2Gb: x16, x32, x64 Automotive LPDDR2 SDRAM
Features
Automotive LPDDR2 SDRAM
MT42L128M16, MT42L64M32, MT42L64M64
Features
Options
• VDD2: 1.2V
• Configuration
– 16 Meg x 16 x 8 banks
– 8 Meg x 32 x 8 banks
– 8 Meg x 32 x 8 banks x 2 die
• Device type
– LPDDR2 single die/dual die
• FBGA “green” package
– 134-ball FBGA (10mm x
11.5mm)
– 168-ball FBGA (12mm x 12mm)
– 216-ball FBGA (12mm x 12mm)
• Timing – cycle time
– 1.875ns @ RL = 8
– 2.5ns @ RL = 6
– 3.0ns @ RL = 5
• Special options
– Standard
– Automotive grade (Package-level
burn-in)
• Operating temperature range
– From –30°C to +85°C
– From –40°C to +85°C
– From –40°C to +105°C
• Revision
• Ultra low-voltage core and I/O power supplies
– VDD2 = 1.14–1.30V
– VDDCA/VDDQ = 1.14–1.30V
– VDD1 = 1.70–1.95V
• Clock frequency range
– 533–10 MHz (data rate range: 1066–20 Mb/s/pin)
• Four-bit prefetch DDR architecture
• Eight internal banks for concurrent operation
• Multiplexed, double data rate, command/address
inputs; commands entered on every CK edge
• Bidirectional/differential data strobe per byte of
data (DQS/DQS#)
• Programmable READ and WRITE latencies (RL/WL)
• Programmable burst lengths: 4, 8, or 16
• Per-bank refresh for concurrent operation
• On-chip temperature sensor to control self refresh
rate
• Partial-array self refresh (PASR)
• Deep power-down mode (DPD)
• Selectable output drive strength (DS)
• Clock stop capability
• RoHS-compliant, “green” packaging
Table 1: Key Timing Parameters
Speed Clock Rate Data Rate
Grade
(MHz)
(Mb/s/pin)
Note:
RL
WL
tRCD/tRP1
-18
533
1066
8
4
Typical
-25
400
800
6
3
Typical
-3
333
667
5
2
Typical
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1
Marking
L
128M16
64M32
64M64
D1, D2
TK
LF
LL
-18
-25
-3
A
WT
IT
AT
:C
1. For Fast tRCD/tRP, contact factory.
Micron Technology, Inc. reserves the right to change products or specifications without notice.
© 2014 Micron Technology, Inc. All rights reserved.
Products and specifications discussed herein are subject to change by Micron without notice.
2Gb: x16, x32, x64 Automotive LPDDR2 SDRAM
Features
Table 2: Single Channel, Single Rank S4 Configuration Addressing
Architecture
Die configuration
Row addressing
Column addressing
Number of die
Die per rank
Ranks per
Note:
channel1
Chip Select
128 Meg x 16
64 Meg x 32
CS0#
16 Meg x 16 x 8 banks
8 Meg x 32 x 8 banks
CS1#
n/a
n/a
–
16K (A[13:0])
16K (A[13:0])
CS0#
1K (A[9:0])
512 (A[8:0])
CS1#
n/a
n/a
–
1
1
CS0#
1
1
CS1#
0
0
–
1
1
1. A channel is a complete LPDRAM interface, including command/address and data pins.
Table 3: Dual Channel, Single Rank S4 Configuration Addressing
Architecture
Die configuration
Row addressing
Column addressing
Number of die
Die per rank
Ranks per
Note:
channel1
Chip Select
64 Meg x 64
CS0#
8 Meg x 32 x 8 banks
CS1#
n/a
–
16K (A[13:0])
CS0#
512 (A[8:0])
CS1#
n/a
–
2
CS0#
2
CS1#
0
–
1
1. A channel is a complete LPDRAM interface, including command/address and data pins.
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© 2014 Micron Technology, Inc. All rights reserved.
2Gb: x16, x32, x64 Automotive LPDDR2 SDRAM
Features
Figure 1: 2Gb LPDDR2 Part Numbering
MT
42
L
128M16
D1
LF
-25
A
WT
:C
Design Revision
Micron Technology
:C = First generation
Product Family
Operating Temperature
42 = Mobile LPDDR2 SDRAM
WT = –30°C to +85°C
IT = –40°C to +85°C
AT = –40°C to +105°C
Operating Voltage
L = 1.2V
Special Options
Configuration
A = Automotive grade
128M16 = 128 Meg x 16
Cycle Time
64M32 = 128 Meg x 32
64M64 = 64 Meg x 64
-18 = 1.875ns, tCK RL = 8
-25 = 2.5ns, tCK RL = 6
-3 = 3.0ns, tCK RL = 5
Device Type
Package Codes
D1 = LPDDR2 single-die
D2 = LPDDR2 dual-die
LF = FBGA 168-ball 12 x 12
LL = FBGA 216-ball 12 x 12
TK = FBGA 134-ball 10 x 11.5
FBGA Part Marking Decoder
Due to space limitations, FBGA-packaged components have an abbreviated part marking that is different from the
part number. Micron’s FBGA part marking decoder is available at www.micron.com/decoder.
Table 4: Package Codes and Descriptions
Package Code
BGA
SB
Package-Z
MTG Number
TK
134-ball
SAC 305
0.7
MTG-1038
LF
168-ball
SAC 305
0.75
LL
216-ball
SAC 305
0.8
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MTG-832
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© 2014 Micron Technology, Inc. All rights reserved.
2Gb: x16, x32, x64 Automotive LPDDR2 SDRAM
Features
Contents
General Description .......................................................................................................................................
General Notes ............................................................................................................................................
IDD Specifications ...........................................................................................................................................
Package Block Diagrams .................................................................................................................................
Package Dimensions .......................................................................................................................................
Ball Assignments and Descriptions .................................................................................................................
Functional Description ...................................................................................................................................
Power-Up .......................................................................................................................................................
Initialization After RESET (Without Voltage Ramp) ......................................................................................
Power-Off .......................................................................................................................................................
Uncontrolled Power-Off ..............................................................................................................................
Mode Register Definition ................................................................................................................................
Mode Register Assignments and Definitions ................................................................................................
ACTIVATE Command .....................................................................................................................................
8-Bank Device Operation ............................................................................................................................
Read and Write Access Modes .........................................................................................................................
Burst READ Command ...................................................................................................................................
READs Interrupted by a READ .....................................................................................................................
Burst WRITE Command ..................................................................................................................................
WRITEs Interrupted by a WRITE .................................................................................................................
BURST TERMINATE Command ......................................................................................................................
Write Data Mask .............................................................................................................................................
PRECHARGE Command .................................................................................................................................
READ Burst Followed by PRECHARGE .........................................................................................................
WRITE Burst Followed by PRECHARGE .......................................................................................................
Auto Precharge ...........................................................................................................................................
READ Burst with Auto Precharge .................................................................................................................
WRITE Burst with Auto Precharge ...............................................................................................................
REFRESH Command ......................................................................................................................................
REFRESH Requirements .............................................................................................................................
SELF REFRESH Operation ...............................................................................................................................
Partial-Array Self Refresh – Bank Masking ....................................................................................................
Partial-Array Self Refresh – Segment Masking ..............................................................................................
MODE REGISTER READ .................................................................................................................................
Temperature Sensor ...................................................................................................................................
DQ Calibration ...........................................................................................................................................
MODE REGISTER WRITE Command ...............................................................................................................
MRW RESET Command ..............................................................................................................................
MRW ZQ Calibration Commands ................................................................................................................
ZQ External Resistor Value, Tolerance, and Capacitive Loading .....................................................................
Power-Down ..................................................................................................................................................
Deep Power-Down .........................................................................................................................................
Input Clock Frequency Changes and Stop Events .............................................................................................
Input Clock Frequency Changes and Clock Stop with CKE LOW ...................................................................
Input Clock Frequency Changes and Clock Stop with CKE HIGH ..................................................................
NO OPERATION Command ............................................................................................................................
Simplified Bus Interface State Diagram ........................................................................................................
Truth Tables ...................................................................................................................................................
Electrical Specifications ..................................................................................................................................
Absolute Maximum Ratings ........................................................................................................................
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10
10
11
16
18
21
25
26
28
28
29
29
29
40
40
41
41
48
48
51
51
53
54
55
56
57
57
58
60
66
68
69
70
71
73
75
77
77
78
80
80
87
88
88
89
89
89
91
99
99
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2Gb: x16, x32, x64 Automotive LPDDR2 SDRAM
Features
Input/Output Capacitance .......................................................................................................................... 99
Electrical Specifications – IDD Specifications and Conditions ........................................................................... 100
AC and DC Operating Conditions ................................................................................................................... 103
AC and DC Logic Input Measurement Levels for Single-Ended Signals ............................................................. 105
VREF Tolerances ......................................................................................................................................... 106
Input Signal .............................................................................................................................................. 107
AC and DC Logic Input Measurement Levels for Differential Signals ................................................................ 109
Single-Ended Requirements for Differential Signals .................................................................................... 110
Differential Input Crosspoint Voltage ......................................................................................................... 112
Input Slew Rate ......................................................................................................................................... 113
Output Characteristics and Operating Conditions ........................................................................................... 113
Single-Ended Output Slew Rate .................................................................................................................. 114
Differential Output Slew Rate ..................................................................................................................... 115
HSUL_12 Driver Output Timing Reference Load ......................................................................................... 117
Output Driver Impedance .............................................................................................................................. 117
Output Driver Impedance Characteristics with ZQ Calibration .................................................................... 118
Output Driver Temperature and Voltage Sensitivity ..................................................................................... 119
Output Impedance Characteristics Without ZQ Calibration ......................................................................... 119
Clock Specification ........................................................................................................................................ 123
tCK(abs), tCH(abs), and tCL(abs) ................................................................................................................ 124
Clock Period Jitter .......................................................................................................................................... 124
Clock Period Jitter Effects on Core Timing Parameters ................................................................................. 124
Cycle Time Derating for Core Timing Parameters ........................................................................................ 125
Clock Cycle Derating for Core Timing Parameters ....................................................................................... 125
Clock Jitter Effects on Command/Address Timing Parameters ..................................................................... 125
Clock Jitter Effects on READ Timing Parameters .......................................................................................... 125
Clock Jitter Effects on WRITE Timing Parameters ........................................................................................ 126
Refresh Requirements .................................................................................................................................... 127
AC Timing ..................................................................................................................................................... 128
CA and CS# Setup, Hold, and Derating ........................................................................................................... 134
Data Setup, Hold, and Slew Rate Derating ....................................................................................................... 141
Revision History ............................................................................................................................................ 148
Rev. D – 04/15 ............................................................................................................................................ 148
Rev. C – 09/14 ............................................................................................................................................ 148
Rev. B – 08/14 ............................................................................................................................................ 148
Rev. A – 05/14 ............................................................................................................................................ 148
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© 2014 Micron Technology, Inc. All rights reserved.
2Gb: x16, x32, x64 Automotive LPDDR2 SDRAM
Features
List of Figures
Figure 1: 2Gb LPDDR2 Part Numbering ............................................................................................................ 3
Figure 2: V DD1Typical Self Refresh Current vs. Temperature ............................................................................. 15
Figure 3: V DD2 Typical Self Refresh Current vs. Temperature ............................................................................ 15
Figure 4: Single Rank, Single Channel Package Block Diagram ......................................................................... 16
Figure 5: Single Rank, Dual Channel Package Block Diagram ........................................................................... 17
Figure 6: 134-Ball FBGA – 10mm x 11.5mm Single-Die (Package Code TK) ....................................................... 18
Figure 7: 168-Ball FBGA – 12mm x 12mm Single-Die (Package Code LF) .......................................................... 19
Figure 8: 216-Ball FBGA – 12mm x 12mm (Package Codes LL) ......................................................................... 20
Figure 9: 134-Ball FBGA (x32) ......................................................................................................................... 21
Figure 10: 168-Ball FBGA – 12mm x 12mm ..................................................................................................... 22
Figure 11: 216-Ball 2-Channel FBGA – 12mm x 12mm ..................................................................................... 23
Figure 12: Functional Block Diagram ............................................................................................................. 25
Figure 13: Voltage Ramp and Initialization Sequence ...................................................................................... 28
Figure 14: ACTIVATE Command .................................................................................................................... 40
Figure 15: tFAW Timing (8-Bank Devices) ....................................................................................................... 41
Figure 16: READ Output Timing – tDQSCK (MAX) ........................................................................................... 42
Figure 17: READ Output Timing – tDQSCK (MIN) ........................................................................................... 42
Figure 18: Burst READ – RL = 5, BL = 4, tDQSCK > tCK ..................................................................................... 43
Figure 19: Burst READ – RL = 3, BL = 8, tDQSCK < tCK ..................................................................................... 43
Figure 20: tDQSCKDL Timing ........................................................................................................................ 44
Figure 21: tDQSCKDM Timing ....................................................................................................................... 45
Figure 22: tDQSCKDS Timing ......................................................................................................................... 46
Figure 23: Burst READ Followed by Burst WRITE – RL = 3, WL = 1, BL = 4 ......................................................... 47
Figure 24: Seamless Burst READ – RL = 3, BL = 4, tCCD = 2 .............................................................................. 47
Figure 25: READ Burst Interrupt Example – RL = 3, BL = 8, tCCD = 2 ................................................................. 48
Figure 26: Data Input (WRITE) Timing ........................................................................................................... 49
Figure 27: Burst WRITE – WL = 1, BL = 4 ......................................................................................................... 49
Figure 28: Burst WRITE Followed by Burst READ – RL = 3, WL = 1, BL = 4 ......................................................... 50
Figure 29: Seamless Burst WRITE – WL = 1, BL = 4, tCCD = 2 ............................................................................ 50
Figure 30: WRITE Burst Interrupt Timing – WL = 1, BL = 8, tCCD = 2 ................................................................ 51
Figure 31: Burst WRITE Truncated by BST – WL = 1, BL = 16 ............................................................................ 52
Figure 32: Burst READ Truncated by BST – RL = 3, BL = 16 ............................................................................... 53
Figure 33: Data Mask Timing ......................................................................................................................... 53
Figure 34: Write Data Mask – Second Data Bit Masked .................................................................................... 54
Figure 35: READ Burst Followed by PRECHARGE – RL = 3, BL = 8, RU(tRTP(MIN)/tCK) = 2 ................................ 55
Figure 36: READ Burst Followed by PRECHARGE – RL = 3, BL = 4, RU(tRTP(MIN)/tCK) = 3 ................................ 56
Figure 37: WRITE Burst Followed by PRECHARGE – WL = 1, BL = 4 .................................................................. 57
Figure 38: READ Burst with Auto Precharge – RL = 3, BL = 4, RU(tRTP(MIN)/tCK) = 2 ........................................ 58
Figure 39: WRITE Burst with Auto Precharge – WL = 1, BL = 4 .......................................................................... 59
Figure 40: Regular Distributed Refresh Pattern ............................................................................................... 63
Figure 41: Supported Transition from Repetitive REFRESH Burst .................................................................... 64
Figure 42: Nonsupported Transition from Repetitive REFRESH Burst .............................................................. 65
Figure 43: Recommended Self Refresh Entry and Exit ..................................................................................... 66
Figure 44: tSRF Definition .............................................................................................................................. 67
Figure 45: All-Bank REFRESH Operation ........................................................................................................ 67
Figure 46: Per-Bank REFRESH Operation ....................................................................................................... 68
Figure 47: SELF REFRESH Operation .............................................................................................................. 69
Figure 48: MRR Timing – RL = 3, tMRR = 2 ...................................................................................................... 71
Figure 49: READ to MRR Timing – RL = 3, tMRR = 2 ......................................................................................... 72
Figure 50: Burst WRITE Followed by MRR – RL = 3, WL = 1, BL = 4 ................................................................... 73
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2Gb: x16, x32, x64 Automotive LPDDR2 SDRAM
Features
Figure 51:
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Figure 90:
Figure 91:
Temperature Sensor Timing ........................................................................................................... 75
MR32 and MR40 DQ Calibration Timing – RL = 3, tMRR = 2 ............................................................. 76
MODE REGISTER WRITE Timing – RL = 3, tMRW = 5 ....................................................................... 77
ZQ Timings ................................................................................................................................... 79
Power-Down Entry and Exit Timing ................................................................................................ 81
CKE Intensive Environment ........................................................................................................... 81
REFRESH-to-REFRESH Timing in CKE Intensive Environments ...................................................... 81
READ to Power-Down Entry ........................................................................................................... 82
READ with Auto Precharge to Power-Down Entry ............................................................................ 83
WRITE to Power-Down Entry ......................................................................................................... 84
WRITE with Auto Precharge to Power-Down Entry .......................................................................... 85
REFRESH Command to Power-Down Entry .................................................................................... 86
ACTIVATE Command to Power-Down Entry ................................................................................... 86
PRECHARGE Command to Power-Down Entry ............................................................................... 86
MRR Command to Power-Down Entry ........................................................................................... 87
MRW Command to Power-Down Entry .......................................................................................... 87
Deep Power-Down Entry and Exit Timing ....................................................................................... 88
Simplified Bus Interface State Diagram ........................................................................................... 90
V REF DC Tolerance and V REF AC Noise Limits ................................................................................. 106
LPDDR2-466 to LPDDR2-1066 Input Signal ................................................................................... 107
LPDDR2-200 to LPDDR2-400 Input Signal ..................................................................................... 108
Differential AC Swing Time and tDVAC .......................................................................................... 109
Single-Ended Requirements for Differential Signals ....................................................................... 111
V IX Definition ............................................................................................................................... 112
Differential Input Slew Rate Definition for CK, CK#, DQS, and DQS# ............................................... 113
Single-Ended Output Slew Rate Definition ..................................................................................... 114
Differential Output Slew Rate Definition ........................................................................................ 115
Overshoot and Undershoot Definition ........................................................................................... 116
HSUL_12 Driver Output Reference Load for Timing and Slew Rate ................................................. 117
Output Driver ............................................................................................................................... 118
Output Impedance = 240 Ohms, I-V Curves After ZQRESET ............................................................ 121
Output Impedance = 240 Ohms, I-V Curves After Calibration ......................................................... 122
Command Input Setup and Hold Timing ....................................................................................... 134
Typical Slew Rate and tVAC – tIS for CA and CS# Relative to Clock ................................................... 137
Typical Slew Rate – tIH for CA and CS# Relative to Clock ................................................................. 138
Tangent Line – tIS for CA and CS# Relative to Clock ........................................................................ 139
Tangent Line – tIH for CA and CS# Relative to Clock ....................................................................... 140
Typical Slew Rate and tVAC – tDS for DQ Relative to Strobe ............................................................. 144
Typical Slew Rate – tDH for DQ Relative to Strobe ........................................................................... 145
Tangent Line – tDS for DQ with Respect to Strobe .......................................................................... 146
Tangent Line – tDH for DQ with Respect to Strobe .......................................................................... 147
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© 2014 Micron Technology, Inc. All rights reserved.
2Gb: x16, x32, x64 Automotive LPDDR2 SDRAM
Features
List of Tables
Table 1: Key Timing Parameters ....................................................................................................................... 1
Table 2: Single Channel, Single Rank S4 Configuration Addressing .................................................................... 2
Table 3: Dual Channel, Single Rank S4 Configuration Addressing ...................................................................... 2
Table 4: Package Codes and Descriptions ......................................................................................................... 3
Table 5: 128 Meg x 16 IDD Specifications ......................................................................................................... 11
Table 6: 64 Meg x 32 IDD Specifications ........................................................................................................... 12
Table 7: IDD6 Partial-Array Self Refresh Current ............................................................................................... 14
Table 8: Ball/Pad Descriptions ....................................................................................................................... 24
Table 9: Initialization Timing Parameters ....................................................................................................... 28
Table 10: Power-Off Timing ............................................................................................................................ 29
Table 11: Mode Register Assignments ............................................................................................................. 30
Table 12: MR0 Device Information (MA[7:0] = 00h) ......................................................................................... 31
Table 13: MR0 Op-Code Bit Definitions .......................................................................................................... 31
Table 14: MR1 Device Feature 1 (MA[7:0] = 01h) .............................................................................................. 31
Table 15: MR1 Op-Code Bit Definitions .......................................................................................................... 31
Table 16: Burst Sequence by Burst Length (BL), Burst Type (BT), and Wrap Control (WC) ................................. 32
Table 17: No-Wrap Restrictions ...................................................................................................................... 33
Table 18: MR2 Device Feature 2 (MA[7:0] = 02h) .............................................................................................. 33
Table 19: MR2 Op-Code Bit Definitions .......................................................................................................... 34
Table 20: MR3 I/O Configuration 1 (MA[7:0] = 03h) ......................................................................................... 34
Table 21: MR3 Op-Code Bit Definitions .......................................................................................................... 34
Table 22: MR4 Device Temperature (MA[7:0] = 04h) ........................................................................................ 34
Table 23: MR4 Op-Code Bit Definitions .......................................................................................................... 35
Table 24: MR5 Basic Configuration 1 (MA[7:0] = 05h) ...................................................................................... 35
Table 25: MR5 Op-Code Bit Definitions .......................................................................................................... 35
Table 26: MR6 Basic Configuration 2 (MA[7:0] = 06h) ...................................................................................... 36
Table 27: MR6 Op-Code Bit Definitions .......................................................................................................... 36
Table 28: MR7 Basic Configuration 3 (MA[7:0] = 07h) ...................................................................................... 36
Table 29: MR7 Op-Code Bit Definitions .......................................................................................................... 36
Table 30: MR8 Basic Configuration 4 (MA[7:0] = 08h) ...................................................................................... 36
Table 31: MR8 Op-Code Bit Definitions .......................................................................................................... 36
Table 32: MR9 Test Mode (MA[7:0] = 09h) ....................................................................................................... 37
Table 33: MR10 Calibration (MA[7:0] = 0Ah) ................................................................................................... 37
Table 34: MR10 Op-Code Bit Definitions ........................................................................................................ 37
Table 35: MR[11:15] Reserved (MA[7:0] = 0Bh–0Fh) ......................................................................................... 38
Table 36: MR16 PASR Bank Mask (MA[7:0] = 010h) .......................................................................................... 38
Table 37: MR16 Op-Code Bit Definitions ........................................................................................................ 38
Table 38: MR17 PASR Segment Mask (MA[7:0] = 011h) .................................................................................... 38
Table 39: MR17 PASR Segment Mask Definitions ............................................................................................ 38
Table 40: MR17 PASR Row Address Ranges in Masked Segments ...................................................................... 38
Table 41: Reserved Mode Registers ................................................................................................................. 39
Table 42: MR63 RESET (MA[7:0] = 3Fh) – MRW Only ....................................................................................... 39
Table 43: Bank Selection for PRECHARGE by Address Bits ............................................................................... 55
Table 44: PRECHARGE and Auto Precharge Clarification ................................................................................. 59
Table 45: REFRESH Command Scheduling Separation Requirements .............................................................. 61
Table 46: Bank and Segment Masking Example ............................................................................................... 70
Table 47: Temperature Sensor Definitions and Operating Conditions .............................................................. 74
Table 48: Data Calibration Pattern Description ............................................................................................... 76
Table 49: Truth Table for MRR and MRW ........................................................................................................ 77
Table 50: Command Truth Table .................................................................................................................... 91
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© 2014 Micron Technology, Inc. All rights reserved.
2Gb: x16, x32, x64 Automotive LPDDR2 SDRAM
Features
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Table 88:
Table 89:
Table 90:
Table 91:
Table 92:
Table 93:
Table 94:
Table 95:
Table 96:
Table 97:
CKE Truth Table .............................................................................................................................. 92
Current State Bank n to Command to Bank n Truth Table ................................................................. 93
Current State Bank n to Command to Bank m Truth Table ................................................................ 95
DM Truth Table ............................................................................................................................... 98
Absolute Maximum DC Ratings ....................................................................................................... 99
Input/Output Capacitance .............................................................................................................. 99
Switching for CA Input Signals ........................................................................................................ 100
Switching for IDD4R ......................................................................................................................... 101
Switching for IDD4W ........................................................................................................................ 101
IDD Specification Parameters and Operating Conditions .................................................................. 101
Recommended DC Operating Conditions ....................................................................................... 103
Input Leakage Current ................................................................................................................... 104
Operating Temperature Range ........................................................................................................ 104
Single-Ended AC and DC Input Levels for CA and CS# Inputs ........................................................... 105
Single-Ended AC and DC Input Levels for CKE ................................................................................ 105
Single-Ended AC and DC Input Levels for DQ and DM ..................................................................... 105
Differential AC and DC Input Levels ................................................................................................ 109
CK/CK# and DQS/DQS# Time Requirements Before Ringback ( tDVAC) ............................................ 110
Single-Ended Levels for CK, CK#, DQS, DQS# .................................................................................. 111
Crosspoint Voltage for Differential Input Signals (CK, CK#, DQS, DQS#) ........................................... 112
Differential Input Slew Rate Definition ............................................................................................ 113
Single-Ended AC and DC Output Levels .......................................................................................... 113
Differential AC and DC Output Levels ............................................................................................. 114
Single-Ended Output Slew Rate Definition ...................................................................................... 114
Single-Ended Output Slew Rate ...................................................................................................... 114
Differential Output Slew Rate Definition ......................................................................................... 115
Differential Output Slew Rate ......................................................................................................... 115
AC Overshoot/Undershoot Specification ......................................................................................... 116
Output Driver DC Electrical Characteristics with ZQ Calibration ...................................................... 118
Output Driver Sensitivity Definition ................................................................................................ 119
Output Driver Temperature and Voltage Sensitivity ......................................................................... 119
Output Driver DC Electrical Characteristics Without ZQ Calibration ................................................ 119
I-V Curves ..................................................................................................................................... 120
Definitions and Calculations .......................................................................................................... 123
tCK(abs), tCH(abs), and tCL(abs) Definitions ................................................................................... 124
Refresh Requirement Parameters (Per Density) ............................................................................... 127
AC Timing ..................................................................................................................................... 128
CA and CS# Setup and Hold Base Values (>400 MHz, 1 V/ns Slew Rate) ............................................ 135
CA and CS# Setup and Hold Base Values ( V IH(AC) and < V IL(AC) ....................................................... 136
Data Setup and Hold Base Values (>400 MHz, 1 V/ns Slew Rate) ....................................................... 141
Data Setup and Hold Base Values ( V IH(AC) or < V IL(AC) ......................................................... 143
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2Gb: x16, x32, x64 Automotive LPDDR2 SDRAM
General Description
General Description
The 4Gb Mobile Low-Power DDR2 SDRAM (LPDDR2) is a high-speed CMOS, dynamic
random-access memory containing 4,294,967,296-bits. The LPDDR2-S4 device is internally configured as an eight-bank DRAM. Each of the x16’s 536,870,912-bit banks is organized as 16,384 rows by 2048 columns by 16 bits. Each of the x32’s 536,870,912-bit
banks is organized as 16,384 rows by 1024 columns by 32 bits.
