data in the burst. For write with
auto precharge, the precharge period begins when tWR ends, with tWR measured as
if auto precharge was disabled. The access period starts with registration of the com-
mand and ends where the precharge period (or tRP) begins. This device supports
concurrent auto precharge such that when a read with auto precharge is enabled or
a write with auto precharge is enabled, any command to other banks is allowed, as
long as that command does not interrupt the read or write data transfer already in
process. In either case, all other related limitations apply (for example, contention
between read data and write data must be avoided).
b. The minimum delay from a READ or WRITE command with auto precharge enabled,
to a command to a different bank is summarized in Table 30.

Table 30: Command Delays

CLRU = CL rounded up to the next integer

From Minimum Delay

Command To Command with Concurrent Auto Precharge
WRITE with auto READ or READ with auto precharge [1 + (BL/2)] × tCK + tWTR
precharge WRITE or WRITE with auto precharge (BL/2) × tCK
PRECHARGE 1 tCK
ACTIVE 1 tCK
READ with auto READ or READ with auto precharge (BL/2) × tCK
precharge WRITE or WRITE with auto precharge [CLRU + (BL/2)] × tCK
PRECHARGE 1 tCK
ACTIVE 1 tCK
4. AUTO REFRESH and LMR commands may only be issued when all banks are idle.
5. A BURST TERMINATE command cannot be issued to another bank; it applies to the bank
represented by the current state only.
6. All states and sequences not shown are illegal or reserved.
7. READs or WRITEs listed in the “Command/Action” column include READs or WRITEs with
auto precharge enabled and READs or WRITEs with auto precharge disabled.
8. Requires appropriate DM masking.
9. A WRITE command may be applied after the completion of the READ burst; otherwise, a
BURST TERMINATE must be used to end the READ burst prior to asserting a WRITE com-
mand.

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Commands

Table 31: Truth Table 5 – CKE

Notes 1–6 apply to the entire table; Notes appear below

CKEn-1 CKEn Current State Commandn Actionn Notes

L L Power-down X Maintain power-down
Self refresh X Maintain self refresh
L H Power-down DESELECT or NOP Exit power-down
Self refresh DESELECT or NOP Exit self refresh 7
H L All banks idle DESELECT or NOP Precharge power-down entry
Bank(s) active DESELECT or NOP Active power-down entry
All banks idle AUTO REFRESH Self refresh entry
H H See Table 26 on page 42
Notes: 1. CKEn is the logic state of CKE at clock edge n; CKEn-1 was the state of CKE at the previous
clock edge.
2. Current state is the state of the DDR SDRAM immediately prior to clock edge n.
3. COMMANDn is the command registered at clock edge n, and ACTIONn is a result of COM-
MANDn.
4. All states and sequences not shown are illegal or reserved.
5. CKE must not drop LOW during a column access. For a READ, this means CKE must stay
HIGH until after the read postamble time (tRPST); for a WRITE, CKE must stay HIGH until the
write recovery time (tWR) has been met.
6. Once initialized, including during self refresh mode, VREF must be powered within the spec-
ified range.
7. Upon exit of the self refresh mode, the DLL is automatically enabled. A minimum of 200
clock cycles is needed before applying a READ command for the DLL to lock. DESELECT or
NOP commands should be issued on any clock edges occurring during the tXSNR period.

DESELECT
The DESELECT function (CS# HIGH) prevents new commands from being executed by
the DDR SDRAM. The DDR SDRAM is effectively deselected. Operations already in
progress are not affected.

NO OPERATION (NOP)
The NO OPERATION (NOP) command is used to instruct the selected DDR SDRAM to
perform a NOP (CS# is LOW with RAS#, CAS#, and WE# are HIGH). This prevents
unwanted commands from being registered during idle or wait states. Operations
already in progress are not affected.

LOAD MODE REGISTER (LMR)

The mode registers are loaded via inputs A[n:0] (see "REGISTER DEFINITION" on page
54). The LMR command can only be issued when all banks are idle, and a subsequent
executable command cannot be issued until tMRD is met.

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Commands

ACTIVE (ACT)
The ACTIVE command is used to open (or activate) a row in a particular bank for a
subsequent access, like a read or a write, as shown in Figure 16. The value on the BA0,
BA1 inputs selects the bank, and the address provided on inputs A[n:0] selects the row.

Figure 16: Activating a Specific Row in a Specific Bank

CK#
CK

CKE HIGH

CS#

RAS#

CAS#

WE#

Address Row

BA0, BA1 Bank

Don’t Care

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Commands

READ
The READ command is used to initiate a burst read access to an active row, as shown in
Figure 17 on page 48. The value on the BA[1:0] inputs selects the bank, and the address
provided on inputs A[i:0] (where Ai is the most significant column address bit for a given
density and configuration, see Table 2 on page 2) selects the starting column location.

Figure 17: READ Command

CK#

CK

CKE HIGH

CS#

RAS#

CAS#

WE#

Address Col

EN AP
A10
DIS AP

BA0, BA1 Bank

Don’t Care

Note: EN AP = enable auto precharge; DIS AP = disable auto precharge.

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Commands

WRITE
The WRITE command is used to initiate a burst write access to an active row as shown in
Figure 18. The value on the BA[1:0] inputs selects the bank, and the address provided on
inputs A[i:0] (where Ai is the most significant column address bit for a given density and
configuration, see Table 2 on page 2) selects the starting column location.

Figure 18: WRITE Command

CK#
CK

CKE HIGH

CS#

RAS#

CAS#

WE#

Address Col

EN AP
A10
DIS AP

BA0, BA1 Bank

Don’t Care

Note: EN AP = enable auto precharge; and DIS AP = disable auto precharge.

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Commands

PRECHARGE (PRE)
The PRECHARGE command is used to deactivate the open row in a particular bank or
the open row in all banks as shown in Figure 19. The value on the BA[1:0] inputs selects
the bank, and the A10 input selects whether a single bank is precharged or whether all
banks are precharged.

Figure 19: PRECHARGE Command

CK#

CK

CKE HIGH

CS#

RAS#

CAS#

WE#

Address

All banks
A10
One bank

BA0, BA1 Bank1

Don’t Care

Notes: 1. If A10 is HIGH, bank address becomes “Don’t Care.”

BURST TERMINATE (BST)

The BURST TERMINATE command is used to truncate READ bursts (with auto
precharge disabled). The most recently registered READ command prior to the BURST
TERMINATE command will be truncated, as shown in “Operations” on page 51. The
open page from which the READ burst was terminated remains open.

AUTO REFRESH (AR)

AUTO REFRESH is used during normal operation of the DDR SDRAM and is analogous
to CAS#-before-RAS# (CBR) refresh in FPM/EDO DRAMs. This command is nonpersis-
tent, so it must be issued each time a refresh is required. All banks must be idle before an
AUTO REFRESH command is issued.

SELF REFRESH
The SELF REFRESH command can be used to retain data in the DDR SDRAM, even if the
rest of the system is powered down. The SELF REFRESH command is initiated like an
AUTO REFRESH command except CKE is disabled (LOW).
Self refresh is not supported on automotive temperature (AAT) devices.

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Operations

Operations
INITIALIZATION
Prior to normal operation, DDR SDRAMs must be powered up and initialized in a
predefined manner. Operational procedures, other than those specified, may result in
undefined operation.
To ensure device operation, the DRAM must be initialized as described in the following
steps:
1. Simultaneously apply power to VDD and VDDQ.
2. Apply VREF and then VTT power. VTT must be applied after VDDQ to avoid device latch-
up, which may cause permanent damage to the device. Except for CKE, inputs are not
recognized as valid until after VREF is applied.
3. Assert and hold CKE at a LVCMOS logic LOW. Maintaining an LVCMOS LOW level on
CKE during power-up is required to ensure that the DQ and DQS outputs will be in
the High-Z state, where they will remain until driven in normal operation (by a read
access).
4. Provide stable clock signals.
5. Wait at least 200µs.
6. Bring CKE HIGH, and provide at least one NOP or DESELECT command. At this
point, the CKE input changes from a LVCMOS input to a SSTL_2 input only and will
remain a SSTL_2 input unless a power cycle occurs.
7. Perform a PRECHARGE ALL command.
8. Wait at least tRP time; during this time NOPs or DESELECT commands must be given.
9. Using the LMR command, program the extended mode register (E0 = 0 to enable the
DLL and E1 = 0 for normal drive; or E1 = 1 for reduced drive and E[n:2] must be set to
0 [where n = most significant bit]).
10. Wait at least tMRD time; only NOPs or DESELECT commands are allowed.
11. Using the LMR command, program the mode register to set operating parameters
and to reset the DLL. At least 200 clock cycles are required between a DLL reset and
any READ command.
12. Wait at least tMRD time; only NOPs or DESELECT commands are allowed.
13. Issue a PRECHARGE ALL command.
14. Wait at least tRP time; only NOPs or DESELECT commands are allowed.
15. Issue an AUTO REFRESH command. This may be moved prior to step 13.
16. Wait at least tRFC time; only NOPs or DESELECT commands are allowed.
17. Issue an AUTO REFRESH command. This may be moved prior to step 13.
18. Wait at least tRFC time; only NOPs or DESELECT commands are allowed.
19. Although not required by the Micron device, JEDEC requires an LMR command to
clear the DLL bit (set M8 = 0). If an LMR command is issued, the same operating
parameters should be utilized as in step 11.
20. Wait at least tMRD time; only NOPs or DESELECT commands are supported.
21. At this point the DRAM is ready for any valid command. At least 200 clock cycles with
CKE HIGH are required between step 11 (DLL RESET) and any READ command.