General Notes
Throughout the data sheet, figures and text refer to DQs as “DQ.” DQ should be interpreted as any or all DQ collectively, unless specifically stated otherwise.
“DQS” and “CK” should be interpreted as DQS, DQS# and CK, CK# respectively, unless
specifically stated otherwise. “BA” includes all BA pins used for a given density.
In timing diagrams, “CMD” is used as an indicator only. Actual signals occur on CA[9:0].
VREF indicates V REFCA and V REFDQ.
Complete functionality may be described throughout the entire document. 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.
Any functionality not specifically stated herein is considered undefined, illegal, is not
supported, and will result in unknown operation.
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2Gb: x16, x32, x64 Automotive LPDDR2 SDRAM
IDD Specifications
IDD Specifications
Table 5: 128 Meg x 16 IDD Specifications
VDD2, VDDQ, VDDCA = 1.14–1.30V; VDD1 = 1.70–1.95V
Speed Grade
Supply
-18
-25
-3
Unit
IDD01
Parameter
VDD1
15
15
15
mA
IDD02
VDD2
70
70
70
IDD0,in
VDDCA + VDDQ
7
6
6
IDD2P1
VDD1
600
600
600
IDD2P2
VDD2
800
800
800
IDD2P,in
VDDCA + VDDQ
50
50
50
IDD2PS1
VDD1
600
600
600
IDD2PS2
VDD2
800
800
800
IDD2PS,in
VDDCA + VDDQ
50
50
50
IDD2N1
VDD1
2
2
2
IDD2N2
VDD2
30
30
30
μA
μA
mA
IDD2N,in
VDDCA + VDDQ
7
6
6
IDD2NS1
VDD1
1.7
1.7
1.7
IDD2NS2
VDD2
27
27
27
IDD2NS,in
VDDCA + VDDQ
6
6
6
IDD3P1
VDD1
1200
1200
1200
µA
IDD3P2
VDD2
8
8
8
mA
IDD3P,in
VDDCA + VDDQ
150
150
150
µA
IDD3PS1
VDD1
1200
1200
1200
µA
mA
IDD3PS2
VDD2
8
8
8
mA
IDD3PS,in
VDDCA + VDDQ
150
150
150
µA
IDD3N1
VDD1
2.5
2.5
2.5
mA
IDD3N2
VDD2
30
30
30
IDD3N,in
VDDCA + VDDQ
7
6
6
IDD3NS1
VDD1
2
2
2
IDD3NS2
VDD2
27
27
27
IDD3NS,in
VDDCA + VDDQ
6
6
6
IDD4R1
VDD1
3
3
3
IDD4R2
VDD2
220
194
178
IDD4R,in
VDDCA
6
6
6
IDD4W1
VDD1
10
10
10
IDD4W2
VDD2
190
185
170
IDD4W,in
VDDCA + VDDQ
25
25
25
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11
mA
mA
mA
Micron Technology, Inc. reserves the right to change products or specifications without notice.
© 2014 Micron Technology, Inc. All rights reserved.
2Gb: x16, x32, x64 Automotive LPDDR2 SDRAM
IDD Specifications
Table 5: 128 Meg x 16 IDD Specifications (Continued)
VDD2, VDDQ, VDDCA = 1.14–1.30V; VDD1 = 1.70–1.95V
Speed Grade
Parameter
Supply
-18
-25
-3
Unit
VDD1
40
40
40
mA
IDD52
VDD2
150
150
150
IDD5,in
VDDCA + VDDQ
8
6
6
IDD5PB1
VDD1
5
5
5
IDD5PB2
VDD2
50
50
50
IDD5PB,in
VDDCA + VDDQ
8
8
8
IDD5PBET1
VDD1
10.5
10.5
10.5
IDD5PBET2
VDD2
80
80
80
IDD5PB,ETin
VDDCA + VDDQ
8
8
8
IDD51
mA
mA
IDD5AB1
VDD1
5
5
5
IDD5AB2
VDD2
50
50
50
IDD5AB,in
VDDCA + VDDQ
8
8
8
IDD5ABET1
VDD1
10.5
10.5
10.5
IDD5ABET2
VDD2
80
80
80
IDD5AB,ETin
VDDCA + VDDQ
8
8
8
IDD61
VDD1
1000
1000
1000
IDD62
VDD2
3200
3200
3200
IDD6,in
VDDCA + VDDQ
50
50
50
IDD6ET1
VDD1
3100
3100
3100
µA
IDD6ET2
VDD2
13.7
13.7
13.7
mA
IDD6,ETin
VDDCA + VDDQ
90
90
90
µA
µA
IDD81
VDD1
25
25
25
IDD82
VDD2
100
100
100
IDD8,in
VDDCA + VDDQ
100
100
100
mA
mA
µA
Table 6: 64 Meg x 32 IDD Specifications
VDD2, VDDQ, VDDCA = 1.14–1.30V; VDD1 = 1.70–1.95V
Speed Grade
Parameter
Supply
-18
-25
-3
IDD01
VDD1
15
15
15
IDD02
VDD2
70
70
70
IDD0,in
VDDCA + VDDQ
7
6
6
IDD2P1
VDD1
600
600
600
IDD2P2
VDD2
800
800
800
IDD2P,in
VDDCA + VDDQ
50
50
50
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12
Unit
mA
μA
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© 2014 Micron Technology, Inc. All rights reserved.
2Gb: x16, x32, x64 Automotive LPDDR2 SDRAM
IDD Specifications
Table 6: 64 Meg x 32 IDD Specifications (Continued)
VDD2, VDDQ, VDDCA = 1.14–1.30V; VDD1 = 1.70–1.95V
Speed Grade
Parameter
Supply
-18
-25
-3
VDD1
600
600
600
IDD2PS2
VDD2
800
800
800
IDD2PS,in
VDDCA + VDDQ
50
50
50
IDD2N1
VDD1
2
2
2
IDD2N2
VDD2
30
30
30
IDD2N,in
VDDCA + VDDQ
7
6
6
IDD2NS1
VDD1
1.7
1.7
1.7
IDD2NS2
VDD2
27
27
27
IDD2NS,in
VDDCA + VDDQ
6
6
6
IDD3P1
VDD1
1200
1200
1200
μA
IDD3P2
VDD2
8
8
8
mA
IDD3P,in
VDDCA + VDDQ
150
150
150
μA
IDD3PS1
VDD1
1200
1200
1200
μA
IDD2PS1
Unit
μA
mA
mA
mA
IDD3PS2
VDD2
8
8
8
mA
IDD3PS,in
VDDCA + VDDQ
150
150
150
μA
IDD3N1
VDD1
2.5
2.5
2.5
mA
IDD3N2
VDD2
30
30
30
IDD3N,in
VDDCA + VDDQ
7
6
6
IDD3NS1
VDD1
2
2
2
IDD3NS2
VDD2
27
27
27
IDD3NS,in
VDDCA + VDDQ
6
6
6
IDD4R1
VDD1
3
3
3
IDD4R2
VDD2
220
194
178
IDD4R,in
VDDCA
6
6
6
IDD4W1
VDD1
10
10
10
IDD4W2
VDD2
190
185
170
IDD4W,in
VDDCA + VDDQ
25
25
25
IDD51
VDD1
40
40
40
IDD52
VDD2
150
150
150
IDD5,in
VDDCA + VDDQ
8
6
6
IDD5PB1
VDD1
5
5
5
IDD5PB2
VDD2
50
50
50
IDD5PB,in
VDDCA + VDDQ
8
8
8
IDD5PBET1
VDD1
10.5
10.5
10.5
IDD5PBET2
VDD2
80
80
80
IDD5PB,ETin
VDDCA + VDDQ
8
8
8
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13
mA
mA
mA
mA
mA
mA
mA
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2Gb: x16, x32, x64 Automotive LPDDR2 SDRAM
IDD Specifications
Table 6: 64 Meg x 32 IDD Specifications (Continued)
VDD2, VDDQ, VDDCA = 1.14–1.30V; VDD1 = 1.70–1.95V
Speed Grade
Parameter
IDDAB1
Supply
-18
-25
-3
VDD1
5
5
5
IDD5AB2
VDD2
50
50
50
IDD5AB,in
VDDCA + VDDQ
8
8
8
IDDABET1
VDD1
10.5
10.5
10.5
IDD5ABET2
VDD2
80
80
80
IDD5AB,ETin
Unit
mA
mA
VDDCA + VDDQ
8
8
8
IDD61
VDD1
1000
1000
1000
IDD62
VDD2
3200
3200
3200
IDD6,in
VDDCA + VDDQ
50
50
50
IDD6ET1
VDD1
3100
3100
3100
μA
IDD6ET2
VDD2
13.7
13.7
13.7
mA
IDD6,ETin
VDDCA + VDDQ
90
90
90
µA
VDD1
25
25
25
IDD81
IDD82
VDD2
100
100
100
IDD8,in
VDDCA + VDDQ
100
100
100
μA
μA
Table 7: IDD6 Partial-Array Self Refresh Current
VDD2, VDDQ, VDDCA = 1.14–1.30V; VDD1 = 1.70–1.95V
PASR
Supply
Value (–30˚C to +85˚C)
Full array
1/2 array
1/4 array
1/8 array
Value (+85˚C to +105˚C)
Unit
VDD1
1000
3100
μA
VDD2
3.2
13.7
mA
µA
VDDi
50
90
VDD1
950
2200
VDD2
2700
7300
VDDi
50
90
VDD1
900
1600
VDD2
2400
4300
VDDi
50
90
VDD1
850
1300
VDD2
2000
2800
VDDi
50
90
Note:
PDF: 09005aef8597bf6f
2gb_automotive_lpddr2_u89n.pdf - Rev. D 4/15 EN
1. LPDDR2-S4 SDRAM devices support both bank masking and segment masking. IDD6 PASR
currents are measured using bank masking only.
14
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2Gb: x16, x32, x64 Automotive LPDDR2 SDRAM
IDD Specifications
Figure 2: VDD1Typical Self Refresh Current vs. Temperature
2000
1800
IDD6 1/8 VDD1 (µa)
1600
IDD6 1/4 VDD1 (µa)
1400
IDD6 1/2 VDD1 (µa)
1200
IDD6 Full VDD1 (µa)
1000
800
600
400
200
0
-40
-20
0
25
35
45
65
80
85
95
110
65
80
85
95
110
Figure 3: VDD2 Typical Self Refresh Current vs. Temperature
10000
9000
IDD6 1/8 VDD2 (µa)
8000
IDD6 1/4 VDD2 (µa)
IDD6 1/2 VDD2 (µa)
7000
IDD6 Full VDD2 (µa)
6000
5000
4000
3000
2000
1000
0
-40
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-20
0
25
15
35
45
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2Gb: x16, x32, x64 Automotive LPDDR2 SDRAM
Package Block Diagrams
Package Block Diagrams
Figure 4: Single Rank, Single Channel Package Block Diagram
VDD1 VDD2 VDDQ VDDCA VSS
VREFCA
VREFDQ
ZQ
CS0#
RZQ
CKE0
CK
CK#
DM
LPDDR2
Die 0
CA[9:0]
DQ, DQS
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2Gb: x16, x32, x64 Automotive LPDDR2 SDRAM
Package Block Diagrams
Figure 5: Single Rank, Dual Channel Package Block Diagram
VDD1 VDD2 VDDQ VDDCA VSS
VREFCA(b)
VREFDQ(b)
ZQ0
CS0#
RZQ
CKE0
CK#
CK
DM
LPDDR2
Die 0
Channel B
CA[9:0]
DQ[31:0], DQS
DQ[31:0], DQS
CA[9:0]
DM
CK
CK#
LPDDR2
Die 1
Channel A
CKE0
CS0#
ZQ0
RZQ
VREFCA(a)
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VREFDQ(a)
17
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2Gb: x16, x32, x64 Automotive LPDDR2 SDRAM
Package Dimensions
Package Dimensions
Figure 6: 134-Ball FBGA – 10mm x 11.5mm Single-Die (Package Code TK)
Seating plane
A
134X Ø0.36
Dimensions apply
to solder balls postreflow on Ø0.30 SMD
ball pads.
0.08 A
Ball A1 ID
(covered by SR)
Ball A1 ID
10 9 8 7 6 5 4 3 2 1
A
B
C
D
E
F
G
H
J
K
L
M
N
P
R
T
U
11.5 ±0.1
10.4 CTR
0.65 TYP
0.6 ±0.1
0.65 TYP
5.85 CTR
0.22 MIN
10 ±0.1
Note:
PDF: 09005aef8597bf6f
2gb_automotive_lpddr2_u89n.pdf - Rev. D 4/15 EN
1. All dimensions are in millimeters.
18
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2Gb: x16, x32, x64 Automotive LPDDR2 SDRAM
Package Dimensions
Figure 7: 168-Ball FBGA – 12mm x 12mm Single-Die (Package Code LF)
Seating plane
A
168X Ø0.355
Dimensions apply
to solder balls postreflow on Ø0.28 SMD
ball pads.
0.08 A
Ball A1 ID
23
22
Ball A1 ID
20 18 16 14 12 10 8
6 4
2
21 19 17 15 13 11 9
7
5
3
1
A
B
C
D
E
F
G
H
J
K
L
M
N
P
R
T
U
V
W
Y
AA
AB
AC
11 CTR
12 ±0.1
0.65 ±0.1
0.5 TYP
0.5 TYP
11 CTR
0.24 MIN
12 ±0.1
Note:
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2gb_automotive_lpddr2_u89n.pdf - Rev. D 4/15 EN
1. All dimensions are in millimeters.
19
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2Gb: x16, x32, x64 Automotive LPDDR2 SDRAM
Package Dimensions
Figure 8: 216-Ball FBGA – 12mm x 12mm (Package Codes LL)
Seating plane
A
216X Ø0.27
Dimensions
apply to solder
balls post-reflow
on Ø0.24 SMD
ball pads.
0.08 A
Ball A1 ID
(covered by SR)
Ball A1 ID
28 26 24 22 20 18 16 14 12 10 8 6 4 2
29 27 25 23 21 19 17 15 13 11 9 7 5 3 1
A
B
C
D
E
F
G
H
J
K
L
M
N
P
R
T
U
V
W
Y
AA
AB
AC
AD
AE
AF
AG
AH
AJ
11.2 CTR
12 ±0.1
0.4 TYP
0.7 ±0.1
0.4 TYP
11.2 CTR
0.13 MIN
12 ±0.1
Note:
PDF: 09005aef8597bf6f
2gb_automotive_lpddr2_u89n.pdf - Rev. D 4/15 EN
1. All dimensions are in millimeters.
20
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2Gb: x16, x32, x64 Automotive LPDDR2 SDRAM
Ball Assignments and Descriptions
Ball Assignments and Descriptions
Figure 9: 134-Ball FBGA (x32)
2
A
DNU
DNU
B
DNU
NC
NC
C
V DD1
V SS
ZQ1
D
V SS
V DD2
E
V SSCA
4
6
5
7
9
10
DNU
DNU
A
DQ31 DQ29 DQ26
DNU
B
V DDQ DQ25
V DDQ
C
ZQ0
V DDQ DQ30 DQ27 DQS3 DQS3# V SSQ
D
CA9
CA8
DQ28 DQ24
V SSQ
E
F V DDCA CA6
CA7
V SSQ DQ11 DQ13 DQ14 DQ12 V DDQ
F
G
V DD2
V DD2 V DD1
V SS
CA5 V REFCA
V SSQ
8
V SSQ
DM3 DQ15 V DDQ
DQS1# DQS1 DQ10 DQ9
DQ8
V SSQ
G
H V DDCA
V SS
CK#
DM1 V DDQ
J
V SSCA
NC
CK
V SSQ V DDQ
K
CKE0 CKE1
RFU
DM0 V DDQ
L
CS0#
CS1#
RFU
DQS0# DQS0
DQ5
DQ6
DQ7
V SSQ
L
M
CA4
CA3
CA2
V SSQ
DQ4
DQ2
DQ1
DQ3
V DDQ
M
CA1
DQ19 DQ23
DM2
DQ0
V DDQ
V SSQ
N
V DDQ DQ17 DQ20 DQS2 DQS2# V SSQ
P
N
PDF: 09005aef8597bf6f
2gb_automotive_lpddr2_u89n.pdf - Rev. D 4/15 EN
3
1
V SSCA V DDCA
P
V SS
VDD2
CA0
R
V DD1
V SS
NC
T
DNU
NC
NC
U
DNU
DNU
1
2
3
V SS
V SSQ
V DD2 V DD1
4
6
5
21
H
V DD2
V SS
J
V REFDQ
K
V SSQ
V DDQ
R
DQ16 DQ18 DQ21
DNU
T
DNU
DNU
U
9
10
VDDQ DQ22
7
8
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2Gb: x16, x32, x64 Automotive LPDDR2 SDRAM
Ball Assignments and Descriptions
Figure 10: 168-Ball FBGA – 12mm x 12mm
1
2
3
4
5
A
DNU
DNU
NC
NC
NC
B
DNU
DNU
V DD1
NC
NC
C
V SS
V DD2
D
NC
E
NC
F
6
7
21
22
23
V SS
DNU
DNU
A
V DD2 DNU
DNU
B
V SSQ
C
NC
V DDQ DQ14
D
NC
DQ12 DQ13
E
DQ11
V SSQ
F
(NC) 2 NC
NC
NC
8
9
10
11
12
V SSQ
13
14
15
16
17
18
19
NC
(NC) 2 NC
V DD1
NC
NC
V DD2 DQ31 V DDQ DQ28 DQ27 V DDQ DQ24 DQS3 V DDQ
V SS
DQ30 DQ29
V SSQ DQ26 DQ25
20
V SSQ DQS#3 V DD1
DM3
DQ15
(NC) 2 NC
G
NC
NC
V DDQ DQ10
G
H
NC
NC
DQ8
DQ9
H
(NC) 2 NC
DQS1
V SSQ
J
J
K
NC
NC
V DDQ DQS#1
K
L
NC
NC
V DD2
DM1
L
M
NC
V SS
VREFDQ
V SS
M
N
NC
V DD1
V DD1
DM0
N
P
ZQ
VREFCA
DQS#0 V SSQ
P
R
V SS
V DD2
V DDQ DQS0
R
T
CA9
CA8
DQ6
DQ7
T
U
CA7 V DDCA
DQ5
V SSQ
U
V DDQ
DQ4
V
V
V SSCA
CA6
W
CA5 V DDCA
DQ2
DQ3
W
Y
CK#
CK
DQ1
V SSQ
Y
AA
V SS
V DD2
V DDQ
DQ0
AA
AB DNU
DNU
CS0# CS1# V DD1
CA1
VSSCA CA3
V DD2 DNU
DNU
AB
AC DNU
DNU
CKE0 CKE1
V SS
CA0
CA2 V DDCA V SS 1
AC
5
6
1
2
3
4
7
8
CA4
9
V DD2
V SS
DQ16 V DDQ DQ18 DQ20 V DDQ DQ22 DQS2 V DDQ
(NC) 2
NC
V SSQ DQ17 DQ19
10
11
12
13
14
V SSQ DQ21 DQ23
15
16
17
DM2
V SSQ DQS#2 V DD1
18
19
20
V SS
DNU
DNU
21
22
23
Top View (ball down)
LPDDR2
Notes:
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Supply
Ground
1. Ball AC9 may be VSS or left unconnected.
2. Balls labeled NC = no connect; however, they can be connected together internally.
22
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2Gb: x16, x32, x64 Automotive LPDDR2 SDRAM
Ball Assignments and Descriptions
Figure 11: 216-Ball 2-Channel FBGA – 12mm x 12mm
28
29
A DNU V SS V DD2 DQ30 DQ29 V SSQ DQ26 DQ25 V SSQ DQS#3 V SSQ DQ14 DQ13 V SS V DD1 V DD2 DQ11 DQ10 DQ9 DQS1 DM1 V DDQ DQS0 DQ7 DQ6 DQ4 DQ3
V SS
DNU
A
B V SSQ
NC
V SSQ
B
C V DD1 DQ16
V DD1 V DD2
C
D DQ17 V DDQ
DQ1 V DDQ
D
E DQ18 DQ19
V SSQ DQ0
E
F
DM2 V DDQ
F
G DQ21 V DDQ
DQS2 DQS#2
G
H DQ22 DQ23
V SSQ DQ23
H
J
V SSQ V DDQ
V DDQ DQ22
J
K DQS#2 DQS2
DQ20 DQ21
K
L
DM2 DQ0
DQ19 V SSQ
L
M DQ1 V SSQ
V DDQ DQ18
M
N DQ2 V DD1
DQ16 DQ17
N
P
V DD2 V DD1
P
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
NC DQ31 V DDQ DQ28 DQ27 V DDQ DQ24 V DDQ DQS3 DM3 DQ15 V DDQ V SSQ VREFDQ V DD2 DQ12 V DDQ DQ8 DQS#1 V SSQ DM0 DQS#0 V SSQ V DDQ DQ5 DQ2
V SSQ DQ20
V SS
V SS
R V DD1 VREFDQ
CA0
R
T V DD2 V DD2
V DDCA CA1
T
U V DDQ DQ3
V REFCA CA2
U
V DQ4 V SSQ
V SSCA CA3
V
W DQ6 DQ5
CA4 CS1#
W
Y V DDQ DQ7
CS0# CKE1
Y
AA DQS0 DQS#0
V SSCA CKE0
AA
V SS
AB DM0 V SSQ
CK#
AB
V DDCA CA5
AC
CK
AC V DDQ DM1
AD DQS# 1DQS1
CA7
AE DQ8 V SSQ
CA8 V DDCA
CA6
AD
AE
AF DQ9 V DDQ
V SSCA CA9
AF
AG DQ10 DQ11
V DD2
AG
ZQ
AH V SSQ V DD1 V DD2 DQ13 V SSQ DQ15 DM3 DQS3 V DDQ DQ26 DQ27 V DDQ DQ30 V SSQ V DD2 VREFCA CA9 VSSCA CA7 CA6 CK# VDDCA CKE0 CS0# CA3 CA2 CA1 V DD1 VSSCA AH
AJ DNU V SS DQ12 V DDQ DQ14 V DDQ V SSQ DQS#3 DQ24 DQ25 V SSQ DQ28 DQ29 DQ31 V DD1 V SS
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
ZQ
17
Top View (ball down)
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23
CA8 V DDCA CA5
18
19
20
CK
21
Channel A
V SSCA CKE1 CS1# CA4 V DDCA CA0
22
23
24
25
Channel B
26
27
Supply
V SS
DNU
28
29
AJ
Ground
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2Gb: x16, x32, x64 Automotive LPDDR2 SDRAM
Ball Assignments and Descriptions
Table 8: Ball/Pad Descriptions
Symbol
Type
Description
CA[9:0]
Input
Command/address inputs: Provide the command and address inputs according
to the command truth table.
CK, CK#
Input
Clock: CK and CK# are differential clock inputs. All CA inputs are sampled on
both rising and falling edges of CK. CS and CKE inputs are sampled at the rising
edge of CK. AC timings are referenced to clock.
CKE[1:0]
Input
Clock enable: CKE HIGH activates and CKE LOW deactivates the internal clock
signals, input buffers, and output drivers. Power-saving modes are entered and
exited via CKE transitions. CKE is considered part of the command code. CKE is
sampled at the rising edge of CK.
CS[1:0]#
Input
Chip select: CS# is considered part of the command code and is sampled at the
rising edge of CK.
DM[3:0]
Input
Input data mask: DM is an input mask signal for write data. Although DM balls
are input-only, the DM loading is designed to match that of DQ and DQS balls.
DM[3:0] is DM for each of the four data bytes, respectively.
DQ[31:0]
I/O
Data input/output: Bidirectional data bus.
DQS[3:0],
DQS[3:0]#
I/O
Data strobe: The data strobe is bidirectional (used for read and write data) and
complementary (DQS and DQS#). It is edge-aligned output with read data and
centered input with write data. DQS[3:0]/DQS[3:0]# is DQS for each of the four
data bytes, respectively.
VDDQ
Supply
DQ power supply: Isolated on the die for improved noise immunity.
VSSQ
Supply
DQ ground: Isolated on the die for improved noise immunity.
VDDCA
Supply
Command/address power supply: Command/address power supply.
VSSCA
Supply
Command/address ground: Isolated on the die for improved noise immunity.
VDD1
Supply
Core power: Supply 1.
VDD2
Supply
Core power: Supply 2.
VSS
Supply
Common ground
VREFCA, VREFDQ
Supply
Reference voltage: VREFCA is reference for command/address input buffers,
VREFDQ is reference for DQ input buffers.
ZQ
Reference
DNU
–
Do not use: Must be grounded or left floating.
NC
–
No connect: Not internally connected.
(NC)
–
No connect: Balls indicated as (NC) are no connects, however, they could be connected together internally.
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External impedance (240 ohm): This signal is used to calibrate the device output impedance.
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2Gb: x16, x32, x64 Automotive LPDDR2 SDRAM
Functional Description
Functional Description
Mobile LPDDR2 is a high-speed SDRAM internally configured as a 4- or 8-bank memory
device. LPDDR2 devices use a double data rate architecture on the command/address
(CA) bus to reduce the number of input pins in the system. The 10-bit CA bus is used to
transmit command, address, and bank information. Each command uses one clock cycle, during which command information is transferred on both the rising and falling
edges of the clock.
LPDDR2-S4 devices use a double data rate architecture on the DQ pins to achieve highspeed operation. The double data rate architecture is essentially a 4n prefetch architecture with an interface designed to transfer two data bits per DQ every clock cycle at the
I/O pins. A single read or write access for the LPDDR2-S4 effectively consists of a single
4n-bit-wide, one-clock-cycle data transfer at the internal SDRAM core and four corresponding n-bit-wide, one-half-clock-cycle data transfers at the I/O pins.
Read and write accesses 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 ACTIVATE command followed by a READ or
WRITE command. The address and BA bits registered coincident with the ACTIVATE
command are used to select the row and bank 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.
Figure 12: Functional Block Diagram
CS#
CA0
CA1
CA2
CA3
CA4
CA5
CA6
CA7
CA8
CA9
Control
logic
Command / Address
Multiplex and Decode
CKE
CK
CK#
Mode
registers
x
Refresh x
counter
Rowaddress
MUX
Bank 7
Bank 7
Bank 6
Bank 6
Bank 5
Bank 5
Bank 4
Bank 4
Bank 3
Bank 3
Bank 2
Bank 2
Bank 1
Bank 1
Bank 0
Bank 0
rowMemory array
address
latch
and
decoder
COL0
n
4n
Read
latch
n
MUX
n
n
Sense amplifier
3
Bank
control
logic
Column- y - 1
address
1
counter/
latch
I/O gating
DM mask logic
Column
decoder
DRVRS
DQ0–DQn-1
DQS
generator
DQS, DQS#
Input
registers
4
4
4n
3
n
DATA
4
8
WRITE
4
FIFO Mask
4
and
4n
drivers
n
CK, CK#
CK out
4n
CK in
Data
4
4
DQS, DQS#
4
4
RCVRS
n
n
n
n
n
n
n
n
DM
COL0
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2Gb: x16, x32, x64 Automotive LPDDR2 SDRAM
Power-Up
Power-Up
The following sequence must be used to power up the device. Unless specified otherwise, this procedure is mandatory (see Figure 13 (page 28)). Power-up and initialization by means other than those specified will result in undefined operation.
1. Voltage Ramp
While applying power (after Ta), CKE must be held LOW (≤0.2 × V DDCA), and all other
inputs must be between V ILmin and V IHmax. The device outputs remain at High-Z while
CKE is held LOW.
On or before the completion of the voltage ramp (Tb), CKE must be held LOW. DQ, DM,
DQS, and DQS# voltage levels must be between V SSQ and V DDQ during voltage ramp to
avoid latchup. CK, CK#, CS#, and CA input levels must be between V SSCA and V DDCA during voltage ramp to avoid latchup.
The following conditions apply for voltage ramp:
• Ta is the point when any power supply first reaches 300mV.
• Noted conditions apply between Ta and power-down (controlled or uncontrolled).
• Tb is the point at which all supply and reference voltages are within their defined operating ranges.
• Power ramp duration tINIT0 (Tb - Ta) must not exceed 20ms.
• For supply and reference voltage operating conditions, see the Recommended DC
Operating Conditions table.
• The voltage difference between any of V SS, V SSQ, and V SSCA pins must not exceed
100mV.
Voltage Ramp Completion
After Ta is reached:
•
•
•
•
VDD1 must be greater than V DD2 - 200mV
VDD1 and V DD2 must be greater than V DDCA - 200mV
VDD1 and V DD2 must be greater than V DDQ - 200mV
VREF must always be less than all other supply voltages
Beginning at Tb, CKE must remain LOW for at least tINIT1 = 100ns, after which CKE can
be asserted HIGH. The clock must be stable at least tINIT2 = 5 × tCK prior to the first
CKE LOW-to-HIGH transition (Tc). CKE, CS#, and CA inputs must observe setup and
hold requirements (tIS, tIH) with respect to the first rising clock edge (and to subsequent falling and rising edges).
If any MRRs are issued, the clock period must be within the range defined for tCKb
(18ns to 100ns). MRWs can be issued at normal clock frequencies as long as all AC timings are met. Some AC parameters (for example, tDQSCK) could have relaxed timings
(such as tDQSCKb) before the system is appropriately configured. While keeping CKE
HIGH, NOP commands must be issued for at least tINIT3 = 200µs (Td).
2. RESET Command
After tINIT3 is satisfied, the MRW RESET command must be issued (Td). An optional
PRECHARGE ALL command can be issued prior to the MRW RESET command.
Wait at least tINIT4 while keeping CKE asserted and issuing NOP commands.
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2Gb: x16, x32, x64 Automotive LPDDR2 SDRAM
Power-Up
3. MRRs and Device Auto Initialization (DAI) Polling
After tINIT4 is satisfied (Te), only MRR commands and power-down entry/exit commands are supported. After Te, CKE can go LOW in alignment with power-down entry
and exit specifications (see Power-Down (page 80)).
The MRR command can be used to poll the DAI bit, which indicates when device auto
initialization is complete; otherwise, the controller must wait a minimum of tINIT5, or
until the DAI bit is set, before proceeding.
Because the memory output buffers are not properly configured by Te, some AC parameters must use relaxed timing specifications before the system is appropriately configured.
After the DAI bit (MR0, DAI) is set to zero by the memory device (DAI complete), the
device is in the idle state (Tf ). DAI status can be determined by issuing the MRR command to MR0.
The device sets the DAI bit no later than tINIT5 after the RESET command. The controller must wait at least tINIT5 or until the DAI bit is set before proceeding.
4. ZQ Calibration
After tINIT5 (Tf), the MRW initialization calibration (ZQ calibration) command can be
issued to the memory (MR10).
This command is used to calibrate output impedance over process, voltage, and temperature. In systems where more than one Mobile LPDDR2 device exists on the same
bus, the controller must not overlap MRW ZQ calibration commands. The device is
ready for normal operation after tZQINIT.
5. Normal Operation
After (Tg), MRW commands must be used to properly configure the memory (output
buffer drive strength, latencies, etc.). Specifically, MR1, MR2, and MR3 must be set to
configure the memory for the target frequency and memory configuration.
After the initialization sequence is complete, the device is ready for any valid command.
After Tg, the clock frequency can be changed using the procedure described in Input
Clock Frequency Changes and Clock Stop with CKE HIGH (page 89).
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2Gb: x16, x32, x64 Automotive LPDDR2 SDRAM
Power-Off
Figure 13: Voltage Ramp and Initialization Sequence
Ta
Tb
tINIT2
Tc
Td
Te
Tf
Tg
CK/CK#
tINIT0
Supplies
tINIT1
tINIT3
CKE
tINIT4
tISCKE
CA
RESET
tINIT5
MRR
tZQINIT
MRW
ZQ_CAL
Valid
RTT
DQ
Note:
1. High-Z on the CA bus indicates valid NOP.
Table 9: Initialization Timing Parameters
Value
Parameter
Min
Max
Unit
tINIT0
–
20
ms
Maximum voltage ramp time
tINIT1
100
–
ns
Minimum CKE LOW time after completion of voltage ramp
tINIT2
5
–
tCK
Minimum stable clock before first CKE HIGH
tINIT3
200
–
μs
Minimum idle time after first CKE assertion
tINIT4
1
–
μs
Minimum idle time after RESET command
tINIT5
–
10
μs
Maximum duration of device auto initialization
tZQINIT
1
–
μs
ZQ initial calibration (S4 devices only)
tCKb
18
100
ns
Clock cycle time during boot
Note:
Comment
1. The tINIT0 maximum specification is not a tested limit and should be used as a general
guideline. For voltage ramp times exceeding tINIT0 MAX, please contact the factory.
Initialization After RESET (Without Voltage Ramp)
If the RESET command is issued before or after the power-up initialization sequence,
the reinitialization procedure must begin at Td.
Power-Off
While powering off, CKE must be held LOW (≤0.2 × V DDCA); all other inputs must be between V ILmin and V IHmax. The device outputs remain at High-Z while CKE is held LOW.
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2Gb: x16, x32, x64 Automotive LPDDR2 SDRAM
Mode Register Definition
DQ, DM, DQS, and DQS# voltage levels must be between V SSQ and V DDQ during the
power-off sequence to avoid latchup. CK, CK#, CS#, and CA input levels must be between V SSCA and V DDCA during the power-off sequence to avoid latchup.
Tx is the point where any power supply drops below the minimum value specified in
the Recommended DC Operating Conditions table.
Tz is the point where all power supplies are below 300mV. After Tz, the device is powered off.
Required Power Supply Conditions Between Tx and Tz:
•
•
•
•
VDD1 must be greater than V DD2 - 200mV
VDD1 must be greater than V DDCA - 200mV
VDD1 must be greater than V DDQ - 200mV
VREF must always be less than all other supply voltages
The voltage difference between V SS, V SSQ, and V SSCA must not exceed 100mV.
For supply and reference voltage operating conditions, see Recommended DC Operating Conditions table.
Uncontrolled Power-Off
When an uncontrolled power-off occurs, the following conditions must be met:
• At Tx, when the power supply drops below the minimum values specified in the Recommended DC Operating Conditions table, all power supplies must be turned off and
all power-supply current capacity must be at zero, except for any static charge remaining in the system.
• After Tz (the point at which all power supplies first reach 300mV), the device must
power off. The time between Tx and Tz must not exceed tPOFF. During this period, the
relative voltage between power supplies is uncontrolled. V DD1 and V DD2 must decrease with a slope lower than 0.5 V/µs between Tx and Tz.
An uncontrolled power-off sequence can occur a maximum of 400 times over the life of
the device.
Table 10: Power-Off Timing
Parameter
Maximum power-off ramp time
Symbol
Min
Max
Unit
tPOFF
–
2
sec
Mode Register Definition
LPDDR2 devices contain a set of mode registers used for programming device operating
parameters, reading device information and status, and for initiating special operations
such as DQ calibration, ZQ calibration, and device reset.
Mode Register Assignments and Definitions
The MRR command is used to read from a register. The MRW command is used to write
to a register. An “R” in the access column of the mode register assignment table indicates read-only; a “W” indicates write-only; “R/W” indicates read or write capable or
enabled.
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2Gb: x16, x32, x64 Automotive LPDDR2 SDRAM
Mode Register Definition
Table 11: Mode Register Assignments
Notes 1–5 apply to all parameters and conditions
MR#
MA[7:0]
Function
Access
OP7
OP6
OP5
OP4
OP3
OP1
OP0
DNVI
DI
DAI
Link
0
00h
Device info
R
RFU
1
01h
Device feature 1
W
nWR (for AP)
2
02h
Device feature 2
W
3
03h
I/O config-1
W
4
04h
SDRAM refresh
rate
R
5
05h
Basic config-1
R
LPDDR2 Manufacturer ID
go to MR5
6
06h
Basic config-2
R
Revision ID1
go to MR6
7
07h
Basic config-3
R
Revision ID2
go to MR7
8
08h
Basic config-4
R
9
09h
Test mode
W
Vendor-specific test mode
TUF
RZQI
OP2
WC
BT
go to MR0
BL
go to MR1
RFU
RL and WL
go to MR2
RFU
DS
go to MR3
RFU
I/O width
Refresh rate
Density
Type
go to MR4
go to MR8
go to MR9
10
0Ah
I/O calibration
W
Calibration code
go to MR10
11–15
0Bh ≈ 0Fh
Reserved
–
RFU
go to MR11
16
10h
PASR_Bank
W
Bank mask
go to MR16
17
11h
PASR_Seg
W
Segment mask
go to MR17
18–19
12h–13h
Reserved
–
RFU
go to MR18
20–31
14h–1Fh
32
20h
DQ calibration
pattern A
33–39
21h–27h
Do not use
40
28h
DQ calibration
pattern B
41–47
29h–2Fh
Do not use
48–62
30h–3Eh
Reserved
–
RFU
go to MR48
63
3Fh
RESET
W
X
go to MR63
64–126
40h–7Eh
Reserved
–
RFU
go to MR64
127
7Fh
Do not use
128–190
80h–BEh
191
BFh
192–254
C0h–FEh
255
FFh
Reserved for NVM
R
MR20–MR30
See Table 48 (page 76).
go to MR33
R
See Table 48 (page 76).
go to MR127
RVU
Do not use
go to MR128
go to MR191
Reserved for vendor use
RVU
Do not use
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go to MR40
go to MR41
Reserved for vendor use
Notes:
go to MR32
go to MR192
go to MR255
1. RFU bits must be set to 0 during MRW.
2. RFU bits must be read as 0 during MRR.
3. For READs to a write-only or RFU register, DQS will be toggled and undefined data is
returned.
4. RFU mode registers must not be written.
5. WRITEs to read-only registers must have no impact on the functionality of the device.
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2Gb: x16, x32, x64 Automotive LPDDR2 SDRAM
Mode Register Definition
Table 12: MR0 Device Information (MA[7:0] = 00h)
OP7
OP6
OP5
OP4
RFU
OP3
RZQI
OP2
OP1
OP0
DNVI
DI
DAI
Table 13: MR0 Op-Code Bit Definitions
Notes 1–4 apply to all parameters and conditions
Register Information
Tag
Type
Device auto initialization
status
Device information
DAI
Read-only
OP
Definition
OP0
0b: DAI complete
1b: DAI in progress
DI
Read-only
OP1
0b
1b: NVM
Data not valid information
DNVI
Read-only
OP2
Built-in self test for RZQ
information
RZQI
Read-only
OP[4:3]
0b: DNVI not supported
00b: RZQ self test not supported
01b: ZQ pin might be connected to VDDCA or left floating
10b: ZQ pin might be shorted to ground
11b: ZQ pin self test complete; no error condition detected
Notes:
1. If RZQI is supported, it will be set upon completion of the MRW ZQ initialization calibration.
2. If ZQ is connected to VDDCA to set default calibration, OP[4:3] must be set to 01. If ZQ is
not connected to VDDCA, either OP[4:3] = 01 or OP[4:3] = 10 could indicate a ZQ-pin assembly error. It is recommended that the assembly error be corrected.
3. In the case of a possible assembly error (either OP[4:3] = 01 or OP[4:3] = 10, as defined
above), the device will default to factory trim settings for RON and will ignore ZQ calibration commands. In either case, the system might not function as intended.
4. If a ZQ self test returns a value of 11b, this indicates that the device has detected a resistor connection to the ZQ pin. Note that this result cannot be used to validate the ZQ
resistor value, nor does it indicate that the ZQ resistor tolerance meets the specified limits (240 ohms ±1%).
Table 14: MR1 Device Feature 1 (MA[7:0] = 01h)
OP7
OP6
OP5
nWR (for AP)
OP4
OP3
WC
BT
OP2
OP1
OP0
BL
Table 15: MR1 Op-Code Bit Definitions
Feature
BL = burst length
Type
OP
Write-only
OP[2:0]
Definition
Notes
010b: BL4 (default)
011b: BL8
100b: BL16
All others: Reserved
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2Gb: x16, x32, x64 Automotive LPDDR2 SDRAM
Mode Register Definition
Table 15: MR1 Op-Code Bit Definitions (Continued)
Feature
BT = burst type
Type
OP
Definition
Write-only
OP3
0b: Sequential (default)
Notes
1b: Interleaved
WC = wrap control
Write-only
OP4
0b: Wrap (default)
nWR = number of tWR clock
cycles
Write-only
OP[7:5]
1b: No wrap
001b: nWR = 3 (default)
1
010b: nWR = 4
011b: nWR = 5
100b: nWR = 6
101b: nWR = 7
110b: nWR = 8
All others: Reserved
Note:
1. The programmed value in nWR register is the number of clock cycles that determines
when to start internal precharge operation for a WRITE burst with AP enabled. It is determined by RU (tWR/tCK).
Table 16: Burst Sequence by Burst Length (BL), Burst Type (BT), and Wrap Control (WC)
Notes 1–5 apply to all parameters and conditions
Burst Cycle Number and Burst Address Sequence
BL
BT
C3
C2
C1
C0
WC
1
2
3
4
4
Any
X
X
0b
0b
Wrap
0
1
2
3
X
X
1b
0b
2
3
0
1
Any
X
X
X
0b
No
wrap
y
Seq
X
0b
0b
0b
Wrap
0
1
2
X
0b
1b
0b
2
3
X
1b
0b
0b
4
5
X
1b
1b
0b
6
X
0b
0b
0b
X
0b
1b
X
1b
0b
X
1b
X
X
8
Int
Any
5
6
7
8
3
4
5
6
7
4
5
6
7
0
1
6
7
0
1
2
3
7
0
1
2
3
4
5
0
1
2
3
4
5
6
7
0b
2
3
0
1
6
7
4
5
0b
4
5
6
7
0
1
2
3
1b
0b
6
7
4
5
2
3
0
1
X
0b
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9
10
11
12
13
14
15
16
y+ y+ y+
1
2
3
No
wrap
Illegal (not supported)
32
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Mode Register Definition
Table 16: Burst Sequence by Burst Length (BL), Burst Type (BT), and Wrap Control (WC) (Continued)
Notes 1–5 apply to all parameters and conditions
Burst Cycle Number and Burst Address Sequence
BL
BT
C3
C2
C1
C0
WC
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
16
Seq
0b
0b
0b
0b
Wrap
0
1
2
3
4
5
6
7
8
9
A
B
C
D
E
F
0b
0b
1b
0b
2
3
4
5
6
7
8
9
A
B
C
D
E
F
0
1
0b
1b
0b
0b
4
5
6
7
8
9
A
B
C
D
E
F
0
1
2
3
0b
1b
1b
0b
6
7
8
9
A
B
C
D
E
F
0
1
2
3
4
5
1b
0b
0b
0b
8
9
A
B
C
D
E
F
0
1
2
3
4
5
6
7
1b
0b
1b
0b
A
B
C
D
E
F
0
1
2
3
4
5
6
7
8
9
1b
1b
0b
0b
C
D
E
F
0
1
2
3
4
5
6
7
8
9
A
B
1b
1b
1b
0b
E
F
0
1
2
3
4
5
6
7
8
9
A
B
C
D
Int
X
X
X
0b
Any
X
X
X
0b
Notes:
1.
2.
3.
4.
5.
Illegal (not supported)
No
wrap
Illegal (not supported)
C0 input is not present on CA bus. It is implied zero.
For BL = 4, the burst address represents C[1:0].
For BL = 8, the burst address represents C[2:0].
For BL = 16, the burst address represents C[3:0].
For no-wrap, BL4, the burst must not cross the page boundary or the sub-page boundary. The variable y can start at any address with C0 equal to 0, but must not start at any
address shown in the following table.
Table 17: No-Wrap Restrictions
Width
64Mb
128Mb/256Mb
512Mb/1Gb/2Gb
4Gb/8Gb
Cannot cross full-page boundary
x16
FE, FF, 00, 01
1FE, 1FF, 000, 001
3FE, 3FF, 000, 001
7FE, 7FF, 000, 001
x32
7E, 7F, 00, 01
FE, FF, 00, 01
1FE, 1FF, 000, 001
3FE, 3FF, 000, 001
x16
7E, 7F, 80, 81
0FE, 0FF, 100, 101
1FE, 1FF, 200, 201
3FE, 3FF, 400, 401
x32
None
None
None
None
Cannot cross sub-page boundary
Note:
1. No-wrap BL = 4 data orders shown are prohibited.
Table 18: MR2 Device Feature 2 (MA[7:0] = 02h)
OP7
OP6
OP5
RFU
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OP4
OP3
OP2
OP1
OP0
RL and WL
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Mode Register Definition
Table 19: MR2 Op-Code Bit Definitions
Feature
RL and
WL
Type
OP
Write-only
OP[3:0]
Definition
0001b: RL3/WL1 (default)
0010b: RL4/WL2
0011b: RL5/WL2
0100b: RL6/WL3
0101b: RL7/WL4
0110b: RL8/WL4
All others: Reserved
Table 20: MR3 I/O Configuration 1 (MA[7:0] = 03h)
OP7
OP6
OP5
OP4
OP3
OP2
RFU
OP1
OP0
OP1
OP0
DS
Table 21: MR3 Op-Code Bit Definitions
Feature
DS
Type
OP
Write-only
OP[3:0]
Definition
0000b: Reserved
0001b: 34.3 ohm typical
0010b: 40 ohm typical (default)
0011b: 48 ohm typical
0100b: 60 ohm typical
0101b: Reserved
0110b: 80 ohm typical
0111b: 120 ohm typical
All others: Reserved
Table 22: MR4 Device Temperature (MA[7:0] = 04h)
OP7
TUF
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OP6
OP5
OP4
RFU
34
OP3
OP2
SDRAM refresh rate
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2Gb: x16, x32, x64 Automotive LPDDR2 SDRAM
Mode Register Definition
Table 23: MR4 Op-Code Bit Definitions
Notes 1–8 apply to all parameters and conditions
Feature
Type
OP
Definition
SDRAM refresh
rate
Read-only
OP[2:0]
000b: SDRAM low temperature operating limit exceeded
001b: 4 × tREFI, 4 × tREFIpb, 4 × tREFW
010b: 2 × tREFI, 2 × tREFIpb, 2 × tREFW
011b: 1 × tREFI, 1 × tREFIpb, 1 × tREFW (≤85˚C)
100b: Reserved
101b: 0.25 × tREFI, 0.25 × tREFIpb, 0.25 × tREFW, do not derate SDRAM AC
timing
110b: 0.25 × tREFI, 0.25 × tREFIpb, 0.25 × tREFW, derate SDRAM AC timing
111b: SDRAM high temperature operating limit exceeded
Temperature update flag (TUF)
Read-only
OP7
0b: OP[2:0] value has not changed since last read of MR4
1b: OP[2:0] value has changed since last read of MR4
Notes:
1.
2.
3.
4.
5.
6.
A MODE REGISTER READ from MR4 will reset OP7 to 0.
OP7 is reset to 0 at power-up.
If OP2 = 1, the device temperature is greater than 85˚C.
OP7 is set to 1 if OP[2:0] has changed at any time since the last MR4 read.
The device might not operate properly when OP[2:0] = 000b or 111b.
For specified operating temperature range and maximum operating temperature, refer
to the Operating Temperature Range table.
7. LPDDR2 devices must be derated by adding 1.875ns to the following core timing parameters: tRCD, tRC, tRAS, tRP, and tRRD. The tDQSCK parameter must be derated as specified in AC Timing. Prevailing clock frequency specifications and related setup and hold
timings remain unchanged.
8. The recommended frequency for reading MR4 is provided in Temperature Sensor
(page 73).
9. While the AT grade product is guaranteed to operate from TCASE –40°C to 105°C, the
temperature sensor accuracy relative to this is not guaranteed. The temperature sensor
embedded in the LPDDR2 device is not an accurate reflection of the DRAM TCASE operating temperature. Sampling of the sensor has shown up to a ±7°C variance from actual
TCASE.
Table 24: MR5 Basic Configuration 1 (MA[7:0] = 05h)
OP7
OP6
OP5
OP4
OP3
OP2
OP1
OP0
LPDDR2 Manufacturer ID
Table 25: MR5 Op-Code Bit Definitions
Feature
Manufacturer ID
Type
OP
Read-only
OP[7:0]
Definition
1111 1111b: Micron
All others: Reserved
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Mode Register Definition
Table 26: MR6 Basic Configuration 2 (MA[7:0] = 06h)
OP7
OP6
OP5
OP4
OP3
OP2
OP1
OP0
OP1
OP0
Revision ID1
Note:
1. MR6 is vendor-specific.
Table 27: MR6 Op-Code Bit Definitions
Feature
Revision ID1
Type
OP
Read-only
OP[7:0]
Definition
0000 0000b: Version A
Table 28: MR7 Basic Configuration 3 (MA[7:0] = 07h)
OP7
OP6
OP5
OP4
OP3
OP2
Revision ID2
Table 29: MR7 Op-Code Bit Definitions
Feature
Revision ID2
Note:
Type
OP
Read-only
OP[7:0]
Definition
0000 0000b: Version A
1. MR7 is vendor-specific.
Table 30: MR8 Basic Configuration 4 (MA[7:0] = 08h)
OP7
OP6
OP5
I/O width
OP4
OP3
OP2
Density
OP1
OP0
Type
Table 31: MR8 Op-Code Bit Definitions
Feature
Type
Type
OP
Read-only
OP[1:0]
Definition
00b
01b
10b: NVM
11b: Reserved
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2Gb: x16, x32, x64 Automotive LPDDR2 SDRAM
Mode Register Definition
Table 31: MR8 Op-Code Bit Definitions (Continued)
Feature
Type
OP
Density
Read-only
OP[5:2]
Definition
0000b: 64Mb
0001b: 128Mb
0010b: 256Mb
0011b: 512Mb
0100b: 1Gb
0101b: 2Gb
0110b: 4Gb
0111b: 8Gb
1000b: 16Gb
1001b: 32Gb
All others: Reserved
I/O width
Read-only
OP[7:6]
00b: x32
01b: x16
10b: x8
11b: not used
Table 32: MR9 Test Mode (MA[7:0] = 09h)
OP7
OP6
OP5
OP4
OP3
OP2
OP1
OP0
Vendor-specific test mode
Table 33: MR10 Calibration (MA[7:0] = 0Ah)
OP7
OP6
OP5
S4
OP4
OP3
OP2
OP1
OP0
Calibration code
Table 34: MR10 Op-Code Bit Definitions
Notes 1–4 apply to all parameters and conditions
Feature
Type
OP
Definition
Calibration code
Write-only
OP[7:0]
0xFF: Calibration command after initialization
0xAB: Long calibration
0x56: Short calibration
0xC3: ZQRESET
All others: Reserved
Notes:
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1.
2.
3.
4.
Host processor must not write MR10 with reserved values.
The device ignores calibration commands when a reserved value is written into MR10.
See AC timing table for the calibration latency.
If ZQ is connected to VSSCA through RZQ, either the ZQ calibration function (see MRW ZQ
Calibration Commands (page 78)) or default calibration (through the ZQRESET command) is supported. If ZQ is connected to VDDCA, the device operates with default cali-
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Mode Register Definition
bration, and ZQ calibration commands are ignored. In both cases, the ZQ connection
must not change after power is supplied to the device.