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Operations

Figure 20: INITIALIZATION Flow Diagram

Step

1 VDD and VDDQ ramp

2 Apply VREF and VTT

3 CKE must be LVCMOS LOW

4 Apply stable CLOCKs

5 Wait at least 200µs

6 Bring CKE HIGH with a NOP command

7 PRECHARGE ALL

8 Assert NOP or DESELECT for tRP time

9 Configure extended mode register

10 Assert NOP or DESELECT for tMRD time

11 Configure load mode register and reset DLL

12 Assert NOP or DESELECT for tMRD time

13 PRECHARGE ALL

14 Assert NOP or DESELECT for tRP time

15 Issue AUTO REFRESH command

16 Assert NOP or DESELECT commands for tRFC

17 Issue AUTO REFRESH command

18 Assert NOP or DESELECT for tRFC time

19 Optional LMR command to clear DLL bit

20 Assert NOP or DESELECT for tMRD time

21 DRAM is ready for any valid command

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Operations

Figure 21: INITIALIZATION Timing Diagram

((
))
VDD
((
))
VDDQ tVTD1
1 ((
VTT ))

VREF ((
))
T0 T1 Ta0 Tb0 Tc0 Td0 Te0 Tf0
CK# (( (( (( (( (( (( ((
)) )) )) )) )) )) ))
CK (( (( (( (( (( (( ((
)) tCH tCL )) )) )) )) )) ))
tIS tIH
LVCMOS (( (( (( (( (( ((
)) )) )) )) )) ))
CKE LOW level ( ( (( (( (( (( (( ((
)) )) )) )) )) )) ))
tIS tIH
(( (( (( (( (( (( ((
)) )) )) )) )) )) ))
Command (( NOP PRE
((
LMR
((
LMR
((
PRE
((
AR
((
AR
(( ACT2
)) )) )) )) )) )) ))
tCK
(( (( (( (( (( (( ((
DM )) )) )) )) )) )) ))
(( (( (( (( (( (( ((
)) )) )) )) )) )) ))
tIS tIH
(( (( (( (( (( (( ((
Address )) )) )) )) )) )) ))
(( Code Code3 RA
(( (( (( (( (( ((
)) )) )) )) )) )) ))
tIS tIH
(( All banks ( ( (( ( ( All banks (( (( ((
A10 )) )) Code )) Code )) )) )) )) RA
(( (( (( (( (( (( ((
)) tIS tIH )) )) )) tIS tIH )) )) ))
tIS tIH
(( (( (( (( (( (( ((
BA[1:0] )) )) BA0 = 1 )) BA0 = 0 )) )) )) )) BA
(( (( BA1 = 0 (( BA1 = 0 (( (( (( ((
)) )) )) )) )) )) ))

DQS (( High-Z (( (( (( (( (( ((
)) )) )) )) )) )) ))

DQ (( High-Z (( (( (( (( (( ((
)) )) )) )) )) )) ))
T = 200µs
tRP tMRD tMRD tRP tRFC tRFC
Power-up: VDD and CK stable Load extended
mode register 200 cycles of CK4
Load mode
register5
Indicates break in Don’t Care
time scale

Notes: 1. VTT is not applied directly to the device; however, tVTD  0 to avoid device latch-up. VDDQ,
VTT, and VREF  VDD + 0.3V. Alternatively, VTT may be 1.35V maximum during power-up,
even if VDD/VDDQ are 0V, provided a minimum of 42of series resistance is used between
the VTT supply and the input pin. Once initialized, VREF must always be powered within the
specified range.
2. Although not required by the Micron device, JEDEC specifies issuing another LMR command
(A8 = 0) prior to activating any bank. If another LMR command is issued, the same, previ-
ously issued operating parameters must be used.
3. The two AUTO REFRESH commands at Td0 and Te0 may be applied following the LMR com-
mand at Ta0.
4. tMRD is required before any command can be applied (during MRD time only NOPs or
DESELECTs are allowed), and 200 cycles of CK are required before a READ command can be
issued.
5. While programming the operating parameters, reset the DLL with A8 = 1.

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Operations

REGISTER DEFINITION
Mode Register
The mode register is used to define the specific DDR SDRAM mode of operation. This
definition includes the selection of a burst length, a burst type, a CAS latency, and an
operating mode, as shown in Figure 22. The mode register is programmed via the LMR
command (with BA0 = 0 and BA1 = 0) and will retain the stored information until it is
programmed again or until the device loses power (except for bit A8, which is self-
clearing).
Reprogramming the mode register will not alter the contents of the memory, provided it
is performed correctly. The mode register must be loaded (reloaded) when all banks are
idle and no bursts are in progress, and the controller must wait the specified time before
initiating the subsequent operation. Violating either of these requirements will result in
unspecified operation.
Mode register bits A[n:7] specify the operating mode, A[6:4] specify the CAS latency, A3
specifies the type of burst (sequential or interleaved), and A[2:0] specify the burst length.

Figure 22: Mode Register Definition

BA1 BA0 An . . . A9 A8 A7 A6 A5 A4 A3 A2 A1 A0 Address bus

n + 2 n + 1 n1 . . . 9 8 7 6 5 4 3 2 1 0 Mode register
0 0 Operating mode CAS Latency BT Burst length (Mx)

M2 M1 M0 Burst Length
Mn + 2 Mn + 1 Mode Register Definition
0 0 0 Reserved
0 0 Base mode register
0 0 1 2
0 1 Extended mode register M3 Burst Type
0 1 0 4
1 0 Reserved 0 Sequential
0 1 1 8
1 1 Reserved 1 Interleaved
1 0 0 Reserved
1 0 1 Reserved
1 1 0 Reserved
Mn . . . M9 M8 M7 M6–M0 Operating Mode
1 1 1 Reserved
0 0 0 0 0 Valid Normal operation
0 0 0 1 0 Valid Normal operation/reset DLL
– – – – – – All other states reserved
M6 M5 M4 CAS Latency
0 0 0 Reserved
0 0 1 Reserved
0 1 0 2
0 1 1 3 (-5B only)
1 0 0 Reserved
1 0 1 Reserved
1 1 0 2.5
1 1 1 Reserved

Notes: 1. n is the most significant row address bit from Table 2 on page 2.

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Operations

Burst Length (BL)

Read and write accesses to the DDR SDRAM are burst oriented, with the burst length
being programmable for both READ and WRITE bursts, as shown in Figure 22 on
page 54. The burst length determines the maximum number of column locations that
can be accessed for a given READ or WRITE command. BL = 2, BL = 4, or BL = 8 locations
are available for both the sequential and the interleaved burst types. Reserved states
should not be used, as unknown operation or incompatibility with future versions may
result.
When a READ or WRITE command is issued, a block of columns equal to the burst
length is effectively selected. All accesses for that burst take place within this block—
meaning that the burst will wrap within the block if a boundary is reached. The block is
uniquely selected by A[i:1] when BL = 2, by A[i:2] when BL = 4, and by A[i:3] when BL = 8
(where Ai is the most significant column address bit for a given configuration). The
remaining (least significant) address bit(s) is (are) used to select the starting location
within the block. For example: for BL = 8, A[i:3] select the eight-data-element block;
A[2:0] select the first access within the block.

Burst Type
Accesses within a given burst may be programmed to be either sequential or interleaved;
this is referred to as the burst type and is selected via bit M3.
The ordering of accesses within a burst is determined by the burst length, the burst type,
and the starting column address, as shown in Table 32.