Table 35: MR[11:15] Reserved (MA[7:0] = 0Bh–0Fh)
OP7
OP6
OP5
OP4
OP3
OP2
OP1
OP0
OP2
OP1
OP0
Reserved
Table 36: MR16 PASR Bank Mask (MA[7:0] = 010h)
OP7
OP6
OP5
OP4
OP3
Bank mask (4-bank or 8-bank)
Table 37: MR16 Op-Code Bit Definitions
Feature
Bank[7:0] mask
Type
OP
Write-only
OP[7:0]
Definition
0b: refresh enable to the bank = unmasked (default)
1b: refresh blocked = masked
Note:
1. For 4-bank devices, only OP[3:0] are used.
Table 38: MR17 PASR Segment Mask (MA[7:0] = 011h)
OP7
OP6
OP5
OP4
OP3
OP2
OP1
OP0
Segment mask
Note:
1. This table applies for 1Gb to 8Gb devices only.
Table 39: MR17 PASR Segment Mask Definitions
Feature
Segment[7:0] mask
Type
OP
Write-only
OP[7:0]
Definition
0b: refresh enable to the segment: = unmasked (default)
1b: refresh blocked: = masked
Table 40: MR17 PASR Row Address Ranges in Masked Segments
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1Gb
2Gb, 4Gb
8Gb
R[12:10]
R[13:11]
R[14:12]
Segment
OP
Segment Mask
0
0
XXXXXXX1
000b
1
1
XXXXXX1X
001b
2
2
XXXXX1XX
010b
3
3
XXXX1XXX
011b
4
4
XXX1XXXX
100b
5
5
XX1XXXXX
101b
6
6
X1XXXXXX
110b
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Mode Register Definition
Table 40: MR17 PASR Row Address Ranges in Masked Segments (Continued)
Note:
Segment
OP
Segment Mask
7
7
1XXXXXXX
1Gb
2Gb, 4Gb
8Gb
R[12:10]
R[13:11]
R[14:12]
111b
1. X is “Don’t Care” for the designated segment.
Table 41: Reserved Mode Registers
Mode Register
MA
Address
Restriction
MA[7:0]
12h–13h
RFU
MR[20:31]
14h–1Fh
NVM1
MR[33:39]
21h–27h
DNU1
MR[41:47]
29h–2Fh
MR[48:62]
30h–3Eh
RFU
MR[64:126]
40h–7Eh
RFU
MR127
7Fh
DNU
MR[128:190]
80h–BEh
RVU1
MR191
BFh
DNU
MR[192:254]
C0h–FEh
RVU
MR255
FFh
DNU
MR[18:19]
Note:
OP7
OP6
OP5
OP4
OP3
OP2
OP1
OP0
Reserved
1. NVM = nonvolatile memory use only; DNU = Do not use; RVU = Reserved for vendor use.
Table 42: MR63 RESET (MA[7:0] = 3Fh) – MRW Only
OP7
OP6
OP5
OP4
OP3
OP2
OP1
OP0
X
Note:
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1. For additional information on MRW RESET see MODE REGISTER WRITE Command
(page 77).
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ACTIVATE Command
ACTIVATE Command
The ACTIVATE command is issued by holding CS# LOW, CA0 LOW, and CA1 HIGH at the
rising edge of the clock. The bank addresses BA[2:0] are used to select the desired bank.
Row addresses are used to determine which row to activate in the selected bank. The
ACTIVATE command must be applied before any READ or WRITE operation can be executed. The device can accept a READ or WRITE command at tRCD after the ACTIVATE
command is issued. After a bank has been activated, it must be precharged before another ACTIVATE command can be applied to the same bank. The bank active and precharge times are defined as tRAS and tRP, respectively. The minimum time interval between successive ACTIVATE commands to the same bank is determined by the RAS cycle time of the device (tRC). The minimum time interval between ACTIVATE commands
to different banks is tRRD.
Figure 14: ACTIVATE Command
CK#
CK
CA[9:0]
T0
T1
T2
Bankn Row addr
row addr
T3
Bankm Row addr Bankn
row addr
col addr
Tn
Col addr
Tn+1
Tn+2
Tn+3
Bankn Row addr
row addr
Bankn
tRRD
tRCD
tRP
tRAS
tRC
CMD
ACTIVATE
NOP
Notes:
ACTIVATE
READ
PRECHARGE
NOP
NOP
ACTIVATE
1. tRCD = 3, tRP = 3, tRRD = 2.
2. A PRECHARGE ALL command uses tRPab timing, and a single-bank PRECHARGE command uses tRPpb timing. In this figure, tRP is used to denote either an all-bank PRECHARGE or a single-bank PRECHARGE.
8-Bank Device Operation
Two rules regarding 8-bank device operation must be observed. One rule restricts the
number of sequential ACTIVATE commands that can be issued; the second provides additional RAS precharge time for a PRECHARGE ALL command.
The 8-Bank Device Sequential Bank Activation Restriction: No more than four banks
can be activated (or refreshed, in the case of REFpb) in a rolling tFAW window. To convert to clocks, divide tFAW[ns] by tCK[ns], and round up to the next integer value. For
example, if RU(tFAW/tCK) is 10 clocks, and an ACTIVATE command is issued in clock n,
no more than three further ACTIVATE commands can be issued at or between clock
n + 1 and n + 9. REFpb also counts as bank activation for purposes of tFAW.
The 8-Bank Device PRECHARGE ALL Provision: tRP for a PRECHARGE ALL command
must equal tRPab, which is greater than tRPpb.
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Read and Write Access Modes
Figure 15: tFAW Timing (8-Bank Devices)
Tn
Tn+
Tm
Tm+
Tx
Tx+
Ty
Ty + 1
Ty + 2
Tz
Tz + 1
Tz + 2
CK#
CK
CA[9:0]
Bank Bank
A
A
Bank Bank
B
B
tRRD
CMD ACTIVATE
Bank Bank
C
C
tRRD
ACTIVATE
NOP
NOP
Bank Bank
D
D
Bank Bank
E
E
tRRD
ACTIVATE
NOP
ACTIVATE
NOP
NOP
NOP
ACTIVATE
NOP
tFAW
Note:
1. Exclusively for 8-bank devices.
Read and Write Access Modes
After a bank is activated, a READ or WRITE command can be issued with CS# LOW, CA0
HIGH, and CA1 LOW at the rising edge of the clock. CA2 must also be defined at this
time to determine whether the access cycle is a READ operation (CA2 HIGH) or a
WRITE operation (CA2 LOW). A single READ or WRITE command initiates a burst
READ or burst WRITE operation on successive clock cycles.
A new burst access must not interrupt the previous 4-bit burst operation when BL = 4.
When BL = 8 or BL = 16, READs can be interrupted by READs and WRITEs can be interrupted by WRITEs, provided that the interrupt occurs on a 4-bit boundary and that
tCCD is met.
Burst READ Command
The burst READ command is initiated with CS# LOW, CA0 HIGH, CA1 LOW, and CA2
HIGH at the rising edge of the clock. The command address bus inputs, CA5r–CA6r and
CA1f–CA9f, determine the starting column address for the burst. The read latency (RL)
is defined from the rising edge of the clock on which the READ command is issued to
the rising edge of the clock from which the tDQSCK delay is measured. The first valid
data is available RL × tCK + tDQSCK + tDQSQ after the rising edge of the clock when the
READ command is issued. The data strobe output is driven LOW tRPRE before the first
valid rising strobe edge. The first bit of the burst is synchronized with the first rising
edge of the data strobe. Each subsequent data-out appears on each DQ pin, edgealigned with the data strobe. The RL is programmed in the mode registers.
Pin input timings for the data strobe are measured relative to the crosspoint of DQS and
its complement, DQS#.
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Burst READ Command
Figure 16: READ Output Timing – tDQSCK (MAX)
RL - 1
RL
tCH
CK#
CK
RL + BL/ 2
tCL
tHZ(DQS)
tDQSCKmax
tLZ(DQS)
tRPRE
tRPST
DQS#
DQS
tQH
tQH
tDQSQmax
DOUT
DQ
tDQSQmax
DOUT
DOUT
tLZ(DQ)
DOUT
tHZ(DQ)
Transitioning data
Notes:
1. tDQSCK can span multiple clock periods.
2. An effective burst length of 4 is shown.
Figure 17: READ Output Timing – tDQSCK (MIN)
RL - 1
RL
CK#
CK
tCH
RL + BL/2
tCL
tHZ(DQS)
tDQSCKmin
tLZ(DQS)
tRPRE
tRPST
DQS#
DQS
tQH
tQH
tDQSQmax
tDQSQmax
DOUT
DQ
DOUT
DOUT
DOUT
tHZ(DQ)
tLZ(DQ)
Transitioning data
Note:
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1. An effective burst length of 4 is shown.
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2Gb: x16, x32, x64 Automotive LPDDR2 SDRAM
Burst READ Command
Figure 18: Burst READ – RL = 5, BL = 4, tDQSCK > tCK
CK#
CK
T0
T1
T2
T3
T4
T5
T6
T7
T8
RL = 5
CA[9:0]
CMD
Bank n
col addr
Col addr
READ
NOP
NOP
NOP
NOP
NOP
NOP
NOP
NOP
tDQSCK
DQS#
DQS
DQ
DOUT A0
DOUT A1
DOUT A2
DOUT A3
Transitioning data
Figure 19: Burst READ – RL = 3, BL = 8, tDQSCK < tCK
CK#
CK
T0
T1
T2
T3
T4
T5
T6
T7
T8
RL = 3
CA[9:0]
CMD
Bank n
col addr
Col addr
READ
NOP
NOP
NOP
NOP
NOP
NOP
NOP
NOP
tDQSCK
DQS#
DQS
DQ
DOUT A0
DOUT A1
DOUT A2
DOUT A3
DOUT A4
DOUT A5
DOUT A6
DOUT A7
Transitioning data
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Burst READ Command
Figure 20: tDQSCKDL Timing
Tn
Tn + 1
Tn + 2
Tn + 3
Tn + 4
Tn + 5
Tn + 6
Tn + 7
Tn + 8
CK#
CK
RL = 5
CA
[9:0]
Bank n
col addr
CMD
Col addr
READ
NOP
NOP
NOP
NOP
NOP
NOP
NOP
NOP
tDQSCKn
DQS#
DQS
DQ
DOUT A0
DOUT A1
DOUT A2
DOUT A3
32ms maximum…
1
Tm
Tm + 1
Tm + 2
Tm + 3
Tm + 4
Tm + 5
Tm + 6
Tm + 7
Tm + 8
CK#
CK
RL = 5
CA
[9:0]
Bank n
col addr
CMD
Col addr
READ
NOP
NOP
NOP
NOP
NOP
NOP
NOP
NOP
tDQSCKm
DQS#
DQS
DQ
DOUT A0
DOUT A1
DOUT A2
DOUT A3
…32ms maximum
Transitioning data
1
Notes:
PDF: 09005aef8597bf6f
2gb_automotive_lpddr2_u89n.pdf - Rev. D 4/15 EN
1. tDQSCKDL = (tDQSCKn - tDQSCKm).
2. tDQSCKDL (MAX) is defined as the maximum of ABS (tDQSCKn - tDQSCKm) for any
(tDQSCKn, tDQSCKm) pair within any 32ms rolling window.
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2Gb: x16, x32, x64 Automotive LPDDR2 SDRAM
Burst READ Command
Figure 21: tDQSCKDM Timing
Tn
Tn + 1
Tn + 2
Tn + 3
Tn + 4
Tn + 5
Tn + 6
Tn + 7
Tn + 8
CK#
CK
RL = 5
CA
[9:0]
Bank n
col addr
CMD
Col addr
READ
NOP
NOP
NOP
NOP
NOP
NOP
NOP
NOP
tDQSCKn
DQS#
DQS
DQ
DOUT A0
DOUT A1
DOUT A2
DOUT A3
1.6µs maximum…
1
Tm
Tm + 1
Tm + 2
Tm + 3
Tm + 4
Tm + 5
Tm + 6
Tm + 7
Tm + 8
CK#
CK
RL = 5
CA
[9:0]
Bankn
col addr
CMD
Col addr
READ
NOP
NOP
NOP
NOP
NOP
NOP
NOP
NOP
tDQSCKm
DQS#
DQS
DQ
DOUT A0
DOUT A1
DOUT A2
DOUT A3
…1.6µs maximum
Transitioning data
1
Notes:
PDF: 09005aef8597bf6f
2gb_automotive_lpddr2_u89n.pdf - Rev. D 4/15 EN
1. tDQSCKDM = (tDQSCKn - tDQSCKm).
2. tDQSCKDM (MAX) is defined as the maximum of ABS (tDQSCKn - tDQSCKm) for any
(tDQSCKn, tDQSCKm) pair within any 1.6μs rolling window.
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2Gb: x16, x32, x64 Automotive LPDDR2 SDRAM
Burst READ Command
Figure 22: tDQSCKDS Timing
Tn
Tn + 1
Tn + 2
Tn + 3
Tn + 4
Tn + 5
Tn + 6
Tn + 7
Tn + 8
CK#
CK
RL = 5
CA
[9:0]
Bank n
col addr
CMD
Col addr
READ
NOP
NOP
NOP
NOP
NOP
NOP
NOP
NOP
tDQSCKn
DQS#
DQS
DQ
DOUT A0
DOUT A1
DOUT A2
DOUT A3
DOUT A4
160ns maximum…
1
Tm
Tm + 1
Tm + 2
Tm + 3
Tm + 4
Tm + 5
Tm + 6
Tm + 7
Tm + 8
CK#
CK
RL = 5
CA
[9:0]
Bank n
col addr
CMD
Col addr
READ
NOP
NOP
NOP
NOP
NOP
NOP
NOP
NOP
tDQSCKm
DQS#
DQS
DQ
DOUT A2
DOUT A3
DOUT A0
DOUT A1
DOUT A2
DOUT A3
DOUT A0
DOUT A1
DOUT A2
DOUT A3
DOUT A0
DOUT A1
DOUT A2
DOUT A3
DOUT A0
DOUT A1
DOUT A2
DOUT A3
…160ns maximum
Transitioning data
1
Notes:
PDF: 09005aef8597bf6f
2gb_automotive_lpddr2_u89n.pdf - Rev. D 4/15 EN
1. tDQSCKDS = (tDQSCKn - tDQSCKm).
2. tDQSCKDS (MAX) is defined as the maximum of ABS (tDQSCKn - tDQSCKm) for any
(tDQSCKn, tDQSCKm) pair for READs within a consecutive burst, within any 160ns rolling
window.
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2Gb: x16, x32, x64 Automotive LPDDR2 SDRAM
Burst READ Command
Figure 23: Burst READ Followed by Burst WRITE – RL = 3, WL = 1, BL = 4
CK#
CK
T0
T1
T2
T3
T4
T5
T6
T7
RL = 3
CA[9:0]
CMD
Bank n
col addr
WL = 1
Bank n
col addr
Col addr
READ
T8
NOP
NOP
NOP
NOP
NOP
tDQSCK
Col addr
WRITE
NOP
NOP
tDQSSmin
BL/2
DQS#
DQS
DQ
DOUT A0
DOUT A1
DOUT A2
DOUT A3
DIN A0
DIN A1
D
Transitioning data
The minimum time from the burst READ command to the burst WRITE command is
defined by the read latency (RL) and the burst length (BL). Minimum READ-to-WRITE
latency is RL + RU(tDQSCK(MAX)/tCK) + BL/2 + 1 - WL clock cycles. Note that if a READ
burst is truncated with a burst TERMINATE (BST) command, the effective burst length
of the truncated READ burst should be used for BL when calculating the minimum
READ-to-WRITE delay.
Figure 24: Seamless Burst READ – RL = 3, BL = 4, tCCD = 2
CK#
CK
T0
T1
T2
T3
T4
T5
T6
T7
T8
RL = 3
CA[9:0]
Bankn
Col addr a
col addr a
tCCD
CMD
READ
Bankn
Col addr b
col addr b
=2
NOP
READ
NOP
NOP
NOP
NOP
NOP
NOP
DQS#
DQS
DQ
DOUT A0
DOUT A1
DOUT A2
DOUT A3
DOUT B0
DOUT B1
DOUT B2
DOUT B3
Transitioning data
A seamless burst READ operation is supported by enabling a READ command at every
other clock cycle for BL = 4 operation, every fourth clock cycle for BL = 8 operation, and
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2Gb: x16, x32, x64 Automotive LPDDR2 SDRAM
Burst WRITE Command
every eighth clock cycle for BL = 16 operation. This operation is supported as long as the
banks are activated, whether the accesses read the same or different banks.
READs Interrupted by a READ
A burst READ can be interrupted by another READ with a 4-bit burst boundary, provided that tCCD is met.
Figure 25: READ Burst Interrupt Example – RL = 3, BL = 8, tCCD = 2
CK#
CK
T0
T1
T2
T3
T4
T5
T6
T7
T8
RL = 3
CA[9:0]
Bank n
Col addr a
col addr a
Bank n
Col addr b
col addr b
tCCD
CMD
READ
=2
NOP
READ
NOP
NOP
NOP
NOP
NOP
NOP
DQS#
DQS
DQ
DOUT A0
DOUT A1
DOUT A2
DOUT A3
DOUT B0
DOUT B1
DOUT B2
DOUT B3
DOUT B4
DOUT B5
Transitioning data
Note:
1. READs can only be interrupted by other READs or the BST command.
Burst WRITE Command
The burst WRITE command is initiated with CS# LOW, CA0 HIGH, CA1 LOW, and CA2
LOW at the rising edge of the clock. The command address bus inputs, CA5r–CA6r and
CA1f–CA9f, determine the starting column address for the burst. Write latency (WL) is
defined from the rising edge of the clock on which the WRITE command is issued to the
rising edge of the clock from which the tDQSS delay is measured. The first valid data
must be driven WL × tCK + tDQSS from the rising edge of the clock from which the
WRITE command is issued. The data strobe signal (DQS) must be driven LOW tWPRE
prior to data input. The burst cycle data bits must be applied to the DQ pins tDS prior to
the associated edge of the DQS and held valid until tDH after that edge. Burst data is
sampled on successive edges of the DQS until the 4-, 8-, or 16-bit burst length is completed. After a burst WRITE operation, tWR must be satisfied before a PRECHARGE
command to the same bank can be issued.
Pin input timings are measured relative to the crosspoint of DQS and its complement,
DQS#.
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2Gb: x16, x32, x64 Automotive LPDDR2 SDRAM
Burst WRITE Command
Figure 26: Data Input (WRITE) Timing
tWPRE
DQS
tDQSH
tDQSL
VIH(DC)
VIH(AC)
tWPST
DQS#
DQS#
DQS
VIH(AC)
DIN
DQ
VIL(AC)
tDS
DIN
tDH
VIL(DC)
VIH(AC)
tDS
VIH(DC)
DIN
tDH
VIL(AC)
VIH(DC)
tDS
DIN
tDH
VIL(DC) tDS
VIH(AC)
tDH
VIH(DC)
DM
VIL(AC)
VIL(DC)
VIL(AC)
VIL(DC)
Don’t Care
Figure 27: Burst WRITE – WL = 1, BL = 4
CK#
CK
T0
T1
T2
T3
T4
Tx
Tx + 1
Ty
Ty + 1
WL = 1
CA[9:0]
CMD
Bank n
col addr
Col addr
WRITE
Case 1: tDQSSmax
Bank n
Row addr
row addr
Bank n
NOP
NOP
tDQSSmax
NOP
tDSS
NOP
tDSS
PRECHARGE
NOP
ACTIVATE
NOP
Completion of burst WRITE
DQS#
DQS
tWR
DQ
Case 2: tDQSSmin
DQS#
DQS
DIN A0
tDQSSmin
DIN A1
tDSH
DIN A2
DIN A3
tDSH
tRP
tWR
DQ
DIN A0
DIN A1
DIN A2
DIN A3
Transitioning data
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2Gb: x16, x32, x64 Automotive LPDDR2 SDRAM
Burst WRITE Command
Figure 28: Burst WRITE Followed by Burst READ – RL = 3, WL = 1, BL = 4
CK#
CK
T0
T1
T2
T3
T4
T5
T6
T7
RL = 3
WL = 1
CA[9:0]
T8
Bank n
Col addr b
col addr b
Bank m
Col addr a
col addr a
tWTR
CMD
WRITE
NOP
NOP
NOP
NOP
NOP
READ
NOP
NOP
DQS#
DQS
DQ
DIN A0
DIN A1
DIN A2
DIN A3
Transitioning data
Notes:
1. The minimum number of clock cycles from the burst WRITE command to the burst READ
command for any bank is [WL + 1 + BL/2 + RU(tWTR/tCK)].
2. tWTR starts at the rising edge of the clock after the last valid input data.
3. If a WRITE burst is truncated with a BST command, the effective burst length of the
truncated WRITE burst should be used as BL to calculate the minimum WRITE-to-READ
delay.
Figure 29: Seamless Burst WRITE – WL = 1, BL = 4, tCCD = 2
CK#
CK
T0
T1
T2
T3
T4
T5
T6
T7
T8
WL = 1
CA[9:0]
Bank m
Col addr a
col addr a
Bank n
Col addr b
col addr b
tCCD
CMD
WRITE
=2
NOP
WRITE
NOP
NOP
NOP
NOP
NOP
NOP
DQS#
DQS
DQ
DIN A0
DIN A1
DIN A2
DIN A3
DIN B0
DIN B1
DIN B2
DIN B3
Transitioning data
Note:
PDF: 09005aef8597bf6f
2gb_automotive_lpddr2_u89n.pdf - Rev. D 4/15 EN
1. The seamless burst WRITE operation is supported by enabling a WRITE command every
other clock for BL = 4 operation, every four clocks for BL = 8 operation, or every eight
clocks for BL = 16 operation. This operation is supported for any activated bank.
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2Gb: x16, x32, x64 Automotive LPDDR2 SDRAM
BURST TERMINATE Command
WRITEs Interrupted by a WRITE
A burst WRITE can only be interrupted by another WRITE with a 4-bit burst boundary,
provided that tCCD (MIN) is met.
A WRITE burst interrupt can occur on even clock cycles after the initial WRITE command, provided that tCCD (MIN) is met.
Figure 30: WRITE Burst Interrupt Timing – WL = 1, BL = 8, tCCD = 2
CK#
CK
T0
T1
T2
T3
T4
T5
T6
T7
T8
WL = 1
CA[9:0]
Bank m
Col addr a
col addr a
Bank n
Col addr b
col addr b
tCCD
CMD
WRITE
=2
NOP
WRITE
NOP
NOP
NOP
NOP
NOP
NOP
DQS#
DQS
DQ
DIN A0
DIN A1
DIN A2
DIN A3
DIN B0
DIN B1
DIN B2
DIN B3
DIN B4
DIN B5
DIN B6
DIN B7
Transitioning data
Notes:
1. WRITEs can only be interrupted by other WRITEs or the BST command.
2. The effective burst length of the first WRITE equals two times the number of clock cycles
between the first WRITE and the interrupting WRITE.
BURST TERMINATE Command
The BURST TERMINATE (BST) command is initiated with CS# LOW, CA0 HIGH, CA1
HIGH, CA2 LOW, and CA3 LOW at the rising edge of the clock. A BST command can only
be issued to terminate an active READ or WRITE burst. Therefore, a BST command can
only be issued up to and including BL/2 - 1 clock cycles after a READ or WRITE command. The effective burst length of a READ or WRITE command truncated by a BST
command is as follows:
• Effective burst length = 2 × (number of clock cycles from the READ or WRITE command to the BST command).
• If a READ or WRITE burst is truncated with a BST command, the effective burst length
of the truncated burst should be used for BL when calculating the minimum READto-WRITE or WRITE-to-READ delay.
• The BST command only affects the most recent READ or WRITE command. The BST
command truncates an ongoing READ burst RL × tCK + tDQSCK + tDQSQ after the rising edge of the clock where the BST command is issued. The BST command truncates
an ongoing WRITE burst WL × tCK + tDQSS after the rising edge of the clock where the
BST command is issued.
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2Gb: x16, x32, x64 Automotive LPDDR2 SDRAM
BURST TERMINATE Command
• The 4-bit prefetch architecture enables BST command assertion on even clock cycles
following a WRITE or READ command. The effective burst length of a READ or WRITE
command truncated by a BST command is thus an integer multiple of four.
Figure 31: Burst WRITE Truncated by BST – WL = 1, BL = 16
CK#
CK
T0
T1
T2
T3
T4
T5
T6
T7
T8
WL = 1
CA[9:0]
CMD
Bank m
col addr a Col addr a
WRITE
NOP
NOP
NOP
BST
NOP
NOP
NOP
NOP
WL × tCK + tDQSS
DQS#
DQS
DQ
DIN A0
DIN A1
DIN A2
DIN A3
DIN A4
DIN A5
DIN A6
DIN A7
BST prohibited
Notes:
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2gb_automotive_lpddr2_u89n.pdf - Rev. D 4/15 EN
Transitioning data
1. The BST command truncates an ongoing WRITE burst WL × tCK + tDQSS after the rising
edge of the clock where the BST command is issued.
2. BST can only be issued an even number of clock cycles after the WRITE command.
3. Additional BST commands are not supported after T4 and must not be issued until after
the next READ or WRITE command.
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2Gb: x16, x32, x64 Automotive LPDDR2 SDRAM
Write Data Mask
Figure 32: Burst READ Truncated by BST – RL = 3, BL = 16
CK#
CK
T0
T1
T2
T3
T4
T5
T6
T7
T8
RL = 3
CA[9:0]
CMD
Bank n
Col addr a
col addr a
READ
NOP
NOP
NOP
BST
NOP
NOP
NOP
NOP
RL × tCK + tDQSCK + tDQSQ
DQS#
DQS
DQ
DOUT A0
DOUT A1
DOUT A2
DOUT A3
DOUT A4
DOUT A5
DOUT A6
DOUT A7
BST prohibited
Transitioning data
1. The BST command truncates an ongoing READ burst (RL × tCK + tDQSCK + tDQSQ) after
the rising edge of the clock where the BST command is issued.
2. BST can only be issued an even number of clock cycles after the READ command.
3. Additional BST commands are not supported after T4 and must not be issued until after
the next READ or WRITE command.
Notes:
Write Data Mask
On LPDDR2 devices, one write data mask (DM) pin for each data byte (DQ) is supported, consistent with the implementation on LPDDR SDRAM. Each DM can mask its respective DQ for any given cycle of the burst. Data mask timings match data bit timing,
but are inputs only. Internal data mask loading is identical to data bit loading to ensure
matched system timing.