Table 32: Burst Definition

Order of Accesses Within a Burst

Burst Length Starting Column Address Type = Sequential Type = Interleaved
2 – – A0 – –
– – 0 0-1 0-1
– – 1 1-0 1-0
4 – A1 A0 – –
– 0 0 0-1-2-3 0-1-2-3
– 0 1 1-2-3-0 1-0-3-2
– 1 0 2-3-0-1 2-3-0-1
– 1 1 3-0-1-2 3-2-1-0
8 A2 A1 A0 – –
0 0 0 0-1-2-3-4-5-6-7 0-1-2-3-4-5-6-7
0 0 1 1-2-3-4-5-6-7-0 1-0-3-2-5-4-7-6
0 1 0 2-3-4-5-6-7-0-1 2-3-0-1-6-7-4-5
0 1 1 3-4-5-6-7-0-1-2 3-2-1-0-7-6-5-4
1 0 0 4-5-6-7-0-1-2-3 4-5-6-7-0-1-2-3
1 0 1 5-6-7-0-1-2-3-4 5-4-7-6-1-0-3-2
1 1 0 6-7-0-1-2-3-4-5 6-7-4-5-2-3-0-1
1 1 1 7-0-1-2-3-4-5-6 7-6-5-4-3-2-1-0

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Operations

CAS Latency (CL)

The CL is the delay, in clock cycles, between the registration of a READ command and
the availability of the first bit of output data. The latency can be set to 2, 2.5, or 3 (-5B
only) clocks, as shown in Figure 23. Reserved states should not be used, as unknown
operation or incompatibility with future versions may result.
If a READ command is registered at clock edge n, and the latency is m clocks, the data
will be available nominally coincident with clock edge n + m. Table 33 on page 57 indi-
cates the operating frequencies at which each CL setting can be used.

Figure 23: CAS Latency

T0 T1 T2 T2n T3 T3n
CK#

CK

Command READ NOP NOP NOP

CL = 2

DQS

DQ

T0 T1 T2 T2n T3 T3n
CK#
CK

Command READ NOP NOP NOP

CL = 2.5

DQS

DQ

T0 T1 T2 T3 T3n
CK#

CK

Command READ NOP NOP NOP

CL = 3

DQS

DQ

Transitioning Data Don’t Care

Note: BL = 4 in the cases shown; shown with nominal tAC, tDQSCK, and tDQSQ.

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Operations

Table 33: CAS Latency

Allowable Operating Clock Frequency (MHz)

Speed CL = 2 CL = 2.5 CL = 3
-5B 75  f  133 75  f  167 133  f  200
-6/-6T 75  f  133 75  f  167 –
-75E 75  f  133 75  f  133 –
-75Z 75  f  133 75  f  133 –
-75 75  f  100 75  f  133 –

Operating Mode
The normal operating mode is selected by issuing an LMR command with bits A[n:7]
each set to zero and bits A[6:0] set to the desired values. A DLL reset is initiated by
issuing an LMR command with bits A7 and A[n:9] each set to zero, bit A8 set to one, and
bits A[6:0] set to the desired values. Although not required by the Micron device, JEDEC
specifications recommend that an LMR command resetting the DLL should always be
followed by an LMR command selecting normal operating mode.
All other combinations of values for A[n:7] are reserved for future use and/or test modes.
Test modes and reserved states should not be used, as unknown operation or incompat-
ibility with future versions may result.

Extended Mode Register

The extended mode register controls functions beyond those controlled by the mode
register; these additional functions are DLL enable/disable and output drive strength.
These functions are controlled via the bits shown in Figure 24 on page 58. The extended
mode register is programmed via the LMR command to the mode register (with BA0 = 1
and BA1 = 0) and will retain the stored information until it is programmed again or until
the device loses power. The enabling of the DLL should always be followed by an LMR
command to the mode register (BA0/BA1 = 0) to reset the DLL. The extended mode
register must be loaded when all banks are idle and no bursts are in progress, and the
controller must wait the specified time before initiating any subsequent operation.
Violating either requirement could result in an unspecified operation.

Output Drive Strength

The normal drive strength for all outputs is specified to be SSTL_2, Class II. The Design
Revision F and K devices support a programmable option for reduced drive. This option
is intended for the support of the lighter load and/or point-to-point environments. The
selection of the reduced drive strength will alter the DQ and DQS pins from SSTL_2,
Class II drive strength to a reduced drive strength, which is approximately 54% of the
SSTL_2, Class II drive strength.

DLL Enable/Disable
When the part is running without the DLL enabled, device functionality may be altered.
The DLL must be enabled for normal operation. DLL enable is required during power-
up initialization and upon returning to normal operation after having disabled the DLL
for the purpose of debug or evaluation (when the device exits self refresh mode, the DLL
is enabled automatically). Anytime the DLL is enabled, 200 clock cycles with CKE HIGH
must occur before a READ command can be issued.

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Operations

Figure 24: Extended Mode Register Definition

BA1 BA0 An . . . A9 A8 A7 A6 A5 A4 A3 A2 A1 A0 Address bus

n + 2 n + 1 n1 . . . 9 8 7 6 5 4 3 2 1 0 Extended mode
0 1 Operating Mode DS DLL register (Ex)

E0 DLL
0 Enable
Mn + 2 Mn + 1 Mode Register Definition
1 Disable
0 0 Base mode register
0 1 Extended mode register E1 Drive Strength
1 0 Reserved 0 Normal
1 1 Reserved 1 Reduced

2
En . . . E9 E8 E7 E6 E5 E4 E3 E2 E1, E0 Operating Mode
0 0 0 0 0 0 0 0 0 0 Valid Reserved
– – – – – – – – – – – Reserved

Notes: 1. n is the most significant row address bit from Table 2 on page 2.
2. The QFC# option is not supported.

ACTIVE
After a row is opened with an ACTIVE command, a READ or WRITE command may be
issued to that row, subject to the tRCD specification. tRCD (MIN) should be divided by
the clock period and rounded up to the next whole number to determine the earliest
clock edge after the ACTIVE command on which a READ or WRITE command can be
entered. For example, a tRCD specification of 20ns with a 133 MHz clock (7.5ns period)
results in 2.7 clocks rounded to 3. This is reflected in Figure 25 on page 59, which covers
any case where 2 < tRCD (MIN)/tCK  3 (Figure 25 also shows the same case for tRRD; the
same procedure is used to convert other specification limits from time units to clock
cycles).
A row remains active (or open) for accesses until a PRECHARGE command is issued to
that bank. A PRECHARGE command must be issued before opening a different row in
the same bank.
A subsequent ACTIVE command to a different row in the same bank can only be issued
after the previous active row has been closed (precharged). The minimum time interval
between successive ACTIVE commands to the same bank is defined by tRC.
A subsequent ACTIVE command to another bank can be issued while the first bank is
being accessed, which results in a reduction of total row-access overhead. The minimum
time interval between successive ACTIVE commands to different banks is defined by
t
RRD.

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Operations

Figure 25: Example: Meeting tRCD (tRRD) MIN When 2 < tRCD (tRRD) MIN/tCK 3

T0 T1 T2 T3 T4 T5 T6 T7
CK#
CK

Command ACT NOP NOP ACT NOP NOP RD/WR NOP

Address Row Row Col

BA[1:0] Bank x Bank y Bank y

tRRD tRCD

Don’t Care

READ
During the READ command, the value on input A10 determines whether or not auto
precharge is used. If auto precharge is selected, the row being accessed will be
precharged at the end of the READ burst; if auto precharge is not selected, the row will
remain open for subsequent accesses.
Note: For the READ commands used in the following illustrations, auto precharge is dis-
abled.
During READ bursts, the valid data-out element from the starting column address will
be available following the CL after the READ command. Each subsequent data-out
element will be valid nominally at the next positive or negative clock edge (that is, at the
next crossing of CK and CK#). Figure 26 on page 61 shows the general timing for each
possible CL setting. DQS is driven by the DDR SDRAM along with output data. The
initial LOW state on DQS is known as the read preamble; the LOW state coincident with
the last data-out element is known as the read postamble.
Upon completion of a burst, assuming no other commands have been initiated, the DQ
will go High-Z. Detailed explanations of tDQSQ (valid data-out skew), tQH (data-out
window hold), and the valid data window are depicted in Figure 34 on page 69 and
Figure 35 on page 70. Detailed explanations of tDQSCK (DQS transition skew to CK) and
t
AC (data-out transition skew to CK) are depicted in Figure 36 on page 71.
Data from any READ burst may be concatenated or truncated with data from a subse-
quent READ command. In either case, a continuous flow of data can be maintained. The
first data element from the new burst follows either the last element of a completed
burst or the last desired data element of a longer burst which is being truncated. The
new READ command should be issued x cycles after the first READ command, where x
equals the number of desired data element pairs (pairs are required by the 2n-prefetch
architecture). This is shown in Figure 27 on page 62. A READ command can be initiated
on any clock cycle following a previous READ command. Nonconsecutive read data is
illustrated in Figure 28 on page 63. Full-speed random read accesses within a page (or
pages) can be performed, as shown in Figure 29 on page 64.