Figure 33: Data Mask Timing
DQS
DQS#
DQ
VIH(AC)
tDS
tDH
VIH(DC) VIH(AC)
tDS
tDH
VIH(DC)
DM
VIL(AC)
VIL(DC) VIL(AC)
VIL(DC)
Don’t Care
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2Gb: x16, x32, x64 Automotive LPDDR2 SDRAM
PRECHARGE Command
Figure 34: Write Data Mask – Second Data Bit Masked
CK#
CK
tWR
tWTR
WL = 2
CMD
WRITE
Case 1: t DQSSmin
tDQSSmin
DQS
DQS#
DOUT 0 DOUT 1 DOUT 2 DOUT 3
DQ
DM
Case 2: t DQSSmax
tDQSSmax
DQS#
DQS
DOUT 0 DOUT 1 DOUT 2 DOUT 3
DQ
DM
Don’t Care
Note:
1. For the data mask function, WL = 2, BL = 4 is shown; the second data bit is masked.
PRECHARGE Command
The PRECHARGE command is used to precharge or close a bank that has been activated. The PRECHARGE command is initiated with CS# LOW, CA0 HIGH, CA1 HIGH, CA2
LOW, and CA3 HIGH at the rising edge of the clock. The PRECHARGE command can be
used to precharge each bank independently or all banks simultaneously. For 4-bank devices, the AB flag and bank address bits BA0 and BA1 are used to determine which
bank(s) to precharge. For 8-bank devices, the AB flag and the bank address bits BA0,
BA1, and BA2 are used to determine which bank(s) to precharge. The precharged
bank(s) will be available for subsequent row access tRPab after an all bank PRECHARGE
command is issued, or tRPpb after a single-bank PRECHARGE command is issued.
To ensure that 8-bank devices can meet the instantaneous current demand required to
operate, the row precharge time (tRP) for an all bank PRECHARGE in 8-bank devices
(tRPab) will be longer than the row precharge time for a single-bank PRECHARGE
(tRPpb). For 4-bank devices, tRPab is equal to tRPpb.
ACTIVATE to PRECHARGE timing is shown in ACTIVATE Command.
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2Gb: x16, x32, x64 Automotive LPDDR2 SDRAM
PRECHARGE Command
Table 43: Bank Selection for PRECHARGE by Address Bits
AB (CA4r)
BA2
(CA9r)
BA1
(CA8r)
BA0
(CA7r)
0
0
0
0
Bank 0 only
Bank 0 only
0
0
0
1
Bank 1 only
Bank 1 only
0
0
1
0
Bank 2 only
Bank 2 only
0
0
1
1
Bank 3 only
Bank 3 only
0
1
0
0
Bank 0 only
Bank 4 only
0
1
0
1
Bank 1 only
Bank 5 only
0
1
1
0
Bank 2 only
Bank 6 only
1
1
1
Bank 3 only
Bank 7 only
All banks
All banks
0
1
Precharged Bank(s) Precharged Bank(s)
4-Bank Device
8-Bank Device
Don’t Care Don’t Care Don’t Care
READ Burst Followed by PRECHARGE
For the earliest possible precharge, the PRECHARGE command can be issued BL/2
clock cycles after a READ command. A new bank ACTIVATE command can be issued to
the same bank after the row precharge time (tRP) has elapsed. A PRECHARGE command cannot be issued until after tRAS is satisfied.
The minimum READ-to-PRECHARGE time (tRTP) must also satisfy a minimum analog
time from the rising clock edge that initiates the last 4-bit prefetch of a READ command. tRTP begins BL/2 - 2 clock cycles after the READ command.
If the burst is truncated by a BST command, the effective BL value is used to calculate
when tRTP begins.
Figure 35: READ Burst Followed by PRECHARGE – RL = 3, BL = 8, RU(tRTP(MIN)/tCK) = 2
CK#
CK
T0
T1
T2
T3
T4
T5
T6
T7
T8
RL = 3
BL/2
CA[9:0]
Bank m
col addr a Col addr a
Bank m
row addr
Bank m
tRP
tRTP
CMD
READ
NOP
NOP
NOP
Row addr
PRECHARGE
NOP
NOP
ACTIVATE
NOP
DQS#
DQS
DQ
DOUT A0
DOUT A1
DOUT A2
DOUT A3
DOUT A4
DOUT A5
DOUT A6
DOUT A7
Transitioning data
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2Gb: x16, x32, x64 Automotive LPDDR2 SDRAM
PRECHARGE Command
Figure 36: READ Burst Followed by PRECHARGE – RL = 3, BL = 4, RU(tRTP(MIN)/tCK) = 3
CK#
CK
T0
T1
T2
T3
T4
T5
T6
T7
T8
BL/2
RL = 3
CA[9:0]
Bank m
col addr a Col addr a
tRTP
CMD
READ
Bank m
row addr
Bank m
NOP
Row addr
tRP
=3
NOP
PRECHARGE
NOP
NOP
ACTIVATE
NOP
NOP
DQS#
DQS
DQ
DOUT A0
DOUT A1
DOUT A2
DOUT A3
Transitioning data
WRITE Burst Followed by PRECHARGE
For WRITE cycles, a WRITE recovery time ( tWR) must be provided before a PRECHARGE
command can be issued. tWR delay is referenced from the completion of the burst
WRITE. The PRECHARGE command must not be issued prior to the tWR delay. For
WRITE-to-PRECHARGE timings, see the PRECHARGE and Auto Precharge Clarification
table.
These devices write data to the array in prefetch quadruples (prefetch = 4). An internal
WRITE operation can only begin after a prefetch group has been completely latched.
The minimum WRITE-to-PRECHARGE time for commands to the same bank is WL +
BL/2 + 1 + RU(tWR/tCK) clock cycles. For untruncated bursts, BL is the value set in the
mode register. For truncated bursts, BL is the effective burst length.
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2Gb: x16, x32, x64 Automotive LPDDR2 SDRAM
PRECHARGE Command
Figure 37: WRITE Burst Followed by PRECHARGE – WL = 1, BL = 4
CK#
CK
T0
T1
T2
T3
T4
Tx
Tx + 1
Ty
Ty + 1
WL = 1
CA[9:0]
Bank n
col addr
Col addr
WRITE
Case 1: t DQSSmax
NOP
NOP
NOP
NOP
tDQSSmax
Row addr
≥ tRP
tWR
CMD
Bank n
row addr
Bank n
PRECHARGE
NOP
ACTIVATE
NOP
Completion of burst WRITE
DQS#
DQS
DQ
Case 2: t DQSSmin
DIN A0
DIN A1
DIN A2
DIN A3
tDQSSmin
DQS#
DQS
DQ
DIN A0
DIN A1
DIN A2
DIN A3
Transitioning data
Auto Precharge
Before a new row can be opened in an active bank, the active bank must be precharged
using either the PRECHARGE command or the auto precharge function. When a READ
or WRITE command is issued to the device, the auto precharge bit (AP) can be set to
enable the active bank to automatically begin precharge at the earliest possible moment during the burst READ or WRITE cycle.
If AP is LOW when the READ or WRITE command is issued, then normal READ or
WRITE burst operation is executed and the bank remains active at the completion of
the burst.
If AP is HIGH when the READ or WRITE command is issued, the auto precharge function is engaged. This feature enables the PRECHARGE operation to be partially or completely hidden during burst READ cycles (dependent upon READ or WRITE latency),
thus improving system performance for random data access.
READ Burst with Auto Precharge
If AP (CA0f) is HIGH when a READ command is issued, the READ with auto precharge
function is engaged.
These devices start an auto precharge on the rising edge of the clock BL/2 or BL/2 - 2 +
RU(tRTP/tCK) clock cycles later than the READ with auto precharge command, whichever is greater. For auto precharge calculations, see the PRECHARGE and Auto Precharge Clarification table.
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2Gb: x16, x32, x64 Automotive LPDDR2 SDRAM
PRECHARGE Command
Following an auto precharge operation, an ACTIVATE command can be issued to the
same bank if the following two conditions are satisfied simultaneously:
• The RAS precharge time (tRP) has been satisfied from the clock at which the auto precharge begins.
• The RAS cycle time (tRC) from the previous bank activation has been satisfied.
Figure 38: READ Burst with Auto Precharge – RL = 3, BL = 4, RU(tRTP(MIN)/tCK) = 2
CK#
CK
T0
T1
T2
T3
T4
T5
T6
T7
T8
BL/2
RL = 3
CA[9:0]
Bankm
Row addr
row addr
Bankm
Col addr a
col addr a
≥ tRPpb
tRTP
CMD
READ w/AP
NOP
NOP
NOP
NOP
ACTIVATE
NOP
NOP
NOP
DQS#
DQS
DQ
DOUT A0
DOUT A1
DOUT A2
DOUT A3
Transitioning data
WRITE Burst with Auto Precharge
If AP (CA0f) is HIGH when a WRITE command is issued, the WRITE with auto precharge
function is engaged. The device starts an auto precharge at the clock rising edge tWR
cycles after the completion of the burst WRITE.
Following a WRITE with auto precharge, an ACTIVATE command can be issued to the
same bank if the following two conditions are met:
• The RAS precharge time (tRP) has been satisfied from the clock at which the auto precharge begins.
• The RAS cycle time (tRC) from the previous bank activation has been satisfied.
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2Gb: x16, x32, x64 Automotive LPDDR2 SDRAM
PRECHARGE Command
Figure 39: WRITE Burst with Auto Precharge – WL = 1, BL = 4
CK#
CK
T0
T1
T2
T3
T4
T5
T6
T7
T8
WL = 1
CA[9:0]
Bankn
col addr
Bankn Row addr
row addr
Col addr
tWR
CMD
WRITE
NOP
NOP
NOP
≥ tRPpb
NOP
NOP
NOP
ACTIVATE
NOP
DQS#
DQS
DQ
DIN A0
DIN A1
DIN A2
DIN A3
Transitioning data
Table 44: PRECHARGE and Auto Precharge Clarification
From
Command
READ
BST
READ w/AP
To Command
PRECHARGE to same bank as READ
Minimum Delay Between Commands
BL/2 + MAX(2, RU(tRTP/tCK)) - 2
RU(tRTP/tCK))
Notes
CLK
1
CLK
1
1
PRECHARGE ALL
BL/2 + MAX(2,
PRECHARGE to same bank as READ
1
CLK
PRECHARGE ALL
1
CLK
1
PRECHARGE to same bank as READ w/AP
BL/2 + MAX(2, RU(tRTP/tCK)) - 2
CLK
1, 2
PRECHARGE ALL
BL/2 + MAX(2, RU(tRTP/tCK)) - 2
CLK
1
CLK
1
ACTIVATE to same bank as READ w/AP
BL/2 + MAX(2,
RU(tRTP/tCK))
-2
Unit
-2+
RU(tRPpb/
tCK)
WRITE
BST
WRITE or WRITE w/AP (same bank)
Illegal
CLK
3
WRITE or WRITE w/AP (different bank)
RL + BL/2 + RU(tDQSCKmax/tCK) - WL + 1
CLK
3
READ or READ w/AP (same bank)
Illegal
CLK
3
READ or READ w/AP (different bank)
BL/2
CLK
3
RU(tWR/tCK)
PRECHARGE to same bank as WRITE
WL + BL/2 +
+1
CLK
1
PRECHARGE ALL
WL + BL/2 + RU(tWR/tCK) + 1
CLK
1
PRECHARGE to same bank as WRITE
PRECHARGE ALL
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WL +
RU(tWR/tCK)
+1
CLK
1
WL +
RU(tWR/tCK)
+1
CLK
1
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2Gb: x16, x32, x64 Automotive LPDDR2 SDRAM
REFRESH Command
Table 44: PRECHARGE and Auto Precharge Clarification (Continued)
From
Command
To Command
WRITE w/AP PRECHARGE to same bank as WRITE w/AP
Minimum Delay Between Commands
WL + BL/2 + RU(tWR/tCK) + 1
Unit
Notes
CLK
1, 2
CLK
1
CLK
1
WL + BL/2 +
RU(tWR/tCK)
ACTIVATE to same bank as WRITE w/AP
WL + BL/2 +
RU(tWR/tCK)
WRITE or WRITE w/AP (same bank)
Illegal
CLK
3
WRITE or WRITE w/AP (different bank)
BL/2
CLK
3
READ or READ w/AP (same bank)
Illegal
CLK
3
CLK
3
PRECHARGE ALL
READ or READ w/AP (different bank)
PRECHARGE PRECHARGE to same bank as PRECHARGE
WL + BL/2 +
+1
+1+
RU(tWTR/tCK)
+1
RU(tRPpb/tCK)
1
CLK
1
PRECHARGE ALL
1
CLK
1
PRECHARGE PRECHARGE
ALL
PRECHARGE ALL
1
CLK
1
1
CLK
1
Notes:
1. For a given bank, the PRECHARGE period should be counted from the latest PRECHARGE
command—either a one-bank PRECHARGE or PRECHARGE ALL—issued to that bank.
The PRECHARGE period is satisfied after tRP, depending on the latest PRECHARGE command issued to that bank.
2. Any command issued during the specified minimum delay time is illegal.
3. After READ with auto precharge, seamless READ operations to different banks are supported. After WRITE with auto precharge, seamless WRITE operations to different banks
are supported. READ with auto precharge and WRITE with auto precharge must not be
interrupted or truncated.
REFRESH Command
The REFRESH command is initiated with CS# LOW, CA0 LOW, CA1 LOW, and CA2 HIGH
at the rising edge of the clock. Per-bank REFRESH is initiated with CA3 LOW at the rising edge of the clock. All-bank REFRESH is initiated with CA3 HIGH at the rising edge of
the clock. Per-bank REFRESH is only supported in devices with eight banks.
A per-bank REFRESH command (REFpb) performs a per-bank REFRESH operation to
the bank scheduled by the bank counter in the memory device. The bank sequence for
per-bank REFRESH is fixed to be a sequential round-robin: 0-1-2-3-4-5-6-7-0-1-.... The
bank count is synchronized between the controller and the SDRAM by resetting the
bank count to zero. Synchronization can occur upon issuing a RESET command or at
every exit from self refresh.
A bank must be idle before it can be refreshed. The controller must track the bank being
refreshed by the per-bank REFRESH command.
The REFpb command must not be issued to the device until the following conditions
have been met:
• tRFCab has been satisfied after the prior REFab command
• tRFCpb has been satisfied after the prior REFpb command
• tRP has been satisfied after the prior PRECHARGE command to that bank
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REFRESH Command
• tRRD has been satisfied after the prior ACTIVATE command (if applicable, for example after activating a row in a different bank than the one affected by the REFpb command)
The target bank is inaccessible during per-bank REFRESH cycle time (tRFCpb), however, other banks within the device are accessible and can be addressed during the cycle.
During the REFpb operation, any of the banks other than the one being refreshed can
be maintained in an active state or accessed by a READ or WRITE command.
When the per-bank REFRESH cycle has completed, the affected bank will be in the idle
state.
After issuing REFpb, the following conditions must be met:
•
•
•
•
tRFCpb
must be satisfied before issuing a REFab command
must be satisfied before issuing an ACTIVATE command to the same bank
tRRD must be satisfied before issuing an ACTIVATE command to a different bank
tRFCpb must be satisfied before issuing another REFpb command
tRFCpb
An all-bank REFRESH command (REFab) issues a REFRESH command to all banks. All
banks must be idle when REFab is issued (for instance, by issuing a PRECHARGE ALL
command prior to issuing an all-bank REFRESH command). REFab also synchronizes
the bank count between the controller and the SDRAM to zero. The REFab command
must not be issued to the device until the following conditions have been met:
• tRFCab has been satisfied following the prior REFab command
• tRFCpb has been satisfied following the prior REFpb command
• tRP has been satisfied following the prior PRECHARGE commands
After an all-bank REFRESH cycle has completed, all banks will be idle. After issuing REFab:
• tRFCab latency must be satisfied before issuing an ACTIVATE command
• tRFCab latency must be satisfied before issuing a REFab or REFpb command
Table 45: REFRESH Command Scheduling Separation Requirements
Symbol
Minimum
Delay
From
tRFCab
REFab
To
Notes
REFab
ACTIVATE command to any bank
REFpb
tRFCpb
REFpb
REFab
ACTIVATE command to same bank as REFpb
REFpb
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2Gb: x16, x32, x64 Automotive LPDDR2 SDRAM
REFRESH Command
Table 45: REFRESH Command Scheduling Separation Requirements (Continued)
Symbol
Minimum
Delay
From
tRRD
REFpb
To
Notes
ACTIVATE command to a different bank than REFpb
ACTIVATE REFpb
1
ACTIVATE command to a different bank than the prior
ACTIVATE command
Note:
1. A bank must be in the idle state before it is refreshed, so REFab is prohibited following
an ACTIVATE command. REFpb is supported only if it affects a bank that is in the idle
state.
Mobile LPDDR2 devices provide significant flexibility in scheduling REFRESH commands as long as the required boundary conditions are met (see the tSRF Definition figure).
In the most straightforward implementations, a REFRESH command should be scheduled every tREFI. In this case, self refresh can be entered at any time.
Users may choose to deviate from this regular refresh pattern, for instance, to enable a
period in which no refresh is required. As an example, using a 1Gb LPDDR2 device, the
user can choose to issue a refresh burst of 4096 REFRESH commands at the maximum
supported rate (limited by tREFBW), followed by an extended period without issuing
any REFRESH commands, until the refresh window is complete. The maximum supported time without REFRESH commands is calculated as follows: tREFW - (R/8) × tREFBW
= tREFW - R × 4 × tRFCab.
For example, a 1Gb device at T C ≤ 85˚C can be operated without a refresh for up to 32ms
- 4096 × 4 × 130ns ≈ 30ms.
Both the regular and the burst/pause patterns can satisfy refresh requirements if they
are repeated in every 32ms window. It is critical to satisfy the refresh requirement in
every rolling refresh window during refresh pattern transitions. The supported transition from a burst pattern to a regular distributed pattern is shown in the Supported
Transition from Repetitive REFRESH Burst figure. If this transition occurs immediately
after the burst refresh phase, all rolling tREFW intervals will meet the minimum required number of REFRESH commands.
A nonsupported transition is shown in Figure 42 (page 65). In this example, the regular refresh pattern starts after the completion of the pause phase of the burst/pause refresh pattern. For several rolling tREFW intervals, the minimum number of REFRESH
commands is not satisfied.
Understanding this pattern transition is extremely important, even when only one pattern is employed. In self refresh mode, a regular distributed refresh pattern must be assumed. Micron recommends entering self refresh mode immediately following the
burst phase of a burst/pause refresh pattern; upon exiting self refresh, begin with the
burst phase (see the Recommended Self Refresh Entry and Exit figure).
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2Gb: x16, x32, x64 Automotive LPDDR2 SDRAM
REFRESH Command
Figure 40: Regular Distributed Refresh Pattern
tREFBW
Notes:
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16,384
96ms
12,289
64ms
8,193
8,192
4,097
32ms
4,096
0ms
tREFI
12,288
tREFI
tREFBW
1. Compared to repetitive burst REFRESH with subsequent REFRESH pause.
2. As an example, in a 1Gb LPDDR2 device at TC ≤ 85˚C, the distributed refresh pattern has
one REFRESH command per 7.8μs; the burst refresh pattern has one REFRESH command
per 0.52μs, followed by ≈ 30ms without any REFRESH command.
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REFRESH Command
Figure 41: Supported Transition from Repetitive REFRESH Burst
tREFBW
Notes:
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12,288
64ms
10,240
8,192
4,097
32ms
4,096
0ms
tREFI
96ms
16,384
tREFI
tREFBW
1. Shown with subsequent REFRESH pause to regular distributed refresh pattern.
2. As an example, in a 1Gb LPDDR2 device at TC ≤ 85˚C, the distributed refresh pattern has
one REFRESH command per 7.8μs; the burst refresh pattern has one REFRESH command
per 0.52μs, followed by ≈ 30ms without any REFRESH command.
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REFRESH Command
Figure 42: Nonsupported Transition from Repetitive REFRESH Burst
tREFI
8,193
tREFW
12,288
96ms
10,240
64ms
8,192
4,097
32ms
4,096
0ms
tREFI
= 32ms2
M
Insufficient REFRESH commands
in this refresh window!
tREFBW
Notes:
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tREFBW
1. Shown with subsequent REFRESH pause to regular distributed refresh pattern.
2. There are only ≈ 2048 REFRESH commands in the indicated tREFW window. This does not
provide the required minimum number of REFRESH commands (R).
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2Gb: x16, x32, x64 Automotive LPDDR2 SDRAM
REFRESH Command
Figure 43: Recommended Self Refresh Entry and Exit
8,192
4,097
32ms
4,096
0ms
Self refresh
tREFBW
Note:
tREFBW
1. In conjunction with a burst/pause refresh pattern.
REFRESH Requirements
1. Minimum Number of REFRESH Commands
Mobile LPDDR2 requires a minimum number, R, of REFRESH (REFab) commands within any rolling refresh window (tREFW = 32 ms @ MR4[2:0] = 011 or T C ≤ 85˚C). For actual
values per density and the resulting average refresh interval (tREFI), see Refresh Requirements.
For tREFW and tREFI refresh multipliers at different MR4 settings, see the MR4 Device
Temperature (MA[7:0] = 04h) table.
For devices supporting per-bank REFRESH, a REFab command can be replaced by a full
cycle of eight REFpb commands.
2. Burst REFRESH Limitation
To limit current consumption, a maximum of eight REFab commands can be issued in
any rolling tREFBW (tREFBW = 4 × 8 × tRFCab). This condition does not apply if REFpb
commands are used.
3. REFRESH Requirements and Self Refresh
If any time within a refresh window is spent in self refresh mode, the number of required REFRESH commands in that window is reduced to the following:
R´ = RU
tSRF
t
= R - RU R × SRF
tREFI
tREFW
Where RU represents theround-up function.
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REFRESH Command
Figure 44: tSRF Definition
tREFW
Example A1
tSRF
CKE
Enter self refresh mode
Exit self refresh mode
tREFW
Example B2
tSRF
CKE
Enter self refresh mode
Exit self refresh mode
tREFW
Example C3
tSRF
CKE
Exit self refresh mode
tREFW
Example D4
tSRF2
tSRF1
CKE
Enter self refresh mode
Exit self refresh mode
Enter self refresh mode
Notes:
1.
2.
3.
4.
Exit self refresh mode
Time in self refresh mode is fully enclosed in the refresh window (tREFW).
At self refresh entry.
At self refresh exit.
Several intervals in self refresh during one tREFW interval. In this example, tSRF = tSRF1 +
tSRF2.
Figure 45: All-Bank REFRESH Operation
CK#
CK
CA[9:0]
T0
T1
T2
T3
Tx
Tx + 1
Ty
Ty + 1
AB
≥ tRPab
CMD
T4
PRECHARGE
NOP
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≥ tRFCab
NOP
REFab
NOP
67
≥ tRFCab
REFab
NOP
Valid
NOP
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2Gb: x16, x32, x64 Automotive LPDDR2 SDRAM
SELF REFRESH Operation
Figure 46: Per-Bank REFRESH Operation
CK#
CK
CA[9:0]
T0
T1
Tx
Tx + 1
Ty
Ty + 1
PRECHARGE
Tz
Bank 1
Row A
AB
≥tRPab
CMD
Tx + 2
NOP
≥tRFCpb
NOP
REFpb
NOP
REFRESH to bank 0
Notes:
Tz + 1
Row A
≥tRFCpb
REFpb
REFRESH to bank 1
NOP
ACTIVATE
NOP
ACTIVATE command
to bank 1
1. Prior to T0, the REFpb bank counter points to bank 0.
2. Operations to banks other than the bank being refreshed are supported during the
tRFCpb period.
SELF REFRESH Operation
The SELF REFRESH command can be used to retain data in the array, even if the rest of
the system is powered down. When in the self refresh mode, the device retains data
without external clocking. The device has a built-in timer to accommodate SELF REFRESH operation. The SELF REFRESH command is executed by taking CKE LOW, CS#
LOW, CA0 LOW, CA1 LOW, and CA2 HIGH at the rising edge of the clock.
CKE must be HIGH during the clock cycle preceding a SELF REFRESH command. A
NOP command must be driven in the clock cycle following the SELF REFRESH command. After the power-down command is registered, CKE must be held LOW to keep
the device in self refresh mode.
Mobile LPDDR2 devices can operate in self refresh mode in both the standard and extended temperature ranges. These devices also manage self refresh power consumption
when the operating temperature changes, resulting in the lowest possible power consumption across the operating temperature range. See (page 0 ) for details.
After the device has entered self refresh mode, all external signals other than CKE are
“Don’t Care.” For proper self refresh operation, power supply pins (VDD1, V DD2, V DDQ,
and V DDCA) must be at valid levels. V DDQ can be turned off during self refresh. If V DDQ is
turned off, V REFDQ must also be turned off. Prior to exiting self refresh, both V DDQ and
VREFDQ must be within their respective minimum/maximum operating ranges (see the
Single-Ended AC and DC Input Levels for DQ and DM table). V REFDQ can be at any level
between 0 and V DDQ; V REFCA can be at any level between 0 and V DDCA during self refresh.
Before exiting self refresh, V REFDQ and V REFCA must be within specified limits (see AC
and DC Logic Input Measurement Levels for Single-Ended Signals (page 105)). After entering self refresh mode, the device initiates at least one all-bank REFRESH command
internally during tCKESR. The clock is internally disabled during SELF REFRESH operation to save power. The device must remain in self refresh mode for at least tCKESR. The
user can change the external clock frequency or halt the external clock one clock after
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SELF REFRESH Operation
self refresh entry is registered; however, the clock must be restarted and stable before
the device can exit SELF REFRESH operation.
Exiting self refresh requires a series of commands. First, the clock must be stable prior
to CKE returning HIGH. After the self refresh exit is registered, a minimum delay, at least
equal to the self refresh exit interval (tXSR), must be satisfied before a valid command
can be issued to the device. This provides completion time for any internal refresh in
progress. For proper operation, CKE must remain HIGH throughout tXSR. NOP commands must be registered on each rising clock edge during tXSR.
Using self refresh mode introduces the possibility that an internally timed refresh event
could be missed when CKE is driven HIGH for exit from self refresh mode. Upon exiting
self refresh, at least one REFRESH command (one all-bank command or eight per-bank
commands) must be issued before issuing a subsequent SELF REFRESH command.