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Operations

Data from any READ burst may be truncated with a BURST TERMINATE command, as
shown in Figure 30 on page 65. The BURST TERMINATE latency is equal to the CL, that
is, the BURST TERMINATE command should be issued x cycles after the READ
command where x equals the number of desired data element pairs (pairs are required
by the 2n-prefetch architecture).
Data from any READ burst must be completed or truncated before a subsequent WRITE
command can be issued. If truncation is necessary, the BURST TERMINATE command
must be used, as shown in Figure 31 on page 66. The tDQSS (NOM) case is shown; the
t
DQSS (MAX) case has a longer bus idle time. (tDQSS [MIN] and tDQSS [MAX] are
defined in the section on WRITEs.) A READ burst may be followed by, or truncated with,
a PRECHARGE command to the same bank provided that auto precharge was not acti-
vated.
The PRECHARGE command should be issued x cycles after the READ command, where
x equals the number of desired data element pairs (pairs are required by the 2n-prefetch
architecture). This is shown in Figure 32 on page 67. Following the PRECHARGE
command, a subsequent command to the same bank cannot be issued until both tRAS
and tRP have been met. Part of the row precharge time is hidden during the access of the
last data elements.

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Operations

Figure 26: READ Burst

T0 T1 T2 T2n T3 T3n T4 T5
CK#
CK

Command READ NOP NOP NOP NOP NOP

Address Bank a,
Col n
CL = 2

DQS

DQ DO
n

T0 T1 T2 T2n T3 T3n T4 T5
CK#
CK

Command READ NOP NOP NOP NOP NOP

Bank a,
Address Col n
CL = 2.5

DQS

DQ DO
n

T0 T1 T2 T3 T3n T4 T4n T5
CK#
CK

Command READ NOP NOP NOP NOP NOP

Bank a,
Address Col n
CL = 3

DQS

DQ DO
n

Transitioning Data Don’t Care

Notes: 1. DO n = data-out from column n.

2. BL = 4.
3. Three subsequent elements of data-out appear in the programmed order following DO n.
4. Shown with nominal tAC, tDQSCK, and tDQSQ.

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Operations

Figure 27: Consecutive READ Bursts

T0 T1 T2 T2n T3 T3n T4 T4n T5 T5n

CK#
CK

Command READ NOP READ NOP NOP NOP

Bank, Bank,
Address Col n Col b
CL = 2

DQS

DO DO
DQ n b

T0 T1 T2 T2n T3 T3n T4 T4n T5 T5n

CK#
CK

Command READ NOP READ NOP NOP NOP

Bank, Bank,
Address Col n Col b
CL = 2.5

DQS

DQ DO DO
n b

T0 T1 T2 T3 T3n T4 T4n T5 T5n

CK#
CK

Command READ NOP READ NOP NOP NOP

Address Bank, Bank,

Col n Col b
CL = 3

DQS

DQ DO DO
n b

Transitioning Data Don’t Care

Notes: 1. DO n (or b) = data-out from column n (or column b).

2. BL = 4 or BL = 8 (if BL = 4, the bursts are concatenated; if BL = 8, the second burst interrupts
the first).
3. Three subsequent elements of data-out appear in the programmed order following DO n.
4. Three (or seven) subsequent elements of data-out appear in the programmed order follow-
ing DO b.
5. Shown with nominal tAC, tDQSCK, and tDQSQ.
6. Example applies only when READ commands are issued to same device.

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Operations

Figure 28: Nonconsecutive READ Bursts

T0 T1 T2 T2n T3 T3n T4 T5 T5n T6

CK#
CK
Command READ NOP NOP READ NOP NOP NOP

Address Bank, Bank,

Col n Col b
CL = 2

DQS

DQ DO DO
n b

T0 T1 T2 T2n T3 T3n T4 T5 T5n T6

CK#
CK
Command READ NOP NOP READ NOP NOP NOP

Bank, Bank,
Address Col n Col b
CL = 2.5

DQS

DQ DO DO
n b

T0 T1 T2 T3 T3n T4 T4n T5 T6
CK#
CK
Command READ NOP NOP READ NOP NOP NOP

Address Bank, Bank,

Col n Col b
CL = 3

DQS

DQ DO DO
n b

Transitioning Data Don’t Care

Notes: 1. DO n (or b) = data-out from column n (or column b).

2. BL = 4 or BL = 8 (if BL = 4, the bursts are concatenated; if BL = 8, the second burst interrupts
the first).
3. Three subsequent elements of data-out appear in the programmed order following DO n.
4. Three (or seven) subsequent elements of data-out appear in the programmed order follow-
ing DO b.
5. Shown with nominal tAC, tDQSCK, and tDQSQ.

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Operations

Figure 29: Random READ Accesses

T0 T1 T2 T2n T3 T3n T4 T4n T5 T5n

CK#
CK

Command READ READ READ READ NOP NOP

Address Bank, Bank, Bank, Bank,

Col n Col x Col b Col g
CL = 2
DQS

DQ DO DO DO DO DO DO DO
n n' x x' b b' g

T0 T1 T2 T2n T3 T3n T4 T4n T5 T5n

CK#
CK

Command READ READ READ READ NOP NOP

Bank, Bank, Bank, Bank,

Address Col n Col x Col b Col g
CL = 2.5

DQS

DQ DO DO DO DO DO DO
n n' x x' b b'

T0 T1 T2 T3 T3n T4 T4n T5 T5n

CK#
CK

Command READ READ READ READ NOP NOP

Address Bank, Bank, Bank, Bank,

Col n Col x Col b Col g
CL = 3

DQS

DQ DO DO DO DO DO DO
n n' x x' b b'

Transitioning Data Don’t Care

Notes: 1. DO n (or x or b or g) = data-out from column n (or column x or column b or column g).
2. BL = 2, BL = 4, or BL = 8 (if BL = 4 or BL = 8, the following burst interrupts the previous).
3. n', x', b', or g' indicate the next data-out following DO n, DO x, DO b, or DO g, respectively.
4. READs are to an active row in any bank.
5. Shown with nominal tAC, tDQSCK, and tDQSQ.

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Operations

Figure 30: Terminating a READ Burst

T0 T1 T2 T2n T3 T4 T5
CK#
CK
Command READ BST1 NOP NOP NOP NOP

Address Bank a,
Col n
CL = 2

DQS

DO
DQ n

T0 T1 T2 T2n T3 T4 T5
CK#
CK

Command READ BST1 NOP NOP NOP NOP

Bank a,
Address Col n
CL = 2.5

DQS

DO
DQ n

T0 T1 T2 T3 T3n T4 T5
CK#
CK

Command READ BST1 NOP NOP NOP NOP

Bank a,
Address Col n
CL = 3

DQS

DO
DQ n

Transitioning Data Don’t Care

Notes: 1. Page remains open.

2. DO n = data-out from column n.
3. BL = 4.
4. Subsequent element of data-out appears in the programmed order following DO n.
5. Shown with nominal tAC, tDQSCK, and tDQSQ.

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Operations

Figure 31: READ-to-WRITE

T0 T1 T2 T2n T3 T4 T4n T5 T5n

CK#
CK

Command READ 1 NOP WRITE NOP NOP

BST

Address Bank, Bank,

Col n Col b
tDQSS
CL = 2 (NOM)

DQS

DQ DO DI
n b

DM

T0 T1 T2 T2n T3 T3n T4 T5 T5n

CK#
CK

Command READ 1 NOP NOP WRITE NOP

BST

Address Bank, Bank,

Col n Col b
tDQSS
CL = 2.5 (NOM)

DQS

DQ DO DI
n b

DM

T0 T1 T2 T3 T3n T4 T5 T5n
CK#
CK

Command READ BST1 NOP NOP WRITE NOP

Address Bank a,
Col n
tDQSS
CL = 3 (NOM)

DQS

DQ DO DI
n b

DM

Transitioning Data Don’t Care

Notes: 1. Page remains open.

2. DO n = data-out from column n; DI b = data-in from column b.
3. BL = 4 (applies for bursts of 8 as well; if BL = 2, the BURST command shown can be NOP).
4. One subsequent element of data-out appears in the programmed order following DO n.
5. Data-in elements are applied following DI b in the programmed order.
6. Shown with nominal tAC, tDQSCK, and tDQSQ.

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Operations

Figure 32: READ-to-PRECHARGE

T0 T1 T2 T2n T3 T3n T4 T5
CK#
CK

Command READ NOP PRE NOP NOP ACT

Bank a, Bank a, Bank a,

Address Col n (a or all) Row
CL = 2 tRP

DQS

DQ DO
n

T0 T1 T2 T2n T3 T3n T4 T5
CK#
CK

Command READ NOP PRE NOP NOP ACT

Address Bank a, Bank a, Bank a,

Col n (a or all) Row
tRP
CL = 2.5

DQS

DQ DO
n

T0 T1 T2 T3 T3n T4 T4n T5
CK#
CK

Command READ NOP PRE NOP NOP ACT

Bank a, Bank a, Bank a,

Address Col n (a or all) Row
tRP
CL = 3

DQS

DQ DO
n

Transitioning Data Don’t Care

Notes: 1. Provided tRAS (MIN) is met, a READ command with auto precharge enabled would cause a
precharge to be performed at x number of clock cycles after the READ command, where
x = BL/2.
2. DO n = data-out from column n.
3. BL = 4 or an interrupted burst of 8.
4. Three subsequent elements of data-out appear in the programmed order following DO n.
5. Shown with nominal tAC, tDQSCK, and tDQSQ.
6. READ-to-PRECHARGE equals two clocks, which allows two data pairs of data-out; it is also
assumed that tRAS (MIN) is met.
7. An ACTIVE command to the same bank is only allowed if tRC (MIN) is met.