Figure 47: SELF REFRESH Operation
CK/CK#
Input clock frequency can be changed
or clock can be stopped during self refresh.
tIHCKE
tIHCKE
CKE
tISCKE
tISCKE
CS#
tCKESR (MIN)
CMD
tXSR (MIN)
Exit
SR
Valid Enter NOP
SR
Enter self refresh mode
NOP NOP Valid
Exit self refresh mode
Don’t Care
Notes:
1. Input clock frequency can be changed or stopped during self refresh, provided that
upon exiting self-refresh, a minimum of two cycles of stable clocks are provided, and the
clock frequency is between the minimum and maximum frequencies for the particular
speed grade.
2. The device must be in the all banks idle state prior to entering self refresh mode.
3. tXSR begins at the rising edge of the clock after CKE is driven HIGH.
4. A valid command can be issued only after tXSR is satisfied. NOPs must be issued during
tXSR.
Partial-Array Self Refresh – Bank Masking
Devices in densities of 64Mb–512Mb are comprised of four banks; densities of 1Gb and
higher are comprised of eight banks. Each bank can be configured independently
whether or not a SELF REFRESH operation will occur in that bank. One 8-bit mode register (accessible via the MRW command) is assigned to program the bank-masking status of each bank up to eight banks. For bank masking bit assignments, see the MR16
PASR Bank Mask (MA[7:0] = 010h) and MR16 Op-Code Bit Definitions tables.
The mask bit to the bank enables or disables a refresh operation of the entire memory
space within the bank. If a bank is masked using the bank mask register, a REFRESH op-
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SELF REFRESH Operation
eration to the entire bank is blocked and bank data retention is not guaranteed in self
refresh mode. To enable a REFRESH operation to a bank, the corresponding bank mask
bit must be programmed as “unmasked.” When a bank mask bit is unmasked, the array
space being refreshed within that bank is determined by the programmed status of the
segment mask bits.
Partial-Array Self Refresh – Segment Masking
Programming segment mask bits is similar to programming bank mask bits. For densities 1Gb and higher, eight segments are used for masking (see the MR17 PASR Segment
Mask (MA[7:0] = 011h) and MR17 PASR Segment Mask Definitions tables). A mode register is used for programming segment mask bits up to eight bits. For densities less than
1Gb, segment masking is not supported.
When the mask bit to an address range (represented as a segment) is programmed as
“masked,” a REFRESH operation to that segment is blocked. Conversely, when a segment mask bit to an address range is unmasked, refresh to that segment is enabled.
A segment masking scheme can be used in place of or in combination with a bank
masking scheme. Each segment mask bit setting is applied across all banks. For segment masking bit assignments, see the tables noted above.
Table 46: Bank and Segment Masking Example
Segment Mask (MR17) Bank 0 Bank 1 Bank 2 Bank 3 Bank 4 Bank 5 Bank 6 Bank 7
Bank Mask (MR16)
0
1
0
0
0
0
0
1
Segment 0
0
–
M
–
–
–
–
–
M
Segment 1
0
–
M
–
–
–
–
–
M
Segment 2
1
M
M
M
M
M
M
M
M
Segment 3
0
–
M
–
–
–
–
–
M
Segment 4
0
–
M
–
–
–
–
–
M
Segment 5
0
–
M
–
–
–
–
–
M
Segment 6
0
–
M
–
–
–
–
–
M
Segment 7
1
M
M
M
M
M
M
M
M
Note:
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1. This table provides values for an 8-bank device with REFRESH operations masked to
banks 1 and 7, and segments 2 and 7.
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MODE REGISTER READ
MODE REGISTER READ
The MODE REGISTER READ (MRR) command is used to read configuration and status
data from SDRAM mode registers. The MRR command is initiated with CS# LOW, CA0
LOW, CA1 LOW, CA2 LOW, and CA3 HIGH at the rising edge of the clock. The mode register is selected by CA1f–CA0f and CA9r–CA4r. The mode register contents are available
on the first data beat of DQ[7:0] after RL × tCK + tDQSCK + tDQSQ and following the rising edge of the clock where MRR is issued. Subsequent data beats contain valid but undefined content, except in the case of the DQ calibration function, where subsequent
data beats contain valid content as described in the Data Calibration Pattern Description table. All DQS are toggled for the duration of the mode register READ burst.
The MRR command has a burst length of four. MRR operation (consisting of the MRR
command and the corresponding data traffic) must not be interrupted. The MRR command period (tMRR) is two clock cycles.
Figure 48: MRR Timing – RL = 3, tMRR = 2
T0
CK#
CK
T1
T2
T3
T4
T5
T6
T7
T8
RL = 3
CA[9:0]
Register Register
A
A
Register Register
B
B
tMRR
CMD
MRR1
tMRR
=2
NOP2
MRR1
=2
NOP2
Valid
DQS#
DQS
DQ[7:0]3
DOUT A
DOUT B
DQ[MAX:8]
Transitioning data
Notes:
Undefined
1. MRRs to DQ calibration registers MR32 and MR40 are described in Data Calibration.
2. Only the NOP command is supported during tMRR.
3. Mode register data is valid only on DQ[7:0] on the first beat. Subsequent beats contain
valid but undefined data. DQ[MAX:8] contain valid but undefined data for the duration
of the MRR burst.
4. Minimum MRR to write latency is RL + RU(tDQSCKmax/tCK) + 4/2 + 1 - WL clock cycles.
5. Minimum MRR to MRW latency is RL + RU(tDQSCKmax/tCK) + 4/2 + 1 clock cycles.
READ bursts and WRITE bursts cannot be truncated by MRR. Following a READ command, the MRR command must not be issued before BL/2 clock cycles have completed.
Following a WRITE command, the MRR command must not be issued before WL + 1 +
BL/2 + RU(tWTR/tCK) clock cycles have completed. If a READ or WRITE burst is trunca-
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MODE REGISTER READ
ted with a BST command, the effective burst length of the truncated burst should be
used for the BL value.
Figure 49: READ to MRR Timing – RL = 3, tMRR = 2
T0
CK#
CK
CA[9:0]
T1
BL/21
Bank m
Col addr a
col addr a
T2
T3
Register
B
READ
T5
T6
T7
T8
RL = 3
Register
B
tMRR
CMD
T4
MRR
=2
NOP2
Valid
DQS#
DQS
DQ[7:0]
DOUT A0
DOUT A1
DOUT A2
DOUT A3
DQ[MAX:8]
DOUT A0
DOUT A1
DOUT A2
DOUT A3
DOUT B
Transitioning data
Notes:
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Undefined
1. The minimum number of clock cycles from the burst READ command to the MRR command is BL/2.
2. Only the NOP command is supported during tMRR.
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MODE REGISTER READ
Figure 50: Burst WRITE Followed by MRR – RL = 3, WL = 1, BL = 4
CK#
CK
T0
T1
T2
T3
T4
T5
T6
T7
WL = 3
CA[9:0]
RL = 3
Bank n
Col addr a
col addr a
Register
B
Register
B
tWTR
CMD
T8
Valid
WRITE
tMRR
MRR1
=2
NOP2
DQS#
DQS
DQ
DIN A0
DIN A1
DIN A2
DIN A3
Transitioning data
1. The minimum number of clock cycles from the burst WRITE command to the MRR command is [WL + 1 + BL/2 + RU(tWTR/tCK)].
2. Only the NOP command is supported during tMRR.
Notes:
Temperature Sensor
Mobile LPDDR2 devices feature a temperature sensor whose status can be read from
MR4. This sensor can be used to determine an appropriate refresh rate, determine
whether AC timing derating is required in the extended temperature range, and/or
monitor the operating temperature. Either the temperature sensor or the device operating temperature can be used to determine whether operating temperature requirements are being met (see Operating Temperature Range table).
Temperature sensor data can be read from MR4 using the mode register read protocol.
Upon exiting self-refresh or power-down, the device temperature status bits will be no
older than tTSI.
When using the temperature sensor, the actual device case temperature may be higher
than the operating temperature specification that applies for the standard or extended
temperature ranges (see table noted above). For example, T CASE could be above 85˚C
when MR4[2:0] equals 011b.
To ensure proper operation using the temperature sensor, applications must accommodate the parameters in the temperature sensor definitions table.
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MODE REGISTER READ
Table 47: Temperature Sensor Definitions and Operating Conditions
Parameter
Description
Symbol
Min/Max
Value
Unit
System temperature
gradient
Maximum temperature gradient experienced by the memory device at the temperature of interest over a range of 2˚C
TempGradient
MAX
System-dependent
˚C/s
MR4 READ interval
Time period between MR4 READs from the
system
ReadInterval
MAX
System-dependent
ms
Temperature sensor
interval
Maximum delay between internal updates
of MR4
tTSI
MAX
32
ms
System response
delay
Maximum response time from an MR4 READ
to the system response
SysRespDelay
MAX
System-dependent
ms
Device temperature
margin
Margin above maximum temperature to
support controller response
TempMargin
MAX
2
˚C
Mobile LPDDR2 devices accommodate the temperature margin between the point at
which the device temperature enters the extended temperature range and the point at
which the controller reconfigures the system accordingly. To determine the required
MR4 polling frequency, the system must use the maximum TempGradient and the maximum response time of the system according to the following equation:
TempGradient × (ReadInterval + tTSI + SysRespDelay) ≤ 2°C
For example, if TempGradient is 10˚C/s and the SysRespDelay is 1ms:
10°C × (ReadInterval + 32ms + 1ms) ≤ 2°C
s
In this case, ReadInterval must not exceed 167ms.
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MODE REGISTER READ
Figure 51: Temperature Sensor Timing
Temp
< (tTSI + ReadInterval + SysRespDelay)
Device
Temp
Margin
ie
Grad
Temp
2C
nt
MR4
Trip Level
tTSI
MR4 = 0x03
MR4 = 0x86
MR4 = 0x86
MR4 = 0x86
MR4 = 0x86
Time
Temperture sensor update
ReadInterval
Host MR4 READ
MRR MR4 = 0x03
SysRespDelay
MRR MR4 = 0x86
DQ Calibration
Mobile LPDDR2 devices feature a DQ calibration function that outputs one of two predefined system timing calibration patterns. For x16 devices, pattern A (MRR to MRR32),
and pattern B (MRR to MRR40), will return the specified pattern on DQ0 and DQ8; x32
devices return the specified pattern on DQ0, DQ8, DQ16, and DQ24.
For x16 devices, DQ[7:1] and DQ[15:9] drive the same information as DQ0 during the
MRR burst. For x32 devices, DQ[7:1], DQ[15:9], DQ[23:17], and DQ[31:25] drive the
same information as DQ0 during the MRR burst. MRR DQ calibration commands can
occur only in the idle state.
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MODE REGISTER READ
Figure 52: MR32 and MR40 DQ Calibration Timing – RL = 3, tMRR = 2
CK#
CK
T0
T1
T2
T3
T4
T5
T6
T7
T8
RL = 3
CA[9:0] Reg 32 Reg 32
Reg 40 Reg 40
tMRR
CMD
tMRR
=2
NOP1
MRR
MRR
=2
NOP
DQS#
DQS
Pattern A
Pattern B
DQ0
1
0
1
0
0
0
1
1
DQ[7:1]
1
0
1
0
0
0
1
1
x16
DQ8
1
0
1
0
0
0
1
1
DQ[15:9]
1
0
1
0
0
0
1
1
x32
DQ16
1
0
1
0
0
0
1
1
DQ[23:17]
1
0
1
0
0
0
1
1
DQ24
1
0
1
0
0
0
1
1
DQ[31:25]
1
0
1
0
0
0
1
1
Transitioning data
Note:
Optionally driven the same as DQ0 or 0b
1. Only the NOP command is supported during tMRR.
Table 48: Data Calibration Pattern Description
Pattern
MR#
Bit Time
0
Bit Time
1
Bit Time
2
Pattern A
MR32
1
0
1
0
Reads to MR32 return DQ calibration pattern A
Pattern B
MR40
0
0
1
1
Reads to MR40 return DQ calibration pattern B
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76
Bit Time
3
Description
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MODE REGISTER WRITE Command
MODE REGISTER WRITE Command
The MODE REGISTER WRITE (MRW) command is used to write configuration data to
the mode registers. The MRW command is initiated with CS# LOW, CA0 LOW, CA1 LOW,
CA2 LOW, and CA3 LOW at the rising edge of the clock. The mode register is selected by
CA1f–CA0f, CA9r–CA4r. The data to be written to the mode register is contained in
CA9f–CA2f. The MRW command period is defined by tMRW. MRWs to read-only registers have no impact on the functionality of the device.
MRW can only be issued when all banks are in the idle precharge state. One method of
ensuring that the banks are in this state is to issue a PRECHARGE ALL command.
Figure 53: MODE REGISTER WRITE Timing – RL = 3, tMRW = 5
CK#
CK
T0
T1
T2
Tx
Tx + 1
tMRW
CA[9:0]
CMD
Ty + 1
Ty + 2
tMRW
MR addr MR data
MRW
Ty1
Tx + 2
MR addr MR data
NOP2
NOP2
Notes:
NOP2
MRW
NOP2
Valid
1. At time Ty, the device is in the idle state.
2. Only the NOP command is supported during tMRW.
Table 49: Truth Table for MRR and MRW
Current State
All banks idle
Bank(s) active
Command
Intermediate State
Next State
MRR
Reading mode register, all banks idle
All banks idle
MRW
Writing mode register, all banks idle
All banks idle
MRW (RESET)
Resetting, device auto initialization
All banks idle
MRR
Reading mode register, bank(s) idle
Bank(s) active
MRW
Not allowed
Not allowed
MRW (RESET)
Not allowed
Not allowed
MRW RESET Command
The MRW RESET command brings the device to the device auto initialization (resetting) state in the power-on initialization sequence (see 2. RESET Command under Power-Up (page 26)). The MRW RESET command can be issued from the idle state. This
command resets all mode registers to their default values. Only the NOP command is
supported during tINIT4. After MRW RESET, boot timings must be observed until the
device initialization sequence is complete and the device is in the idle state. Array data
is undefined after the MRW RESET command has completed.
For MRW RESET timing, see Figure 13 (page 28).
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MODE REGISTER WRITE Command
MRW ZQ Calibration Commands
The MRW command is used to initiate a ZQ calibration command that calibrates output
driver impedance across process, temperature, and voltage. LPDDR2-S4 devices support ZQ calibration. To achieve tighter tolerances, proper ZQ calibration must be performed.
There are four ZQ calibration commands and related timings: tZQINIT, tZQRESET,
tZQCL, and tZQCS. tZQINIT is used for initialization calibration; tZQRESET is used for
resetting ZQ to the default output impedance; tZQCL is used for long calibration(s); and
tZQCS is used for short calibration(s). See the MR10 Calibration (MA[7:0] = 0Ah) table
for ZQ calibration command code definitions.
ZQINIT must be performed for LPDDR2 devices. ZQINIT provides an output impedance accuracy of ±15%. After initialization, the ZQ calibration long (ZQCL) can be used
to recalibrate the system to an output impedance accuracy of ±15%. A ZQ calibration
short (ZQCS) can be used periodically to compensate for temperature and voltage drift
in the system.
ZQRESET resets the output impedance calibration to a default accuracy of ±30% across
process, voltage, and temperature. This command is used to ensure output impedance
accuracy to ±30% when ZQCS and ZQCL commands are not used.
One ZQCS command can effectively correct at least 1.5% (ZQ correction) of output impedance errors within tZQCS for all speed bins, assuming the maximum sensitivities
specified in Table 80 and Table 81 (page 119) are met. The appropriate interval between
ZQCS commands can be determined using these tables and system-specific parameters.
Mobile LPDDR2 devices are subject to temperature drift rate (Tdriftrate) and voltage drift
rate (Vdriftrate) in various applications. To accommodate drift rates and calculate the
necessary interval between ZQCS commands, apply the following formula:
ZQcorrection
(Tsens × Tdriftrate ) + (Vsens × Vdriftrate )
Where T sens = MAX (dRONdT) and V sens = MAX (dRONdV) define temperature and voltage sensitivities.
For example, if T sens = 0.75%/˚C, V sens = 0.20%/mV, T driftrate = 1˚C/sec, and V driftrate =
15 mV/sec, then the interval between ZQCS commands is calculated as:
1.5
= 0.4s
(0.75 × 1) + (0.20 × 15)
A ZQ calibration command can only be issued when the device is in the idle state with
all banks precharged.
No other activities can be performed on the data bus during calibration periods
(tZQINIT, tZQCL, or tZQCS). The quiet time on the data bus helps to accurately calibrate
output impedance. There is no required quiet time after the ZQRESET command. If
multiple devices share a single ZQ resistor, only one device can be calibrating at any given time. After calibration is complete, the ZQ ball circuitry is disabled to reduce power
consumption.
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MODE REGISTER WRITE Command
In systems sharing a ZQ resistor between devices, the controller must prevent tZQINIT,
and tZQCL overlap between the devices. ZQRESET overlap is acceptable. If the
ZQ resistor is absent from the system, ZQ must be connected to V DDCA. In this situation,
the device must ignore ZQ calibration commands and the device will use the default
calibration settings.
tZQCS,
Figure 54: ZQ Timings
CK#
CK
CA[9:0]
T0
T1
T2
T3
T4
T5
Tx
Tx + 1
Tx + 2
MR addr MR data
ZQINIT
tZQINIT
CMD
MRW
NOP
NOP
NOP
NOP
NOP
Valid
NOP
NOP
Valid
NOP
NOP
Valid
NOP
NOP
Valid
ZQCS
tZQCS
CMD
MRW
NOP
NOP
NOP
ZQCL
tZQCL
CMD
MRW
NOP
NOP
NOP
ZQRESET
tZQRESET
CMD
MRW
NOP
Notes:
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NOP
NOP
1. Only the NOP command is supported during ZQ calibrations.
2. CKE must be registered HIGH continuously during the calibration period.
3. All devices connected to the DQ bus should be High-Z during the calibration process.
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Power-Down
ZQ External Resistor Value, Tolerance, and Capacitive Loading
To use the ZQ calibration function, a 240 ohm (±1% tolerance) external resistor must be
connected between the ZQ pin and ground. A single resistor can be used for each device
or one resistor can be shared between multiple devices if the ZQ calibration timings for
each device do not overlap. The total capacitive loading on the ZQ pin must be limited
(see the Input/Output Capacitance table).
Power-Down
Power-down is entered synchronously when CKE is registered LOW and CS# is HIGH at
the rising edge of clock. A NOP command must be driven in the clock cycle following
power-down entry. CKE must not go LOW while MRR, MRW, READ, or WRITE operations are in progress. CKE can go LOW while any other operations such as ACTIVATE,
PRECHARGE, auto precharge, or REFRESH are in progress, but the power-down IDD
specification will not be applied until such operations are complete.
If power-down occurs when all banks are idle, this mode is referred to as idle powerdown; if power-down occurs when there is a row 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. In power-down mode, CKE must be held LOW; all other input signals are “Don’t
Care.” CKE LOW must be maintained until tCKE is satisfied. V REFCA must be maintained
at a valid level during power-down.
VDDQ can be turned off during power-down. If V DDQ is turned off, V REFDQ must also be
turned off. Prior to exiting power-down, both V DDQ and V REFDQ must be within their respective minimum/maximum operating ranges (see AC and DC Operating Conditions).
No refresh operations are performed in power-down mode. The maximum duration in
power-down mode is only limited by the refresh requirements outlined in REFRESH
Command.
The power-down state is exited when CKE is registered HIGH. The controller must drive
CS# HIGH in conjunction with CKE HIGH when exiting the power-down state. CKE
HIGH must be maintained until tCKE is satisfied. A valid, executable command can be
applied with power-down exit latency tXP after CKE goes HIGH. Power-down exit latency is defined in the AC Timing section.
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Power-Down
Figure 55: Power-Down Entry and Exit Timing
2 tCK (MIN)
CK/CK#
Input clock frequency can be changed
1
or the input clock can be stopped during power-down.
tIHCKE
tIHCKE
tCKE(MIN)
CKE
tISCKE
tISCKE
CS#
tCKE(MIN)
CMD
tXP (MIN)
Exit
PD
Valid Enter NOP
PD
Enter power-down mode
NOP NOP Valid
Exit power-down mode
Don’t Care
Note:
1. Input clock frequency can be changed or the input clock stopped during power-down,
provided that the clock frequency is between the minimum and maximum specified frequencies for the speed grade in use, and that prior to power-down exit, a minimum of
two stable clocks complete.
Figure 56: CKE Intensive Environment
CK#
CK
tCKE
tCKE
tCKE
tCKE
CKE
Figure 57: REFRESH-to-REFRESH Timing in CKE Intensive Environments
CK#
CK
tCKE
CKE
tCKE
tXP
CMD
tREFI
REFRESH
Note:
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tCKE
tCKE
tXP
REFRESH
1. The pattern shown can repeat over an extended period of time. With this pattern, all
AC and DC timing and voltage specifications with temperature and voltage drift are ensured.
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Power-Down
Figure 58: READ to Power-Down Entry
BL = 4
T0
T1
T2
Tx
Tx + 1
Tx + 2
Tx + 3
Tx + 4
Tx + 5
Tx + 6
Tx + 7
Tx + 8
Tx + 9
Tx + 5
Tx + 6
Tx + 7
Tx + 8
Tx + 9
CK#
CK
RL
tISCKE
CKE1, 2
CMD
READ
DQ
DOUT DOUT DOUT DOUT
DQS#
DQS
BL = 8
T0
T1
T2
Tx
Tx + 1
Tx + 2
Tx + 3
Tx + 4
CK#
CK
RL
tISCKE
CKE1, 2
CMD
READ
DQ
DOUT DOUT DOUT DOUT DOUT DOUT DOUT DOUT
DQS#
DQS
Notes:
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1. CKE must be held HIGH until the end of the burst operation.
2. CKE can be registered LOW at (RL + RU(tDQSCK(MAX)/tCK) + BL/2 + 1) clock cycles after
the clock on which the READ command is registered.
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2Gb: x16, x32, x64 Automotive LPDDR2 SDRAM
Power-Down
Figure 59: READ with Auto Precharge to Power-Down Entry
BL = 4
T0
T1
T2
CK#
CK
Tx
Tx + 1
Tx + 2
Tx + 3
Tx + 4
BL/23
Tx + 5
Tx + 6
Tx + 7
Tx + 8
Tx + 9
Tx + 6
Tx + 7
Tx + 8
Tx + 9
tISCKE
RL
CKE1, 2
CMD
PRE4
READ w/AP
DQ
DOUT DOUT DOUT DOUT
DQS#
DQS
BL = 8
T0
T1
T2
CK#
CK
Tx
Tx + 1
Tx + 2
Tx + 3
Tx + 4
Tx + 5
RL
tISCKE
BL/23
CKE1, 2
CMD
READ w/AP
DQ
PRE4
DOUT DOUT DOUT DOUT DOUT DOUT DOUT DOUT
DQS#
DQS
Notes:
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1. CKE must be held HIGH until the end of the burst operation.
2. CKE can be registered LOW at (RL + RU(tDQSCK/tCK)+ BL/2 + 1) clock cycles after the
clock on which the READ command is registered.
3. BL/2 with tRTP = 7.5ns and tRAS (MIN) is satisfied.
4. Start internal PRECHARGE.
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2Gb: x16, x32, x64 Automotive LPDDR2 SDRAM
Power-Down
Figure 60: WRITE to Power-Down Entry
BL = 4
T0
T1
CK#
CK
Tm
Tm + 1
Tm + 2
Tm + 3
Tx
Tx + 1
WL
Tx + 2
Tx + 3
Tx + 4
Tx + 5
Tx + 6
Tx
Tx + 1
Tx + 2
Tx + 3
Tx + 4
tISCKE
BL/2
CKE1
tWR
CMD
WRITE
DQ
DIN
DIN
DIN
DIN
DQS#
DQS
BL = 8
T0
CK#
CK
T1
Tm
WL
Tm +m1
Tm + 2
Tm + 3
Tm + 4
Tm + 5
tISCKE
BL/2
CKE1
tWR
CMD
WRITE
DQ
DIN
DIN
DIN
DIN
DIN
DIN
DIN
DIN
DQS#
DQS
Note:
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1. CKE can be registered LOW at (WL + 1 + BL/2 + RU(tWR/tCK)) clock cycles after the clock
on which the WRITE command is registered.
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2Gb: x16, x32, x64 Automotive LPDDR2 SDRAM
Power-Down
Figure 61: WRITE with Auto Precharge to Power-Down Entry
BL = 4
T0
T1
CK#
CK
Tm
Tm + 1
Tm + 2
Tm + 3
Tx
Tx + 1
WL
Tx + 2
Tx + 3
Tx + 4
Tx + 5
Tx + 6
Tx + 1
Tx + 2
Tx + 3
Tx + 4
tISCKE
BL/2
CKE1
tWR
CMD
PRE2
WRITE w/AP
DQ
DIN
DIN
DIN
DIN
DQS#
DQS
BL = 8
T0
CK#
CK
T1
Tm
Tm + 1
Tm + 2
Tm + 3
Tm + 4
Tm + 5
Tx
WL
tISCKE
BL/2
CKE1
tWR
CMD
PRE2
WRITE w/AP
DQ
DIN
DIN
DIN
DIN
DIN
DIN
DIN
DIN
DQS#
DQS
Notes:
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1. CKE can be registered LOW at (WL + 1 + BL/2 + RU(tWR/tCK + 1) clock cycles after the
WRITE command is registered.
2. Start internal PRECHARGE.
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2Gb: x16, x32, x64 Automotive LPDDR2 SDRAM
Power-Down
Figure 62: REFRESH Command to Power-Down Entry
T0
T1
T2
T3
T4
T5
T6
T7
T8
T9
T10
T11
CK#
CK
tCKE
tIHCKE
CKE1
tISCKE
tCKE
CMD
REFRESH
1. CKE can go LOW tIHCKE after the clock on which the REFRESH command is registered.
Note:
Figure 63: ACTIVATE Command to Power-Down Entry
T0
T1
T2
T3
T4
T5
T6
T7
T8
T9
T10
T11
CK#
CK
tCKE
tIHCKE
CKE1
tISCKE
tCKE
CMD
ACTIVATE
1. CKE can go LOW at tIHCKE after the clock on which the ACTIVATE command is registered.
Note:
Figure 64: PRECHARGE Command to Power-Down Entry
T0
T1
T2
T3
T4
T5
T6
T7
T8
T9
T10
T11
CK#
CK
tCKE
CKE1
tIHCKE
tISCKE
tCKE
CMD
PRE
Note:
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1. CKE can go LOW tIHCKE after the clock on which the PRECHARGE command is registered.