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Operations

Figure 33: Bank READ – Without Auto Precharge

T0 T1 T2 T3 T4 T5 T5n T6 T6n T7 T8
CK#
CK
tIS tIH tCK tCH tCL

CKE
tIS tIH

Command NOP1 ACT NOP1 READ2 NOP1 PRE3 NOP1 NOP1 ACT

tIS tIH

Address Row Col n Row

tIS tIH
All banks
4
A10 Row Row
One bank
tIS tIH

BA[1:0] Bank x Bank x 5 Bank x

Bank x

tRCD CL = 2

tRAS3 tRP

tRC

DM

Case 1: tAC (MIN) and tDQSCK (MIN) tRPRE tDQSCK (MIN) tRPST

DQS
tLZ (MIN)

DO
DQ n

tLZ (MIN) tAC (MIN)

Case 2: tAC (MAX) and tDQSCK (MAX) tRPRE tDQSCK (MAX) tRPST

DQS

DO
DQ n

tAC (MAX) tHZ (MAX)

Transitioning Data Don’t Care

Notes: 1. NOP commands are shown for ease of illustration; other commands may be valid at these
times.
2. BL = 4.
3. The PRECHARGE command can only be applied at T5 if tRAS (MIN) is met.
4. Disable auto precharge.
5. “Don’t Care” if A10 is HIGH at T5.
6. DO n (or b) = data-out from column n (or column b); subsequent elements are provided in
the programmed order.
7. Refer to Figure 34 on page 69, Figure 35 on page 70, and Figure 36 on page 71 for detailed
DQS and DQ timing.

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Operations

Figure 34: x8 Data Output Timing – tDQSQ, tQH, and Data Valid Window

T1 T2 T2n T3 T3n T4

CK#

CK

tHP1 tHP1 tHP1 tHP1 tHP1 tHP1

tDQSQ2 tDQSQ2 tDQSQ2 tDQSQ2

3
DQS

DQ (last data valid)

DQ
DQ
DQ
DQ
DQ
DQ
DQ (first data no longer valid)

tQH4 tQH4 tQH4 tQH4

DQ (last data valid) T2 T2n T3 T3n

DQ (first data no longer valid) T2 T2n T3 T3n

5
All DQ and DQS collectively T2 T2n T3 T3n

Earliest signal transition

Latest signal transition

Data Data Data Data

valid valid valid valid
window window window window

tHP
Notes: 1. is the lesser of tCL or tCH clock transition collectively when a bank is active.
2. t
DQSQ is derived at each DQS clock edge, is not cumulative over time, begins with DQS
transition, and ends with the last valid DQ transition.
3. DQ transitioning after DQS transition define the tDQSQ window. DQS transitions at T2 and
T2n are an “early DQS”; at T3, a “nominal DQS”; and at T3n, a “late DQS”.
4. tQH is derived from tHP: tQH = tHP - tQHS.
5. The data valid window is derived for each DQS transitions and is defined as tQH - tDQSQ.

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 256Mb: x8, x16 Automotive DDR SDRAM
Operations

Figure 35: x16 Data Output Timing – tDQSQ, tQH, and Data Valid Window

T1 T2 T2n T3 T3n T4
CK#
CK
tHP1 tHP1 tHP1 tHP1 tHP1 tHP1

tDQSQ2 tDQSQ2 tDQSQ2 tDQSQ2

LDQS3

4
DQ (last data valid)
4
DQ
4
DQ
4
DQ
4
DQ

Lower byte
4
DQ
4
DQ
4
DQ (first data no longer valid)

tQH5 tQH5 tQH5 tQH5

4
DQ (last data valid) T2 T2n T3 T3n

4
DQ (first data no longer valid) T2 T2n T3 T3n

6
DQ[7:0] and LDQS collectively T2 T2n T3 T3n

Data valid Data valid Data valid Data valid

window window window window
tDQSQ2 tDQSQ2 tDQSQ2 tDQSQ2

3
UDQS

7
DQ (last data valid)
7
DQ
7
DQ
7
DQ
7
DQ

Upper byte
7
DQ
7
DQ
7
DQ (first data no longer valid)

tQH5 tQH5 tQH5 tQH5

7
DQ (last data valid) T2 T2n T3 T3n

7
DQ (first data no longer valid) T2 T2n T3 T3n

6
DQ[15:8] and UDQS collectively T2 T2n T3 T3n

Data valid Data valid Data valid Data valid

window window window window

tHP
Notes: 1. is the lesser of tCL or tCH clock transition collectively when a bank is active.
2. tDQSQ
is derived at each DQS clock edge, is not cumulative over time, begins with DQS
transition, and ends with the last valid DQ transition.
3. DQ transitioning after DQS transition define the tDQSQ window. LDQS defines the lower
byte, and UDQS defines the upper byte.
4. DQ7, DQ6, DQ5, DQ4, DQ3, DQ2, DQ1, or DQ0.
tQH is derived from tHP: tQH = tHP - tQHS.
5.
6. The data valid window is derived for each DQS transition and is tQH - tDQSQ.
7. DQ15, DQ14, DQ13, D12, DQ11, DQ10, DQ9, or DQ8.

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Operations

Figure 36: Data Output Timing – tAC and tDQSCK

T01 T1 T2 T2n T3 T3n T4 T4n T5 T5n T6

CK#
CK
t
tDQSCK2 (MAX) tDQSCK2 (MAX) HZ (MAX)
tLZ (MIN) tDQSCK2 (MIN) tDQSCK2 (MIN)

tRPRE tRPST
DQS or LDQS/UDQS3

DQ (last data valid) T2 T2n T3 T3n T4 T4n T5 T5n

DQ (first data valid) T2 T2n T3 T3n T4 T4n T5 T5n

All DQ values collectively4 T2 T2n T3 T3n T4 T4n T5 T5n

tLZ (MIN) tAC5 (MIN) tAC5 (MAX)

tHZ (MAX)

Notes: 1. READ command with CL = 2 issued at T0.

2. tDQSCK is the DQS output window relative to CK and is the “long term” component of the
DQS skew.
3. DQ transitioning after DQS transition define the tDQSQ window.
4. All DQ must transition by tDQSQ after DQS transitions, regardless of tAC.
5. tAC is the DQ output window relative to CK and is the “long term” component of DQ skew.
6. tLZ (MIN) and tAC (MIN) are the first valid signal transitions.
7. tHZ (MAX) and tAC (MAX) are the latest valid signal transitions.

WRITE
During a WRITE command, the value on input A10 determines whether or not auto
precharge is used. If auto precharge is selected, the row being accessed will be
precharged at the end of the WRITE burst (after tWR time); if auto precharge is not
selected, the row will remain open for subsequent accesses.
Input data appearing on the DQ is written to the memory array subject to the DM input
logic level appearing coincident with the data. If a given DM signal is registered LOW, the
corresponding data will be written to memory. If the DM signal is registered HIGH, the
corresponding data inputs will be ignored, and a WRITE will not be executed to that
byte/column location.
Note: For the WRITE commands used in the following illustrations, auto precharge is dis-
abled.
During WRITE bursts, the first valid data-in element will be registered on the first rising
edge of DQS following the WRITE command, and subsequent data elements will be
registered on successive edges of DQS. The LOW state on DQS between the WRITE
command and the first rising edge is known as the write preamble; the LOW state on
DQS following the last data-in element is known as the write postamble.
The time between the WRITE command and the first corresponding rising edge of DQS
(tDQSS) is specified with a relatively wide range (from 75% to 125% of one clock cycle).
All of the WRITE diagrams show the nominal case, and where the two extreme cases
(that is, tDQSS [MIN] and tDQSS [MAX]) might not be intuitive; they have also been
included. Figure 37 on page 73 shows the nominal case and the extremes of tDQSS for BL
= 4. Upon completion of a burst, assuming no other commands have been initiated, the
DQ will remain High-Z and any additional input data will be ignored.