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2Gb: x16, x32, x64 Automotive LPDDR2 SDRAM
Deep Power-Down
Figure 65: MRR Command to Power-Down Entry
T0
T1
T2
Tx
Tx + 1
Tx + 2
Tx + 3
Tx + 4
Tx + 5
Tx + 6
Tx + 7
Tx + 8
Tx + 9
CK#
CK
tISCKE
RL
CKE1
CMD
MRR
DQ
DOUT DOUT DOUT DOUT
DQS#
DQS
1. CKE can be registered LOW at (RL + RU(tDQSCK/tCK)+ BL/2 + 1) clock cycles after the
clock on which the MRR command is registered.
Note:
Figure 66: MRW Command to Power-Down Entry
T0
T1
T2
T3
T4
T5
T6
T7
T8
T9
T10
T11
CK#
CK
tISCKE
CKE1
tMRW
CMD
MRW
Note:
1. CKE can be registered LOW tMRW after the clock on which the MRW command is registered.
Deep Power-Down
Deep power-down (DPD) is entered when CKE is registered LOW with CS# LOW, CA0
HIGH, CA1 HIGH, and CA2 LOW at the rising edge of the clock. The NOP command
must be driven in the clock cycle following power-down entry. CKE must not go LOW
while MRR or MRW operations are in progress. CKE can go LOW while other operations
such as ACTIVATE, auto precharge, PRECHARGE, or REFRESH are in progress, however,
deep power-down IDD specifications will not be applied until those operations complete. The contents of the array will be lost upon entering DPD mode.
In DPD mode, all input buffers except CKE, all output buffers, and the power supply to
internal circuitry are disabled within the device. V REFDQ can be at any level between 0
and V DDQ, and V REFCA can be at any level between 0 and V DDCA during DPD. All power
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Input Clock Frequency Changes and Stop Events
supplies (including V REF) must be within the specified limits prior to exiting DPD (see
AC and DC Operating Conditions).
To exit DPD, CKE must be HIGH, tISCKE must be complete, and the clock must be stable. To resume operation, the device must be fully reinitialized using the power-up initialization sequence.
Figure 67: Deep Power-Down Entry and Exit Timing
CK/CK#
Input clock frequency can be changed
or the input clock can be stopped during DPD.
tIHCKE
2 tCK (MIN)
tINIT31, 2
CKE
tISCKE
tISCKE
CS#
tDPD
tRP
CMD
Exit
DPD
NOP Enter NOP
DPD
Enter DPD mode
NOP
RESET
Exit DPD mode
Don’t Care
Notes:
1. The initialization sequence can start at any time after Tx + 1.
2. tINIT3 and Tx + 1 refer to timings in the initialization sequence. For details, see Mode
Register Definition.
Input Clock Frequency Changes and Stop Events
Input Clock Frequency Changes and Clock Stop with CKE LOW
During CKE LOW, Mobile LPDDR2 devices support input clock frequency changes and
clock stop under the following conditions:
• Refresh requirements are met
• Only REFab or REFpb commands can be in process
• Any ACTIVATE or PRECHARGE commands have completed prior to changing the frequency
• Related timing conditions,tRCD and tRP, have been met prior to changing the frequency
• The initial clock frequency must be maintained for a minimum of two clock cycles after CKE goes LOW
• The clock satisfies tCH(abs) and tCL(abs) for a minimum of two clock cycles prior to
CKE going HIGH
For input clock frequency changes, tCK(MIN) and tCK(MAX) must be met for each clock
cycle.
After the input clock frequency is changed and CKE is held HIGH, additional MRW
commands may be required to set the WR, RL, etc. These settings may require adjustment to meet minimum timing requirements at the target clock frequency.
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2Gb: x16, x32, x64 Automotive LPDDR2 SDRAM
NO OPERATION Command
For clock stop, CK is held LOW and CK# is held HIGH.
Input Clock Frequency Changes and Clock Stop with CKE HIGH
During CKE HIGH, LPDDR2 devices support input clock frequency changes and clock
stop under the following conditions:
• REFRESH requirements are met
• Any ACTIVATE, READ, WRITE, PRECHARGE, MRW, or MRR commands must have
completed, including any associated data bursts, prior to changing the frequency
• Related timing conditions, tRCD, tWR, tWRA, tRP, tMRW, and tMRR, etc., are met
• CS# must be held HIGH
• Only REFab or REFpb commands can be in process
The device is ready for normal operation after the clock satisfies tCH(abs) and tCL(abs)
for a minimum of 2 × tCK + tXP.
For input clock frequency changes, tCK(MIN) and tCK(MAX) must be met for each clock
cycle.
After the input clock frequency is changed, additional MRW commands may be required to set the WR, RL, etc. These settings may require adjustment to meet minimum
timing requirements at the target clock frequency.
For clock stop, CK is held LOW and CK# is held HIGH.
NO OPERATION Command
The NO OPERATION (NOP) command prevents the device from registering any unwanted commands issued between operations. A NOP command can only be issued at
clock cycle N when the CKE level is constant for clock cycle N-1 and clock cycle N. The
NOP command has two possible encodings: CS# HIGH at the clock rising edge N; and
CS# LOW with CA0, CA1, CA2 HIGH at the clock rising edge N.
The NOP command will not terminate a previous operation that is still in process, such
as a READ burst or WRITE burst cycle.
Simplified Bus Interface State Diagram
The state diagram (see Figure 68 (page 90)) provides a simplified illustration of the bus
interface, supported state transitions, and the commands that control them. For a complete description of device behavior, use the information provided in the state diagram
with the truth tables and timing specifications.
The truth tables describe device behavior and applicable restrictions when considering
the actual state of all banks.
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2Gb: x16, x32, x64 Automotive LPDDR2 SDRAM
NO OPERATION Command
Figure 68: Simplified Bus Interface State Diagram
Power
applied
Deep
power-down
DPDX
Power-on
RE
Automatic sequence
SE
MRR
Resetting
MR reading
Command sequence
T
Self
refreshing
Resetting
DPD
T
MRR
REF
Idle1
Refreshing
X
M
PD
RW
Idle
MR reading
X
SR
SE
EF
RE
X
PD
Resetting
power-down
SR
EF
PD
PD
Idle
power-down
MR writing
ACT
Active
power-down
Active
MR reading
PD
X
PD
R
MR
Active
BST
W
Writing
RA
RD
Reading
A
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WR
RD
Note:
BST
RD
WR
PR = PRECHARGE
PRA = PRECHARGE ALL
ACT = ACTIVATE
WR(A) = WRITE (with auto precharge)
RD(A) = READ (with auto precharge)
BST = BURST TERMINATE
RESET = RESET is achieved through
MRW command
MRW = MODE REGISTER WRITE
MRR = MODE REGISTER READ
PD = enter power-down
PDX = exit power-down
SREF = enter self refresh
SREFX = exit self refresh
DPD = enter deep power-down
DPDX = exit deep power-down
REF = REFRESH
PR
PR, PRA
WRA
RDA
Writing
with
auto precharge
Reading
with
auto precharge
Precharging
1. All banks are precharged in the idle state.
90
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2Gb: x16, x32, x64 Automotive LPDDR2 SDRAM
Truth Tables
Truth Tables
Truth tables provide complementary information to the state diagram. They also clarify
device behavior and applicable restrictions when considering the actual state of the
banks.
Unspecified operations and timings are illegal. To ensure proper operation after an illegal event, the device must be powered down and then restarted using the specified initialization sequence before normal operation can continue.
Table 50: Command Truth Table
Notes 1–11 apply to all parameters conditions
Command Pins
CA Pins
CKE
Command
CA1
CA2
CA3
CA4
CA5
CA6
CA7
CA8
CA9
L
L
L
L
MA0
MA1
MA2
MA3
MA4
MA5
X
MA6
MA7
OP0
OP1
OP2
OP3
OP4
OP5
OP6
OP7
H
L
L
L
L
H
MA0
MA1
MA2
MA3
MA4
MA5
H
H
X
MA6
H
H
L
L
H
H
X
H
H
L
H
H
X
Enter self
refresh
H
L
L
X
L
X
ACTIVATE
(bank)
H
H
L
L
H
R8
R9
R10
R11
R12
BA0
BA1
BA2
H
H
X
R0
R1
R2
R3
R4
R5
R6
R7
R13
R14
WRITE (bank)
H
H
L
H
L
L
RFU
RFU
C1
C2
BA0
BA1
BA2
H
H
X
AP
C3
C4
C5
C6
C7
C8
C9
C10
C11
H
H
L
H
L
H
RFU
RFU
C1
C2
BA0
BA1
BA2
H
H
X
AP
C3
C4
C5
C6
C7
C8
C9
C10
C11
PRECHARGE
(bank)
H
H
L
H
H
L
H
AB
X
X
BA0
BA1
BA2
H
H
X
BST
H
H
L
H
H
X
H
L
L
X
L
X
H
H
L
H
H
X
L
L
L
L
L
X
MRW
MRR
REFRESH
(per bank)
REFRESH
(all banks)
READ (bank)
Enter DPD
NOP
Maintain PD,
SREF, DPD,
(NOP)
CK(n-1)
CK(n)
H
H
L
H
H
H
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CS# CA0
MA7
L
CK
Edge
X
H
L
X
X
L
L
H
H
X
X
L
L
H
X
X
X
H
H
L
L
X
X
H
H
L
X
X
H
H
H
X
X
H
H
H
X
X
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2Gb: x16, x32, x64 Automotive LPDDR2 SDRAM
Truth Tables
Table 50: Command Truth Table (Continued)
Notes 1–11 apply to all parameters conditions
Command Pins
CA Pins
CKE
Command
CK(n-1)
CK(n)
H
H
H
X
H
H
X
X
Maintain PD,
SREF, DPD,
(NOP)
L
L
H
X
L
L
X
X
Enter powerdown
H
L
H
X
X
L
X
X
Exit PD, SREF,
DPD
L
H
H
X
X
H
X
X
NOP
Notes:
CS# CA0
CA1
CA2
CA3
CA4
CA5
CA6
CA7
CA8
CA9
CK
Edge
1. All commands are defined by the current state of CS#, CA0, CA1, CA2, CA3, and CKE at
the rising edge of the clock.
2. Bank addresses (BA) determine which bank will be operated upon.
3. AP HIGH during a READ or WRITE command indicates that an auto precharge will occur
to the bank associated with the READ or WRITE command.
4. X indicates a “Don’t Care” state, with a defined logic level, either HIGH (H) or LOW (L).
5. Self refresh exit and DPD exit are asynchronous.
6. VREF must be between 0 and VDDQ during self refresh and DPD operation.
7. CAxr refers to command/address bit “x” on the rising edge of clock.
8. CAxf refers to command/address bit “x” on the falling edge of clock.
9. CS# and CKE are sampled on the rising edge of the clock.
10. Per-bank refresh is only supported in devices with eight banks.
11. The least-significant column address C0 is not transmitted on the CA bus, and is inferred
to be zero.
Table 51: CKE Truth Table
Notes 1–5 apply to all parameters and conditions; L = LOW, H = HIGH, X = “Don’t Care”
Command
Current State
CKEn-1
CKEn
CS#
n
Operation n
Next State
Active
power-down
Active
power-down
Idle power-down
Resetting idle
power-down
L
L
X
X
L
H
H
NOP
L
L
X
X
L
H
H
NOP
L
L
X
X
L
H
H
NOP
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Maintain active power-down
Exit active power-down
Maintain idle power-down
Exit idle power-down
Maintain resetting power-down
Exit resetting power-down
92
Active
Notes
6, 7
Idle
power-down
Idle
6, 7
Resetting
power-down
Idle or resetting 6, 7, 8
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2Gb: x16, x32, x64 Automotive LPDDR2 SDRAM
Truth Tables
Table 51: CKE Truth Table (Continued)
Notes 1–5 apply to all parameters and conditions; L = LOW, H = HIGH, X = “Don’t Care”
Command
Current State
CKEn-1
CKEn
CS#
n
Operation n
Next State
Deep powerdown
Deep
power-down
Self refresh
L
L
X
X
L
H
H
NOP
Maintain deep power-down
Exit deep power-down
Power-on
L
L
X
X
L
H
H
NOP
Exit self refresh
Bank(s) active
H
L
H
NOP
Enter active power-down
Active
power-down
All banks idle
H
L
H
NOP
Enter idle power-down
Idle
power-down
H
L
L
Enter self
refresh
H
L
L
DPD
Enter deep power-down
Deep
power-down
Resetting
H
L
H
NOP
Enter resetting power-down
Resetting
power-down
Other states
H
H
Notes:
Maintain self refresh
Notes
9
Self refresh
Idle
Enter self refresh
10, 11
Self refresh
Refer to the command truth table
1. Current state = the state of the device immediately prior to the clock rising edge n.
2. All states and sequences not shown are illegal or reserved unless explicitly described
elsewhere in this document.
3. CKEn = the logic state of CKE at clock rising edge n; CKEn-1 was the state of CKE at the
previous clock edge.
4. CS#= the logic state of CS# at the clock rising edge n.
5. Command n = the command registered at clock edge n, and operation n is a result of
command n.
6. Power-down exit time (tXP) must elapse before any command other than NOP is issued.
7. The clock must toggle at least twice prior to the tXP period.
8. Upon exiting the resetting power-down state, the device will return to the idle state if
tINIT5 has expired.
9. The DPD exit procedure must be followed as described in Deep Power Down.
10. Self refresh exit time (tXSR) must elapse before any command other than NOP is issued.
11. The clock must toggle at least twice prior to the tXSR time.
Table 52: Current State Bank n to Command to Bank n Truth Table
Notes 1–5 apply to all parameters and conditions
Current State
Command
Any
NOP
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Operation
Next State
Continue previous operation
93
Notes
Current state
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2Gb: x16, x32, x64 Automotive LPDDR2 SDRAM
Truth Tables
Table 52: Current State Bank n to Command to Bank n Truth Table (Continued)
Notes 1–5 apply to all parameters and conditions
Current State
Command
Idle
Row active
ACTIVATE
Select and activate row
Notes
Active
Begin to refresh
Refreshing (per bank)
6
Refresh (all banks)
Begin to refresh
Refreshing (all banks)
7
MR writing
7
MRW
Load value to mode register
MRR
Read value from mode register
Idle, MR reading
RESET
Begin device auto initialization
Resetting
7, 8
9, 10
PRECHARGE
Deactivate row(s) in bank or banks
Precharging
READ
Select column and start read burst
Reading
WRITE
Select column and start write burst
Writing
Read value from mode register
PRECHARGE
Deactivate row(s) in bank or banks
Active MR reading
Precharging
9
READ
Select column and start new read burst
Reading
11, 12
WRITE
Select column and start write burst
Writing
11, 12, 13
Active
14
BST
Writing
Next State
Refresh (per bank)
MRR
Reading
Operation
Read burst terminate
WRITE
Select column and start new write burst
Writing
11, 12
READ
Select column and start read burst
Reading
11, 12, 15
Active
14
7, 9
BST
Write burst terminate
Power-on
MRW RESET
Begin device auto initialization
Resetting
Resetting
MRR
Read value from mode register
Resetting MR reading
Notes:
1. Values in this table apply when both CKEn -1 and CKEn are HIGH, and after tXSR or tXP
has been met, if the previous state was power-down.
2. All states and sequences not shown are illegal or reserved.
3. Current state definitions:
Idle: The bank or banks have been precharged, and tRP has been met.
Active: A row in the bank has been activated, and tRCD has been met. No data bursts or
accesses and no register accesses are in progress.
Reading: A READ burst has been initiated with auto precharge disabled and has not yet
terminated or been terminated.
Writing: A WRITE burst has been initiated with auto precharge disabled and has not yet
terminated or been terminated.
4. The states listed below must not be interrupted by a command issued to the same bank.
NOP commands or supported commands to the other bank must be issued on any clock
edge occurring during these states. Supported commands to the other banks are determined by that bank’s current state, and the definitions given in the following table.
Precharge: Starts with registration of a PRECHARGE command and ends when tRP is
met. After tRP is met, the bank is in the idle state.
Row activate: Starts with registration of an ACTIVATE command and ends when tRCD is
met. After tRCD is met, the bank is in the active state.
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Truth Tables
READ with AP enabled: Starts with registration of a READ command with auto precharge enabled and ends when tRP is met. After tRP is met, the bank is in the idle state.
WRITE with AP enabled: Starts with registration of a WRITE command with auto precharge enabled and ends when tRP is met. After tRP is met, the bank is in the idle state.
5. The states listed below must not be interrupted by any executable command. NOP commands must be applied to each rising clock edge during these states.
Refresh (per bank): Starts with registration of a REFRESH (per bank) command and ends
when tRFCpb is met. After tRFCpb is met, the bank is in the idle state.
Refresh (all banks): Starts with registration of a REFRESH (all banks) command and ends
when tRFCab is met. After tRFCab is met, the device is in the all banks idle state.
Idle MR reading: Starts with registration of the MRR command and ends when tMRR is
met. After tMRR is met, the device is in the all banks idle state.
Resetting MR reading: Starts with registration of the MRR command and ends when
tMRR is met. After tMRR is met, the device is in the all banks idle state.
Active MR reading: Starts with registration of the MRR command and ends when tMRR
is met. After tMRR is met, the bank is in the active state.
MR writing: Starts with registration of the MRW command and ends when tMRW is met.
After tMRW is met, the device is in the all banks idle state.
6.
7.
8.
9.
10.
11.
12.
13.
14.
15.
Precharging all: Starts with registration of a PRECHARGE ALL command and ends when
tRP is met. After tRP is met, the device is in the all banks idle state.
Bank-specific; requires that the bank is idle and no bursts are in progress.
Not bank-specific; requires that all banks are idle and no bursts are in progress.
Not bank-specific.
This command may or may not be bank specific. If all banks are being precharged, they
must be in a valid state for precharging.
If a PRECHARGE command is issued to a bank in the idle state, tRP still applies.
A command other than NOP should not be issued to the same bank while a burst READ
or burst WRITE with auto precharge is enabled.
The new READ or WRITE command could be auto precharge enabled or auto precharge
disabled.
A WRITE command can be issued after the completion of the READ burst; otherwise, a
BST must be issued to end the READ prior to asserting a WRITE command.
Not bank-specific. The BST command affects the most recent READ/WRITE burst started
by the most recent READ/WRITE command, regardless of bank.
A READ command can be issued after completion of the WRITE burst; otherwise, a BST
must be used to end the WRITE prior to asserting another READ command.
Table 53: Current State Bank n to Command to Bank m Truth Table
Notes 1–6 apply to all parameters and conditions
Current State
of Bank n
Command to Bank m
Operation
Next State for Bank m
Any
NOP
Continue previous operation
Idle
Any
Any command supported to bank m
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95
Notes
Current state of bank m
–
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Truth Tables
Table 53: Current State Bank n to Command to Bank m Truth Table (Continued)
Notes 1–6 apply to all parameters and conditions
Current State
of Bank n
Command to Bank m
Row activating,
active, or precharging
ACTIVATE
Writing
(auto precharge
disabled)
Reading with
auto precharge
Writing with
auto precharge
Select and activate row in bank m
Next State for Bank m
Notes
Active
8
READ
Select column and start READ burst
from bank m
Reading
9
WRITE
Select column and start WRITE burst to
bank m
Writing
9
Precharging
10
Idle MR reading or active
MR reading
11, 12, 13
Active
7
PRECHARGE
Reading
(auto precharge
disabled)
Operation
Deactivate row(s) in bank or banks
MRR
READ value from mode register
BST
READ or WRITE burst terminates an ongoing READ/WRITE from/to bank m
READ
Select column and start READ burst
from bank m
Reading
9
WRITE
Select column and start WRITE burst to
bank m
Writing
9, 14
ACTIVATE
Select and activate row in bank m
Active
PRECHARGE
Deactivate row(s) in bank or banks
Precharging
10
READ
Select column and start READ burst
from bank m
Reading
9, 15
WRITE
Select column and start WRITE burst to
bank m
Writing
9
ACTIVATE
Select and activate row in bank m
Active
PRECHARGE
Deactivate row(s) in bank or banks
Precharging
10
READ
Select column and start READ burst
from bank m
Reading
9, 16
WRITE
Select column and start WRITE burst to
bank m
Writing
9, 14, 16
ACTIVATE
Select and activate row in bank m
Active
PRECHARGE
Deactivate row(s) in bank or banks
Precharging
10
READ
Select column and start READ burst
from bank m
Reading
9, 15, 16
WRITE
Select column and start WRITE burst to
bank m
Writing
9, 16
ACTIVATE
Select and activate row in bank m
Active
PRECHARGE
Deactivate row(s) in bank or banks
Precharging
10
Power-on
MRW RESET
Begin device auto initialization
Resetting
17, 18
Resetting
MRR
Read value from mode register
Resetting MR reading
Notes:
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1. This table applies when: the previous state was self refresh or power-down; after tXSR
or tXP has been met; and both CKEn -1 and CKEn are HIGH.
2. All states and sequences not shown are illegal or reserved.
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Truth Tables
3. Current state definitions:
Idle: The bank has been precharged and tRP has been met.
Active: A row in the bank has been activated, tRCD has been met, no data bursts or accesses and no register accesses are in progress.
Read: A READ burst has been initiated with auto precharge disabled and the READ has
not yet terminated or been terminated.
Write: A WRITE burst has been initiated with auto precharge disabled and the WRITE
has not yet terminated or been terminated.
4. Refresh, self refresh, and MRW commands can only be issued when all banks are idle.
5. A BST command cannot be issued to another bank; it applies only to the bank represented by the current state.
6. The states listed below must not be interrupted by any executable command. NOP commands must be applied during each clock cycle while in these states:
Idle MRR: Starts with registration of the MRR command and ends when tMRR has been
met. After tMRR is met, the device is in the all banks idle state.
Reset MRR: Starts with registration of the MRR command and ends when tMRR has been
met. After tMRR is met, the device is in the all banks idle state.
Active MRR: Starts with registration of the MRR command and ends when tMRR has
been met. After tMRR is met, the bank is in the active state.
7.
8.
9.
10.
11.
12.
13.
14.
15.
16.
17.
18.
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MRW: Starts with registration of the MRW command and ends when tMRW has been
met. After tMRW is met, the device is in the all banks idle state.
BST is supported only if a READ or WRITE burst is ongoing.
tRRD must be met between the ACTIVATE command to bank n and any subsequent
ACTIVATE command to bank m.
READs or WRITEs listed in the command column include READs and WRITEs with or
without auto precharge enabled.
This command may or may not be bank-specific. If all banks are being precharged, they
must be in a valid state for precharging.
MRR is supported in the row-activating state.
MRR is supported in the precharging state.
The next state for bank m depends on the current state of bank m (idle, row-activating,
precharging, or active).
A WRITE command can be issued after the completion of the READ burst; otherwise a
BST must be issued to end the READ prior to asserting a WRITE command.
A READ command can be issued after the completion of the WRITE burst; otherwise, a
BST must be issued to end the WRITE prior to asserting another READ command.
A READ with auto precharge enabled or a WRITE with auto precharge enabled can be
followed by any valid command to other banks provided that the timing restrictions in
the PRECHARGE and Auto Precharge Clarification table are met.
Not bank-specific; requires that all banks are idle and no bursts are in progress.
RESET command is achieved through MODE REGISTER WRITE command.
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Truth Tables
Table 54: DM Truth Table
Functional Name
Note:
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DM
DQ
Notes
Write enable
L
Valid
1
Write inhibit
H
X
1
1. Used to mask write data, and is provided simultaneously with the corresponding input
data.
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Electrical Specifications
Electrical Specifications
Absolute Maximum Ratings
Stresses greater than those listed below 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 outside those indicated in the operational sections of this document is not
implied. Exposure to absolute maximum rating conditions for extended periods may
adversely affect reliability.
Table 55: Absolute Maximum DC Ratings
Parameter
Symbol
Min
Max
Unit
Notes
VDD1 supply voltage relative to VSS
VDD1
–0.4
+2.3
V
1
VDD2 supply voltage relative to VSS
VDD2 (1.2V)
–0.4
+1.6
V
1
VDDCA supply voltage relative to VSSCA
VDDCA
–0.4
+1.6
V
1, 2
VDDQ supply voltage relative to VSSQ
VDDQ
–0.4
+1.6
V
1, 3
VIN, VOUT
–0.4
+1.6
V
TSTG
–55
+125
˚C
Voltage on any ball relative to VSS
Storage temperature
Notes:
1.
2.
3.
4.
4
See 1. Voltage Ramp under Power-Up (page 26).
VREFCA 0.6 ≤ VDDCA; however, VREFCA may be ≥ VDDCA provided that VREFCA ≤ 300mV.
VREFDQ 0.6 ≤ VDDQ; however, VREFDQ may be ≥ VDDQ provided that VREFDQ ≤ 300mV.
Storage temperature is the case surface temperature on the center/top side of the device. For measurement conditions, refer to the JESD51-2 standard.
Input/Output Capacitance
Table 56: Input/Output Capacitance
Note 1 applies to all parameters and conditions
LPDDR2 1066-466
Parameter
LPDDR2 400-200
Symbol
MIN
MAX
MIN
MAX
Unit
Notes
Input capacitance, CK and CK#
CCK
1.0
2.0
1.0
2.0
pF
2, 3
Input capacitance delta, CK and CK#
CDCK
0
0.20
0
0.25
pF
2, 3, 4
Input capacitance, all other inputonly pins
CI
1.0
2.0
1.0
2.0
pF
2, 3, 5
Input capacitance delta, all other inputonly pins
CDI
–0.40
+0.40
–0.50
+0.50
pF
2, 3, 6
Input/output capacitance, DQ, DM, DQS,
DQS#
CIO
1.25
2.5
1.25
2.5
pF
2, 3, 7, 8
CDDQS
0
0.25
0
0.30
pF
2, 3, 8, 9
Input/output capacitance delta, DQ, DM
CDIO
–0.5
+0.5
–0.6
+0.6
pF
2, 3, 8, 10
Input/output capacitance ZQ
CZQ
0
2.5
0
2.5
pF
2, 3, 11
Input/output capacitance delta, DQS,
DQS#
Notes:
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1. TC –40˚C to +105˚C; VDDQ = 1.14–1.3V; VDDCA = 1.14–1.3V; VDD1 = 1.7–1.95V; VDD2 = 1.14–
1.3V.