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Operations

Data for any WRITE burst may be concatenated with or truncated with a subsequent
WRITE command. In either case, a continuous flow of input data can be maintained.
The new WRITE command can be issued on any positive edge of clock following the
previous WRITE command. The first data element from the new burst is applied after
either the last element of a completed burst or the last desired data element of a longer
burst which is being truncated. The new WRITE command should be issued x cycles
after the first WRITE command, where x equals the number of desired data element
pairs (pairs are required by the 2n-prefetch architecture).
Figure 38 on page 74 shows concatenated bursts of 4. An example of nonconsecutive
WRITEs is shown in Figure 39 on page 75. Full-speed random write accesses within a
page or pages can be performed as shown in Figure 40 on page 75.
Data for any WRITE burst may be followed by a subsequent READ command. To follow a
WRITE without truncating the WRITE burst, tWTR should be met, as shown in Figure 41
on page 76.
Data for any WRITE burst may be truncated by a subsequent READ command, as shown
in Figure 42 on page 77.
Note that only the data-in pairs that are registered prior to the tWTR period are written
to the internal array, and any subsequent data-in should be masked with DM, as shown
in Figure 43 on page 78.
Data for any WRITE burst may be followed by a subsequent PRECHARGE command. To
follow a WRITE without truncating the WRITE burst, tWR should be met, as shown in
Figure 44 on page 79.
Data for any WRITE burst may be truncated by a subsequent PRECHARGE command, as
shown in Figure 45 on page 80 and Figure 46 on page 81. Only the data-in pairs regis-
tered prior to the tWR period are written to the internal array; any subsequent data-in
should be masked with DM, as shown in Figures 45 and 46. After the PRECHARGE
command, a subsequent command to the same bank cannot be issued until tRP is met.

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Operations

Figure 37: WRITE Burst

T0 T1 T2 T2n T3
CK#

CK

Command WRITE NOP NOP NOP

Address Bank a,
Col b

tDQSS (NOM)
tDQSS
DQS

DI
DQ b

DM

tDQSS (MIN)
tDQSS
DQS

DI
DQ
b

DM

tDQSS (MAX)
tDQSS
DQS

DI
DQ
b

DM

Transitioning Data Don’t Care

Notes: 1. DI b = data-in for column b.

2. Three subsequent elements of data-in are applied in the programmed order following DI b.
3. An uninterrupted burst of 4 is shown.
4. A10 is LOW with the WRITE command (auto precharge is disabled).

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Operations

Figure 38: Consecutive WRITE-to-WRITE

T0 T1 T1n T2 T2n T3 T3n T4 T4n T5

CK#

CK

Command WRITE NOP WRITE NOP NOP NOP

Bank, Bank,
Address
Col b Col n

tDQSS (NOM) tDQSS

DQS

DI DI
DQ
b n

DM

Transitioning Data Don’t Care

Notes: 1. DI b (or n) = data-in from column b (or column n).

2. Three subsequent elements of data-in are applied in the programmed order following DI b.
3. Three subsequent elements of data-in are applied in the programmed order following DI n.
4. An uninterrupted burst of 4 is shown.
5. Each WRITE command may be to any bank.

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Operations

Figure 39: Nonconsecutive WRITE-to-WRITE

T0 T1 T1n T2 T2n T3 T4 T4n T5 T5n

CK#

CK

Command WRITE NOP NOP WRITE NOP NOP

Bank, Bank,
Address
Col b Col n

tDQSS (NOM) tDQSS

DQS

DI DI
DQ b n

DM

Transitioning Data Don’t Care

Notes: 1. DI b (or n) = data-in from column b (or column n).

2. Three subsequent elements of data-in are applied in the programmed order following DI b.
3. Three subsequent elements of data-in are applied in the programmed order following DI n.
4. An uninterrupted burst of 4 is shown.
5. Each WRITE command may be to any bank.

Figure 40: Random WRITE Cycles

T0 T1 T1n T2 T2n T3 T3n T4 T4n T5 T5n

CK#
CK

Command WRITE WRITE WRITE WRITE WRITE NOP

Address Bank, Bank, Bank, Bank, Bank,

Col b Col x Col n Col a Col g

tDQSS (NOM)

DQS

DI DI DI DI DI DI DI DI DI DI
DQ b b' x x' n n' a a' g g'

DM

Transitioning Data Don’t Care

Notes: 1. DI b (or x or n or a or g) = data-in from column b (or column x, or column n, or column a, or

column g).
2. b', x', n', a' or g' indicate the next data-in following DO b, DO x, DO n, DO a, or DO g,
respectively.
3. Programmed BL = 2, BL = 4, or BL = 8 in cases shown.
4. Each WRITE command may be to any bank.

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Operations

Figure 41: WRITE-to-READ – Uninterrupting

T0 T1 T1n T2 T2n T3 T4 T5 T6 T6n

CK#
CK
Command WRITE NOP NOP NOP READ NOP NOP
tWTR

Address Bank a, Bank a,

Col b Col n

tDQSS (NOM) tDQSS CL = 2

DQS

DI DO
DQ b n

DM

tDQSS (MIN) tDQSS CL = 2

DQS

DI DO
DQ b n

DM

tDQSS (MAX) tDQSS CL = 2

DQS

DI DO
DQ b n

DM

Transitioning Data Don’t Care

Notes: 1. DI b = data-in for column b; DO n = data-out for column n.

2. Three subsequent elements of data-in are applied in the programmed order following DI b.
3. An uninterrupted burst of 4 is shown.
tWTR is referenced from the first positive CK edge after the last data-in pair.
4.
5. The READ and WRITE commands are to the same device. However, the READ and WRITE
commands may be to different devices, in which case tWTR is not required, and the READ
command could be applied earlier.
6. A10 is LOW with the WRITE command (auto precharge is disabled).

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Operations

Figure 42: WRITE-to-READ – Interrupting

T0 T1 T1n T2 T2n T3 T3n T4 T5 T5n T6 T6n

CK#
CK
Command WRITE NOP NOP READ NOP NOP NOP
tWTR

Address Bank a, Bank a,

Col b Col n

tDQSS (NOM) tDQSS CL = 2

DQS

DI DO
DQ b n

DM

tDQSS (MIN) tDQSS CL = 2

DQS

DI DO
DQ b n

DM

tDQSS (MAX) tDQSS CL = 2

DQS

DI DO
DQ b n

DM

Transitioning Data Don’t Care

Notes: 1. DI b = data-in for column b; DO n = data-out for column n.

2. An interrupted burst of 4 is shown; two data elements are written.
3. One subsequent element of data-in is applied in the programmed order following DI b.
tWTR is referenced from the first positive CK edge after the last data-in pair.
4.
5. A10 is LOW with the WRITE command (auto precharge is disabled).
6. DQS is required at T2 and T2n (nominal case) to register DM.
7. If the burst of 8 is used, DM and DQS are required at T3 and T3n because the READ com-
mand will not mask these two data elements.

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Operations

Figure 43: WRITE-to-READ – Odd Number of Data, Interrupting

T0 T1 T1n T2 T2n T3 T3n T4 T5 T5n T6 T6n

CK#

CK
Command WRITE NOP NOP READ NOP NOP NOP
tWTR

Address Bank a, Bank a,

Col b Col n

tDQSS (NOM) tDQSS CL = 2

DQS

DI DO
DQ
b n

DM

tDQSS (MIN) tDQSS CL = 2

DQS

DI DO
DQ
b n

DM

tDQSS (MAX) tDQSS CL = 2

DQS

DI DO
DQ
b n

DM

Transitioning Data Don’t Care

Notes: 1. DI b = data-in for column b; DO n = data-out for column n.

2. An interrupted burst of 4 is shown; one data element is written.
t
3. WTR is referenced from the first positive CK edge after the last desired data-in pair (not
the last two data elements).
4. A10 is LOW with the WRITE command (auto precharge is disabled).
5. DQS is required at T1n, T2, and T2n (nominal case) to register DM.
6. If the burst of 8 is used, DM and DQS are required at T3–T3n because the READ command
will not mask these data elements.

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Operations

Figure 44: WRITE-to-PRECHARGE – Uninterrupting

T0 T1 T1n T2 T2n T3 T4 T5 T6
CK#

CK

Command WRITE NOP NOP NOP NOP PRE NOP

tWR tRP

Address Bank a, Bank,

Col b (a or all)

tDQSS (NOM) tDQSS

DQS

DI
DQ b

DM

tDQSS (MIN) tDQSS

DQS

DI
DQ b

DM

tDQSS (MAX) tDQSS

DQS

DI
DQ b

DM

Transitioning Data Don’t Care

Notes: 1. DI b = data-in for column b.

2. Three subsequent elements of data-in are applied in the programmed order following DI b.
3. An uninterrupted burst of 4 is shown.
tWR is referenced from the first positive CK edge after the last data-in pair.
4.
5. The PRECHARGE and WRITE commands are to the same device. However, the PRECHARGE
and WRITE commands may be to different devices, in which case tWR is not required, and
the PRECHARGE command could be applied earlier.
6. A10 is LOW with the WRITE command (auto precharge is disabled).

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Operations

Figure 45: WRITE-to-PRECHARGE – Interrupting

T0 T1 T1n T2 T2n T3 T3n T4 T4n T5 T6

CK#
CK

Command WRITE NOP NOP NOP PRE NOP NOP

tWR tRP

Address Bank a, Bank,

Col b (a or all)

tDQSS (NOM) tDQSS

DQS

DI
DQ b

DM

tDQSS (MIN) tDQSS

DQS

DI
DQ b

DM

tDQSS (MAX) tDQSS

DQS

DI
DQ b

DM

Transitioning Data Don’t Care

Notes: 1. DI b = data-in for column b.

2. Subsequent element of data-in is applied in the programmed order following DI b.
3. An interrupted burst of 8 is shown; two data elements are written.
tWR is referenced from the first positive CK edge after the last data-in pair.
4.
5. A10 is LOW with the WRITE command (auto precharge is disabled).
6. DQS is required at T4 and T4n (nominal case) to register DM.
7. If the burst of 4 is used, DQS and DM are not required at T3, T3n, T4, and T4n.

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Operations

Figure 46: WRITE-to-PRECHARGE – Odd Number of Data, Interrupting

T0 T1 T1n T2 T2n T3 T3n T4 T4n T5 T6

CK#

CK

Command WRITE NOP NOP NOP PRE NOP NOP

tWR tRP

Address Bank a, Bank,

Col b (a or all)

tDQSS (NOM) tDQSS

DQS

DI
DQ b

DM

tDQSS (MIN) tDQSS

DQS

DI
DQ b

DM

tDQSS (MAX) tDQSS

DQS

DI
DQ b

DM

Transitioning Data Don’t Care

Notes: 1. DI b = data-in for column b.

2. An interrupted burst of 8 is shown; one data element is written.
t
3. WR is referenced from the first positive CK edge after the last data-in pair.
4. A10 is LOW with the WRITE command (auto precharge is disabled).
5. DQS is required at T4 and T4n (nominal case) to register DM.
6. If the burst of 4 is used, DQS and DM are not required at T3, T3n, T4, and T4n.

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Operations

Figure 47: Bank WRITE – Without Auto Precharge

T0 T1 T2 T3 T4 T4n T5 T5n T6 T7 T8
CK#
CK
tIS tIH tCK tCH tCL

CKE
tIS tIH

Command NOP1 ACT NOP1 WRITE2 NOP1 NOP1 NOP1 NOP1 PRE

tIS tIH

Address Row Col n

tIS tIH
All banks
A10 Row 3
One bank
tIS tIH

BA0, BA1 Bank x Bank x Bank x4

tRCD tWR

tRAS tRP

tDQSS (NOM)

DQS

tWPRES tWPRE tDQSL tDQSH tWPST

DI
DQ5 b

DM

tDS tDH

Transitioning Data Don’t Care

Notes: 1. NOP commands are shown for ease of illustration; other commands may be valid at these
times.
2. BL = 4.
3. Disable auto precharge.
4. “Don’t Care” if A10 is HIGH at T8.
5. DI b = data-in from column b; subsequent elements are provided in the programmed order.
6. See Figure 49 on page 84 for detailed DQ timing.

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Operations

Figure 48: WRITE – DM Operation

T0 T1 T2 T3 T4 T4n T5 T5n T6 T7 T8
CK#
CK
tIS tIH tCK tCH tCL

CKE
tIS tIH

1 ACT 1 2 1 1 1 1 PRE
Command NOP NOP WRITE NOP NOP NOP NOP

tIS tIH

Address Row Col n

tIS tIH
All banks
A10 Row 3
One bank
tIS tIH

BA0, BA1 Bank x Bank x 4

Bank x

tRCD tWR

tRAS tRP

tDQSS (NOM)

DQS

tWPRES tWPRE tDQSL tDQSH tWPST

5 DI
DQ b

DM

tDS tDH

Transitioning Data Don’t Care

Notes: 1. NOP commands are shown for ease of illustration; other commands may be valid at these
times.
2. BL = 4.
3. Disable auto precharge.
4. “Don’t Care” if A10 is HIGH at T8.
5. DI b = data-in from column b; subsequent elements are provided in the programmed order.
6. See Figure 49 on page 84 for detailed DQ timing.

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Operations

Figure 49: Data Input Timing

1
T0 T1 T1n T2 T2n T3
CK#
CK
tDQSS tDSH2 tDSS3 tDSH2 tDSS3

DQS

tWPRES tWPRE tDQSL tDQSH tWPST

DQ DI
b

DM

tDS tDH

Transitioning Data Don’t Care

Notes: 1. WRITE command issued at T0.

tDSH
2. (MIN) generally occurs during tDQSS (MIN).
3. tDSS (MIN) generally occurs during tDQSS (MAX).

4. For x16, LDQS controls the lower byte and UDQS controls the upper byte.
5. DI b = data-in from column b.

PRECHARGE
The bank(s) will be available for a subsequent row access a specified time (tRP) after the
PRECHARGE command is issued, except in the case of concurrent auto precharge. With
concurrent auto precharge, a READ or WRITE command to a different bank is allowed as
long as it does not interrupt the data transfer in the current bank and does not violate
any other timing parameters. Input A10 determines whether one or all banks are to be
precharged, and in the case where only one bank is to be precharged, inputs BA[1:0]
select the bank. When all banks are to be precharged, BA[1:0] are treated as “Don’t Care.”
Once a bank has been precharged, it is in the idle state and must be activated prior to
any READ or WRITE commands being issued to that bank. A PRECHARGE command
will be treated as a NOP if there is no open row in that bank (idle state), or if the previ-
ously open row is already in the process of precharging.

Auto Precharge
Auto precharge is a feature which performs the same individual-bank precharge func-
tion described above, but without requiring an explicit command. This is accomplished
by using A10 to enable auto precharge in conjunction with a specific READ or WRITE
command. A precharge of the bank/row that is addressed with the READ or WRITE
command is automatically performed upon completion of the READ or WRITE burst.
Auto precharge is either enabled or disabled for each individual READ or WRITE
command. This device supports concurrent auto precharge if the command to the other
bank does not interrupt the data transfer to the current bank.
Auto precharge ensures that the precharge is initiated at the earliest valid stage within a
burst. This “earliest valid stage” is determined as if an explicit PRECHARGE command
was issued at the earliest possible time, without violating tRAS (MIN), as described for
each burst type in “Operations” on page 51. The user must not issue another command
to the same bank until the precharge time (tRP) is completed.

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Operations

Figure 50: Bank READ – with Auto Precharge

T0 T1 T2 T3 T4 T5 T5n T6 T6n T7 T8
CK#
CK
tIS tIH tCK tCH tCL

CKE
tIS tIH

1 ACT 1 2,3 1 1 1 1 ACT

Command NOP NOP READ NOP NOP NOP NOP
tIS tIH

Address Row Col n Row

4
A10 Row tIS tIH Row

IS IH

BA[1:0] Bank x Bank x Bank x

tRCD, tRAP3 CL = 2

tRAS tRP5

tRC

DM

Case 1: tAC (MIN) and tDQSCK (MIN)

tDQSCK (MIN)
tRPRE tRPST

DQS
tLZ (MIN)

6 DO
DQ n

tLZ (MIN) tAC (MIN)

Case 2: tAC (MAX) and tDQSCK (MAX)

tDQSCK (MAX)
tRPRE tRPST

DQS

6 DO
DQ n

tAC (MAX) tHZ (MAX)

Transitioning Data Don’t Care

Notes: 1. NOP commands are shown for ease of illustration; other commands may be valid at these
times.
2. BL = 4.
3. The READ command can only be applied at T3 if tRAP is satisfied at T3.
4. Enable auto precharge.
5. tRP starts only after tRAS has been satisfied.
6. DO n = data-out from column n; subsequent elements are provided in the programmed
order.
7. Refer to Figure 34 on page 69, Figure 35 on page 70, and Figure 36 on page 71 for detailed
DQS and DQ timing.

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Operations

Figure 51: Bank WRITE – with Auto Precharge

T0 T1 T2 T3 T4 T4n T5 T5n T6 T7 T8
CK#
CK
tIS tIH tCK tCH tCL

CKE
tIS tIH

Command 1 1 2 1 1 1 1 1
NOP ACT NOP WRITE NOP NOP NOP NOP NOP

tIS tIH

Address Row Col n

A10 Row
tIS tIH
tIS tIH

BA0, BA1 Bank x Bank x

tRCD tWR

tRAS tRP

tDQSS (NOM)

DQS

tWPRES tWPRE tDQSL tDQSH tWPST

4 DI
DQ b

DM

tDS tDH

Transitioning Data Don’t Care

Notes: 1. NOP commands are shown for ease of illustration; other commands may be valid at these
times.
2. BL = 4.
3. Enable auto precharge.
4. DI n = data-out from column n; subsequent elements are provided in the programmed
order.
5. See Figure 49 on page 84 for detailed DQ timing.

AUTO REFRESH
During auto refresh, the addressing is generated by the internal refresh controller. This
makes the address bits a “Don’t Care” during an AUTO REFRESH command. The DDR
SDRAM requires AUTO REFRESH cycles at an average interval of tREFI (MAX).
To allow for improved efficiency in scheduling and switching between tasks, some flexi-
bility in the absolute refresh interval is provided. A maximum of eight AUTO REFRESH
commands can be posted to any given DDR SDRAM, meaning that the maximum abso-
lute interval between any AUTO REFRESH command and the next AUTO REFRESH
command is 9 × tREFI(= tREFC). JEDEC specifications only support 8 × tREFI; Micron
specifications exceed the JEDEC requirement by one clock. This maximum absolute
interval is to allow future support for DLL updates, internal to the DDR SDRAM, to be
restricted to AUTO REFRESH cycles, without allowing excessive drift in tAC between
updates.

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Operations

Although not a JEDEC requirement, to provide for future functionality features, CKE
must be active (HIGH) during the AUTO REFRESH period. The AUTO REFRESH period
begins when the AUTO REFRESH command is registered and ends tRFC later.

Figure 52: Auto Refresh Mode

T0 T1 T2 T3 T4 Ta0 Ta1 Tb0 Tb1 Tb2

(( ((
CK# )) ))
(( ((
CK )) ))
tIS tIH CK tCH tCL
(( ((
)) ))
CKE Valid (( (( Valid
tIS tIH )) ))
(( ((
)) ))
Command NOP1 PRE NOP1 NOP1 AR (( NOP1,2 AR3 (( NOP1,2 NOP1 ACT
)) ))
(( ((
)) ))
Address RA
(( ((
)) ))
All banks (( ((
)) ))
A10 (( (( RA
One bank )) ))
tIS tIH
(( ((
)) ))
BA[1:0] Bank(s)4 (( ((
BA
)) ))
5 (( ((
DQS )) ))
(( ((
)) ))
(( ((
5 )) ))
DQ
(( ((
)) ))
(( ((
5 )) ))
DM (( ((
)) ))
tRP tRFC tRFC

Don’t Care

Notes: 1. NOP commands are shown for ease of illustration; other valid commands may be possible at
these times. CKE must be active during clock-positive transitions.
2. NOP or COMMAND INHIBIT are the only commands allowed until after tRFC time; CKE must
be active during clock-positive transitions.
3. The second AUTO REFRESH is not required and is only shown as an example of two back-to-
back AUTO REFRESH commands.
4. “Don’t Care” if A10 is HIGH at this point; A10 must be HIGH if more than one bank is active
(that is, must precharge all active banks).
5. DM, DQ, and DQS signals are all “Don’t Care”/High-Z for the operations shown.

SELF REFRESH
When in the self refresh mode, the DDR SDRAM retains data without external clocking.
The DLL is automatically disabled upon entering SELF REFRESH and is automatically
enabled upon exiting SELF REFRESH (a DLL reset and 200 clock cycles must then occur
before a READ command can be issued). Input signals except CKE are “Don’t Care”
during SELF REFRESH. VREF voltage is also required for the full duration of SELF
REFRESH.
The procedure for exiting SELF REFRESH requires a sequence of commands. First, CK
and CK# must be stable prior to CKE going back HIGH. Once CKE is HIGH, the DDR
SDRAM must have NOP commands issued for tXSNR because time is required for the
completion of any internal refresh in progress. A simple algorithm for meeting both
refresh and DLL requirements is to apply NOPs for tXSRD time, then a DLL RESET (via

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Operations

the extended mode register) and NOPs for 200 additional clock cycles before applying a
READ. Any command other than a READ can be performed tXSNR (MIN) after the DLL
reset. NOP or DESELECT commands must be issued during the tXSNR (MIN) time.
Self refresh is not supported on automotive tempature (AAT) devices.

Figure 53: Self Refresh Mode

T0 T11 Ta01 Ta1 Ta2 Tb1 Tb2 Tc1

(( (( ((
CK# )) ))
))
CK1 (( ((
tCH tCL )) (( ))
tCK ))
tIS tIH tIS t IS ((
((
)) ))
CKE (( (( ((
)) )) ))
tIS tIH
(( (( ((
)) ))
Command2 NOP AR )) NOP NOP Valid3 Valid Valid
(( (( ((
)) )) ))
tIS tIH
(( (( ((
)) )) ))
Address (( Valid Valid Valid
(( ((
)) )) ))

(( (( ((
DQS )) )) ))
(( (( ((
)) )) ))
(( (( ((
)) )) ))
DQ (( ((
(( ))
)) ))

(( ((
(( )) ))
DM ))
(( ((
(( )) ))
))

tRP4 tXSNR5

tXSRD6

Enter self refresh mode7 Exit self refresh mode7 Don’t Care

Notes: 1. Clock must be stable until after the SELF REFRESH command has been registered. A change
in clock frequency is allowed before Ta0, provided it is within the specified tCK limits.
Regardless, the clock must be stable before exiting self refresh mode—that is, the clock
must be cycling within specifications by Ta0.
2. NOPs are interchangeable with DESELECT commands.
3. AUTO REFRESH is not required at this point but is highly recommended.
4. Device must be in the all banks idle state prior to entering self refresh mode.
5. tXSNR is required before any non-READ command can be applied; that is only NOP or DESE-
LECT commands are allowed until Tb1.
6. tXSRD (200 cycles of a valid clock with CKE = HIGH) is required before any READ command
can be applied.
7. As a general rule, any time self refresh mode is exited, the DRAM may not re-enter the self
refresh mode until all rows have been refreshed via the AUTO REFRESH command at the
distributed refresh rate, tREFI, or faster. However, the self refresh mode may be re-entered
anytime after exiting if each of the following conditions is met:
7a. The DRAM had been in the self refresh mode for a minimum of 200ms prior to exiting.
7b. tXSNR and tXSRD are not violated.
7c. At least two AUTO REFRESH commands are performed during each tREFI interval while
the DRAM remains out of self refresh mode.
8. If the clock frequency is changed during self refresh mode, a DLL reset is required upon exit.
9. Once the device is initialized, VREF must always be powered within specified range.

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Operations

Power-down (CKE Not Active)

Unlike SDR SDRAMs, DDR SDRAMs require CKE to be active at all times an access is in
progress, from the issuing of a READ or WRITE command, until completion of the
access. Thus a clock suspend is not supported. For READs, an access completion is
defined when the read postamble is satisfied; for WRITEs, when the write recovery time
(tWR) is satisfied.
Power-down, as shown in Figure 54 on page 90, is entered when CKE is registered LOW
and all criteria in Table 31 on page 46 are met. If power-down occurs when all banks are
idle, this mode is referred to as precharge power-down; if power-down occurs when a
row is active in any bank, this mode is referred to as active power-down. Entering power-
down deactivates the input and output buffers, excluding CK, CK#, and CKE. For
maximum power savings, the DLL is frozen during precharge power-down mode. Exiting
power-down requires the device to be at the same voltage and frequency as when it
entered power-down. However, power-down duration is limited by the refresh require-
ments of the device (tREFC or tREFCAT ).
While in power-down, CKE LOW and a stable clock signal must be maintained at the
inputs of the DDR SDRAM, while all other input signals are “Don’t Care.” The power-
down state is synchronously exited when CKE is registered HIGH (in conjunction with a
NOP or DESELECT command). A valid executable command may be applied one clock
cycle later.

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Operations

Figure 54: Power-Down Mode

T0 T1 T2 Ta0 Ta1 Ta2

((
CK# ))
CK ((
tCK tCH tCL ))

tIS tIH tIS tIS

1
CKE ((
tIS tIH ))

((
))
Command Valid2 NOP NOP Valid
((
))
tIS tIH
((
))
Address Valid Valid
((
))
((
))
DQS
((
))
((
))
DQ ((
))
((
))
DM ((
))
tREFC
Enter 3 Exit
power-down power-down
mode mode
Don’t Care

Notes: 1. Once initialized, VREF must always be powered within the specified range.
2. If this command is a PRECHARGE (or if the device is already in the idle state), then the
power-down mode shown is precharge power-down. If this command is an ACTIVE (or if at
least one row is already active), then the power-down mode shown is active power-down.
3. No column accesses are allowed to be in progress at the time power-down is entered.

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Micron and the Micron logo are trademarks of Micron Technology, Inc.All other trademarks are the property of their respective owners.
This data sheet contains minimum and maximum limits specified over the power supply and temperature range set forth herein. Although
considered final, these specifications are subject to change, as further product development and data characterization sometimes occur.

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