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Electrical Specifications – IDD Specifications and Conditions
2. This parameter applies to die devices only (does not include package capacitance).
3. This parameter is not subject to production testing. It is verified by design and characterization. The capacitance is measured according to JEP147 (procedure for measuring input capacitance using a vector network analyzer), with VDD1, VDD2, VDDQ, VSS, VSSCA, and
VSSQ applied; all other pins are left floating.
4. Absolute value of CCK - CCK#.
5. CI applies to CS#, CKE, and CA[9:0].
6. CDI = CI - 0.5 × (CCK + CCK#).
7. DM loading matches DQ and DQS.
8. MR3 I/O configuration drive strength OP[3:0] = 0001b (34.3 ohm typical).
9. Absolute value of CDQS and CDQS#.
10. CDIO = CIO - 0.5 × (CDQS + CDQS#) in byte-lane.
11. Maximum external load capacitance on ZQ pin: 5pF.
Electrical Specifications – IDD Specifications and Conditions
The following definitions and conditions are used in the IDD measurement tables unless
stated otherwise:
•
•
•
•
LOW: V IN ≤ V IL(DC)max
HIGH: V IN ≥ V IH(DC)min
STABLE: Inputs are stable at a HIGH or LOW level
SWITCHING: See the following three tables
Table 57: Switching for CA Input Signals
Notes 1–3 apply to all parameters and conditions
CK Rising/ CK Falling/ CK Rising/
CK#Falling CK# Rising CK#Falling
Cycle
CS#
CK Falling/
CK# Rising
CK Rising/
CK#Falling
CK Falling/
CK# Rising
CK Rising/
CK#Falling
CK Falling/
CK# Rising
N
N+1
N+2
N+3
HIGH
HIGH
HIGH
HIGH
CA0
H
L
L
L
L
H
H
H
CA1
H
H
H
L
L
L
L
H
CA2
H
L
L
L
L
H
H
H
CA3
H
H
H
L
L
L
L
H
CA4
H
L
L
L
L
H
H
H
CA5
H
H
H
L
L
L
L
H
CA6
H
L
L
L
L
H
H
H
CA7
H
H
H
L
L
L
L
H
CA8
H
L
L
L
L
H
H
H
CA9
H
H
H
L
L
L
L
H
Notes:
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1. CS# must always be driven HIGH.
2. For each clock cycle, 50% of the CA bus is changing between HIGH and LOW.
3. The noted pattern (N, N + 1, N + 2, N + 3...) is used continuously during IDD measurement for IDD values that require switching on the CA bus.
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Electrical Specifications – IDD Specifications and Conditions
Table 58: Switching for IDD4R
Clock
CKE
CS#
Clock Cycle
Number
Command
CA[2:0]
CA[9:3]
All DQ
Rising
H
L
N
Read_Rising
HLH
LHLHLHL
L
Falling
H
L
N
Read_Falling
LLL
LLLLLLL
L
Rising
H
H
N +1
NOP
LLL
LLLLLLL
H
Falling
H
H
N+1
NOP
HLH
LHLLHLH
L
Rising
H
L
N+2
Read_Rising
HLH
LHLLHLH
H
Falling
H
L
N+2
Read_Falling
LLL
HHHHHHH
H
Rising
H
H
N+3
NOP
LLL
HHHHHHH
H
Falling
H
H
N+3
NOP
HLH
LHLHLHL
L
Notes:
1. Data strobe (DQS) is changing between HIGH and LOW with every clock cycle.
2. The noted pattern (N, N + 1...) is used continuously during IDD measurement for IDD4R.
Table 59: Switching for IDD4W
Clock
CKE
CS#
Clock Cycle
Number
Command
CA[2:0]
CA[9:3]
All DQ
Rising
H
L
N
Write_Rising
LLH
LHLHLHL
L
Falling
H
L
N
Write_Falling
LLL
LLLLLLL
L
Rising
H
H
N +1
NOP
LLL
LLLLLLL
H
Falling
H
H
N+1
NOP
HLH
LHLLHLH
L
Rising
H
L
N+2
Write_Rising
LLH
LHLLHLH
H
Falling
H
L
N+2
Write_Falling
LLL
HHHHHHH
H
Rising
H
H
N+3
NOP
LLL
HHHHHHH
H
Falling
H
H
N+3
NOP
HLH
LHLHLHL
L
Notes:
1. Data strobe (DQS) is changing between HIGH and LOW with every clock cycle.
2. Data masking (DM) must always be driven LOW.
3. The noted pattern (N, N + 1...) is used continuously during IDD measurement for IDD4W.
Table 60: IDD Specification Parameters and Operating Conditions
Notes 1–3 apply to all parameters and conditions
Parameter/Condition
Operating one bank active-precharge current (SDRAM): tCK = tCKmin;
tRC = tRCmin; CKE is HIGH; CS# is HIGH between valid commands; CA bus inputs are switching; Data bus inputs are stable
tCK
tCKmin;
Idle power-down standby current:
=
CKE is LOW; CS# is HIGH;
All banks are idle; CA bus inputs are switching; Data bus inputs are stable
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101
Symbol
Power Supply
IDD01
VDD1
IDD02
VDD2
IDD0in
VDDCA, VDDQ
IDD2P1
VDD1
IDD2P2
VDD2
IDD2P,in
VDDCA, VDDQ
Notes
4
4
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Electrical Specifications – IDD Specifications and Conditions
Table 60: IDD Specification Parameters and Operating Conditions (Continued)
Notes 1–3 apply to all parameters and conditions
Parameter/Condition
Idle power-down standby current with clock stop: CK = LOW, CK# =
HIGH; CKE is LOW; CS# is HIGH; All banks are idle; CA bus inputs are stable;
Data bus inputs are stable
Idle non-power-down standby current: tCK = tCKmin; CKE is HIGH; CS# is
HIGH; All banks are idle; CA bus inputs are switching; Data bus inputs are stable
Idle non-power-down standby current with clock stopped: CK = LOW;
CK# = HIGH; CKE is HIGH; CS# is HIGH; All banks are idle; CA bus inputs are
stable; Data bus inputs are stable
tCK
tCKmin;
Active power-down standby current:
=
CKE is LOW; CS# is
HIGH; One bank is active; CA bus inputs are switching; Data bus inputs are
stable
Active power-down standby current with clock stop: CK = LOW, CK# =
HIGH; CKE is LOW; CS# is HIGH; One bank is active; CA bus inputs are stable;
Data bus inputs are stable
Active non-power-down standby current: tCK = tCKmin; CKE is HIGH; CS#
is HIGH; One bank is active; CA bus inputs are switching; Data bus inputs are
stable
Active non-power-down standby current with clock stopped: CK =
LOW, CK# = HIGH CKE is HIGH; CS# is HIGH; One bank is active; CA bus inputs
are stable; Data bus inputs are stable
tCK
tCKmin;
Operating burst READ current:
=
CS# is HIGH between valid
commands; One bank is active; BL = 4; RL = RL (MIN); CA bus inputs are
switching; 50% data change each burst transfer
tCK
tCKmin;
Operating burst WRITE current:
=
CS# is HIGH between valid
commands; One bank is active; BL = 4; WL = WLmin; CA bus inputs are switching; 50% data change each burst transfer
tCK
tCKmin;
All-bank REFRESH burst current:
=
CKE is HIGH between valid
commands; tRC = tRFCabmin; Burst refresh; CA bus inputs are switching; Data
bus inputs are stable
All-bank REFRESH average current (–30˚C to +85˚C): tCK = tCKmin; CKE is
HIGH between valid commands; tRC = tREFI; CA bus inputs are switching; Data
bus inputs are stable
tCK
tCKmin;
All-bank REFRESH average current (+85˚C to +105˚C):
=
CKE
is HIGH between valid commands; tRC = tREFI; CA bus inputs are switching;
Data bus inputs are stable
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102
Symbol
Power Supply
IDD2PS1
VDD1
IDD2PS2
VDD2
IDD2PS,in
VDDCA, VDDQ
IDD2N1
VDD1
IDD2N2
VDD2
IDD2N,in
VDDCA, VDDQ
IDD2NS1
VDD1
IDD2NS2
VDD2
IDD2NS,in
VDDCA, VDDQ
IDD3P1
VDD1
IDD3P2
VDD2
IDD3P,in
VDDCA, VDDQ
IDD3PS1
VDD1
IDD3PS2
VDD2
IDD3PS,in
VDDCA, VDDQ
IDD3N1
VDD1
IDD3N2
VDD2
IDD3N,in
VDDCA, VDDQ
IDD3NS1
VDD1
IDD3NS2
VDD2
IDD3NS,in
VDDCA, VDDQ
IDD4R1
VDD1
IDD4R2
VDD2
IDD4R,in
VDDCA
IDD4RQ
VDDQ
IDD4W1
VDD1
IDD4W2
VDD2
IDD4W,in
VDDCA, VDDQ
IDD51
VDD1
IDD52
VDD2
IDD5IN
VDDCA, VDDQ
IDD5AB1
VDD1
IDD5AB2
VDD2
IDD5AB,in
VDDCA, VDDQ
IDD5ABET1
VDD1
IDD5ABET2
VDD2
IDD5AB,ETin
VDDCA, VDDQ
Notes
4
4
4
4
4
4
4
5
4
4
4
4, 8
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AC and DC Operating Conditions
Table 60: IDD Specification Parameters and Operating Conditions (Continued)
Notes 1–3 apply to all parameters and conditions
Parameter/Condition
tCK
tCKmin;
Per-bank REFRESH average current (–30˚C to +85˚C):
=
CKE is
HIGH between valid commands; tRC = tREFI/8; CA bus inputs are switching;
Data bus inputs are stable
Per-bank REFRESH average current (+85˚C to +105˚C): tCK = tCKmin; CKE
is HIGH between valid commands; tRC = tREFI/8; CA bus inputs are switching;
Data bus inputs are stable
Self refresh current (–30˚C to +85˚C): CK = LOW, CK# = HIGH; CKE is LOW;
CA bus inputs are stable; Data bus inputs are stable; Maximum 1x self refresh
rate
Self refresh current (+85˚C to +105˚C): CK = LOW, CK# = HIGH; CKE is
LOW; CA bus inputs are stable; Data bus inputs are stable
Deep power-down current: CK = LOW, CK# = HIGH; CKE is LOW; CA bus inputs are stable; Data bus inputs are stable
Notes:
Symbol
Power Supply
Notes
IDD5PB1
VDD1
6
IDD5PB2
VDD2
6
IDD5PB,in
VDDCA, VDDQ
4, 6
IDD5PBET1
VDD1
6
IDD5PBET2
VDD2
6
IDD5PB,ETin
VDDCA, VDDQ
4, 6, 8
IDD61
VDD1
7
IDD62
VDD2
7
IDD6IN
VDDCA, VDDQ
4, 7
IDD6ET1
VDD1
7, 8
IDD6ET2
VDD2
7, 8
IDD6ET,in
VDDCA, VDDQ
4, 7, 8
IDD81
VDD1
8
IDD82
VDD2
8
IDD8IN
VDDCA, VDDQ
4, 8
1. IDD values are the maximum of the distribution of the arithmetic mean.
2. IDD current specifications are tested after the device is properly initialized.
3. The 1x self refresh rate is the rate at which the device is refreshed internally during self
refresh, before going into the extended temperature range.
4. Measured currents are the sum of VDDQ and VDDCA.
5. Guaranteed by design with output reference load and RON = 40 ohm.
6. Per-bank REFRESH is only applicable for LPDDR2-S4 device densities 1Gb or higher.
7. This is the general definition that applies to full-array self refresh.
8. IDD6ET, IDD5ABET, IDD5PBET, and IDD8 are typical values, are sampled only, and are not tested.
AC and DC Operating Conditions
Operation or timing that is not specified is illegal. To ensure proper operation, the device must be initialized properly.
Table 61: Recommended DC Operating Conditions
LPDDR2-S4B
Symbol
Min
Typ
Max
Power Supply
Unit
VDD11
1.70
1.80
1.95
Core power 1
V
VDD2
1.14
1.20
1.30
Core power 2
V
VDDCA
1.14
1.20
1.30
Input buffer power
V
VDDQ
1.14
1.20
1.30
I/O buffer power
V
Note:
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1. VDD1 uses significantly less power than VDD2.
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AC and DC Operating Conditions
Table 62: Input Leakage Current
Parameter/Condition
Symbol
Min
Max
Unit
Notes
Input leakage current: For CA, CKE, CS#, CK, CK#;
Any input 0V ≤ VIN ≤ VDDCA; (All other pins not under
test = 0V)
IL
–2
2
μA
1
VREF supply leakage current: VREFDQ = VDDQ/2, or
VREFCA = VDDCA/2; (All other pins not under test = 0V)
IVREF
–1
1
μA
2
Notes:
1. Although DM is for input only, the DM leakage must match the DQ and DQS/DQS# output leakage specification.
2. The minimum limit requirement is for testing purposes. The leakage current on VREFCA
and VREFDQ pins should be minimal.
Table 63: Operating Temperature Range
Parameter/Condition
WT temperature range
Symbol
1
TCASE
AT temperature range
Notes:
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Min
Max
Unit
–30
+85
˚C
–40
+105
˚C
1. Operating temperature is the case surface temperature at the center of the top side of
the device. For measurement conditions, refer to the JESD51-2 standard.
2. Some applications require operation in the maximum case temperature range, between
85˚C and 105˚C. For some LPDDR2 devices, derating may be necessary to operate in this
range (see the MR4 Device Temperature (MA[7:0] = 04h) table).
3. Either the device operating temperature or the temperature sensor can be used to set
an appropriate refresh rate, determine the need for AC timing derating, and/or monitor
the operating temperature (see Temperature Sensor). When using the temperature sensor, the actual device case temperature may be higher than the TCASE rating that applies
for the operating temperature range. For example, TCASE could be above 85˚C when the
temperature sensor indicates a temperature of less than 85˚C.
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AC and DC Logic Input Measurement Levels for Single-Ended
Signals
AC and DC Logic Input Measurement Levels for Single-Ended Signals
Table 64: Single-Ended AC and DC Input Levels for CA and CS# Inputs
LPDDR2-1066 to LPDDR2-466 LPDDR2-400 to LPDDR2-200
Symbol
Parameter
Min
Max
Min
Max
Unit
Notes
VIHCA(AC)
AC input logic HIGH
VREF + 0.220
Note 2
VREF + 0.300
Note 2
V
1, 2
VILCA(AC)
AC input logic LOW
Note 2
VREF - 0.220
Note 2
VREF - 0.300
V
1, 2
VIHCA(DC)
DC input logic HIGH
VREF + 0.130
VDDCA
VREF + 0.200
VDDCA
V
1
VILCA(DC)
DC input logic LOW
VSSCA
VREF - 0.130
VSSCA
VREF - 0.200
V
1
0.49 × VDDCA
0.51 × VDDCA
0.49 × VDDCA
0.51 × VDDCA
V
3, 4
VREFCA(DC)
Reference voltage for
CA and CS# inputs
Notes:
1. For CA and CS# input-only pins. VREF = VREFCA(DC).
2. See Overshoot and Undershoot Definition.
3. The AC peak noise on VREFCA could prevent VREFCA from deviating more than ±1% VDDCA
from VREFCA(DC) (for reference, approximately ±12mV).
4. For reference, approximately VDDCA/2 ±12mV.
Table 65: Single-Ended AC and DC Input Levels for CKE
Symbol
Min
Max
Unit
Notes
VIHCKE
CKE input HIGH level
Parameter
0.8 × VDDCA
Note 1
V
1
VILCKE
CKE input LOW level
Note 1
0.2 × VDDCA
V
1
Note:
1. See Overshoot and Undershoot Definition.
Table 66: Single-Ended AC and DC Input Levels for DQ and DM
LPDDR2-1066 to LPDDR2-466 LPDDR2-400 to LPDDR2-200
Symbol
VIHDQ(AC)
Parameter
AC input logic HIGH
Min
Max
Min
Max
Unit
Notes
VREF + 0.220
Note 2
VREF + 0.300
Note 2
V
1, 2
VILDQ(AC)
AC input logic LOW
Note 2
VREF - 0.220
Note 2
VREF - 0.300
V
1, 2
VIHDQ(DC)
DC input logic HIGH
VREF + 0.130
VDDQ
VREF + 0.200
VDDQ
V
1
VILDQ(DC)
DC input logic LOW
VSSQ
VREF - 0.130
VSSQ
VREF - 0.200
V
1
0.49 × VDDQ
0.51 × VDDQ
0.49 × VDDQ
0.51 × VDDQ
V
3, 4
VREFDQ(DC)
Reference voltage for
DQ and DM inputs
Notes:
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1. For DQ input-only pins. VREF = VREFDQ(DC).
2. See Overshoot and Undershoot Definition.
3. The AC peak noise on VREFDQ could prevent VREFDQ from deviating more than ±1% VDDQ
from VREFDQ(DC) (for reference, approximately ±12mV).
4. For reference, approximately. VDDQ/2 ±12mV.
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AC and DC Logic Input Measurement Levels for Single-Ended
Signals
VREF Tolerances
The DC tolerance limits and AC noise limits for the reference voltages V REFCA and
VREFDQ are illustrated below. This figure shows a valid reference voltage V REF(t) as a
function of time. V DD is used in place of V DDCA for V REFCA, and V DDQ for V REFDQ. V REF(DC)
is the linear average of V REF(t) over a very long period of time (for example, 1 second)
and is specified as a fraction of the linear average of V DDQ or V DDCA, also over a very long
period of time (for example, 1 second). This average must meet the MIN/MAX requirements in Table 64 (page 105). Additionally, V REF(t) can temporarily deviate from V REF(DC)
by no more than ±1% V DD. V REF(t) cannot track noise on V DDQ or V DDCA if doing so
would force V REF outside these specifications.
Figure 69: VREF DC Tolerance and VREF AC Noise Limits
VDD
Voltage
VREF(AC) noise
VREF(t)
VREF(DC)max
VREF(DC)
VDD/2
VREF(DC)min
VSS
Time
The voltage levels for setup and hold time measurements V IH(AC), V IH(DC), V IL(AC), and
VIL(DC) are dependent on V REF.
VREF DC variations affect the absolute voltage a signal must reach to achieve a valid
HIGH or LOW, as well as the time from which setup and hold times are measured. When
VREF is outside the specified levels, devices will function correctly with appropriate timing deratings as long as:
• VREF is maintained between 0.44 x V DDQ (or V DDCA) and 0.56 x V DDQ (or V DDCA), and
• the controller achieves the required single-ended AC and DC input levels from instantaneous V REF (see Table 64 (page 105)).
System timing and voltage budgets must account for V REF deviations outside this range.
The setup/hold specification and derating values must include time and voltage associated with V REF AC noise. Timing and voltage effects due to AC noise on V REF up to the
specified limit (±1% V DD) are included in LPDDR2 timings and their associated deratings.
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AC and DC Logic Input Measurement Levels for Single-Ended
Signals
Input Signal
Figure 70: LPDDR2-466 to LPDDR2-1066 Input Signal
VIL and VIH levels with ringback
1.550V
Minimum VIL and VIH levels
0.820V
0.730V
VIH(AC)
VIH(DC)
0.624V
0.612V
0.600V
0.588V
0.576V
0.470V
0.380V
VIL(DC)
VIL(AC)
1.200V
VDD
0.820V
VIH(AC)
0.730V
VIH(DC)
0.624V
0.612V
0.600V
0.588V
0.576V
VREF + AC noise
VREF + DC error
VREF - DC error
VREF - AC noise
0.470V
VIL(DC)
0.380V
VIL(AC)
0.000V
VSS
VSS - 0.35V
narrow pulse width
–0.350V
Notes:
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VDD + 0.35V
narrow pulse width
1. Numbers reflect typical values.
2. For CA[9:0], CK, CK#, and CS# VDD stands for VDDCA. For DQ, DM, DQS, and DQS#, VDD
stands for VDDQ.
3. For CA[9:0], CK, CK#, and CS# VSS stands for VSSCA. For DQ, DM, DQS, and DQS#, VSS
stands for VSSQ.
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AC and DC Logic Input Measurement Levels for Single-Ended
Signals
Figure 71: LPDDR2-200 to LPDDR2-400 Input Signal
VIL and VIH levels with ringback
1.550V
Minimum VIL and VIH levels
0.900V
0.800V
VIH(AC)
VIH(DC)
0.624V
0.612V
0.600V
0.588V
0.576V
0.400V
0.300V
VIL(DC)
VIL(AC)
1.200V
VDD
0.900V
VIH(AC)
0.800V
VIH(DC)
0.624V
0.612V
0.600V
0.588V
0.576V
VREF + AC noise
VREF + DC error
VREF - DC error
VREF - AC noise
0.400V
VIL(DC)
0.300V
VIL(AC)
0.000V
VSS
VSS - 0.35V
narrow pulse width
–0.350V
Notes:
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VDD + 0.35V
narrow pulse width
1. Numbers reflect typical values.
2. For CA[9:0], CK, CK#, and CS# VDD stands for VDDCA. For DQ, DM, DQS, and DQS#, VDD
stands for VDDQ.
3. For CA[9:0], CK, CK#, and CS# VSS stands for VSSCA. For DQ, DM, DQS, and DQS#, VSS
stands for VSSQ.
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2Gb: x16, x32, x64 Automotive LPDDR2 SDRAM
AC and DC Logic Input Measurement Levels for Differential
Signals
AC and DC Logic Input Measurement Levels for Differential Signals
Figure 72: Differential AC Swing Time and tDVAC
tDVAC
Differential Voltage
VIH,diff(AC)min
VIH,diff(DC)min
CK, CK#
DQS, DQS#
0.0
VIH,diff(DC)max
tDVAC
1/2 cycle
VIH,diff(AC)max
Time
Table 67: Differential AC and DC Input Levels
For CK and CK#, VREF = VREFCA(DC); For DQS and DQS# VREF = VREFDQ(DC)
LPDDR2-1066 to LPDDR2-466
LPDDR2-400 to LPDDR2-200
Symbol
Parameter
Min
Max
Min
Max
VIH,diff(AC)
Differential input
HIGH AC
2 × (VIH(AC) - VREF)
Note 1
2 × (VIH(AC) - VREF)
Note 1
V
2
VIL,diff(AC)
Differential input
LOW AC
Note 1
2 × (VREF - VIL(AC))
Note 1
2 × (VREF - VIL(AC))
V
2
VIH,diff(DC)
Differential input
HIGH
2 × (VIH(DC) - VREF)
Note 1
2 × (VIH(DC) - VREF)
Note 1
V
3
VIL,diff(DC)
Differential input
LOW
Note 1
2 × (VREF - VIL(DC))
Note 1
2 × (VREF - VIL(DC))
V
3
Notes:
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Unit Notes
1. These values are not defined, however the single-ended signals CK, CK#, DQS, and DQS#
must be within the respective limits (VIH(DC)max, VIL(DC)min) for single-ended signals and
must comply with the specified limitations for overshoot and undershoot (see Overshoot
and Undershoot Definition).
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AC and DC Logic Input Measurement Levels for Differential
Signals
2. For CK and CK#, use VIH/VIL(AC) of CA and VREFCA; for DQS and DQS#, use VIH/VIL(AC) of DQ
and VREFDQ. If a reduced AC HIGH or AC LOW is used for a signal group, the reduced
voltage level also applies.
3. Used to define a differential signal slew rate.
Table 68: CK/CK# and DQS/DQS# Time Requirements Before Ringback
(tDVAC)
tDVAC
(ps) at VIH/VILdiff(AC) =
440mV
tDVAC
(ps) at VIH/VILdiff(AC) =
600mV
Slew Rate (V/ns)
Min
Min
> 4.0
175
75
4.0
170
57
3.0
167
50
2.0
163
38
1.8
162
34
1.6
161
29
1.4
159
22
1.2
155
13
1.0
150
0
< 1.0
150
0
Single-Ended Requirements for Differential Signals
Each individual component of a differential signal (CK, CK#, DQS, and DQS#) must also
comply with certain requirements for single-ended signals.
CK and CK# must meet V SEH(AC)min/VSEL(AC)max in every half cycle. DQS, DQS# must
meet V SEH(AC)min/VSEL(AC)max in every half cycle preceding and following a valid transition.
The applicable AC levels for CA and DQ differ by speed bin.
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AC and DC Logic Input Measurement Levels for Differential
Signals
Figure 73: Single-Ended Requirements for Differential Signals
VDDCA or VDDQ
VSEH(AC)
Differential Voltage
VSEH(AC)min
VDDCA/2 or VDDQ/2
CK or DQS
VSEL(AC)max
VSEL(AC)
VSSCA or VSSQ
Time
Note that while CA and DQ signal requirements are referenced to V REF, the single-ended
components of differential signals also have a requirement with respect to
VDDQ/2 for DQS, and V DDCA/2 for CK.
The transition of single-ended signals through the AC levels is used to measure setup
time. For single-ended components of differential signals, the requirement to reach
VSEL(AC)max or V SEH(AC)min has no bearing on timing. This requirement does, however,
add a restriction on the common mode characteristics of these signals (see "SingleEnded AC and DC Input Levels for CA and CS# Inputs" for CK/CK# single-ended requirements, and "Single-Ended AC and DC Input Levels for DQ and DM" for DQ and
DQM single-ended requirements).
Table 69: Single-Ended Levels for CK, CK#, DQS, DQS#
LPDDR2-1066 to LPDDR2-466
Symbol
VSEH(AC)
VSEL(AC)
Parameter
LPDDR2-400 to LPDDR2-200
Min
Max
Min
Max
Single-ended HIGH
level for strobes
(VDDQ/2) + 0.220
Note 1
(VDDQ/2) + 0.300
Note 1
V
2, 3
Single-ended HIGH
level for CK, CK#
(VDDCA/2) + 0.220
Note 1
(VDDCA/2) + 0.300
Note 1
V
2, 3
Single-ended LOW
level for strobes
Note 1
(VDDQ/2) - 0.220
Note 1
(VDDQ/2) – 0.300
V
2, 3
Single-ended LOW
level for CK, CK#
Note 1
(VDDCA/2) - 0.220
Note 1
(VDDCA/2) – 0.300
V
2, 3
Notes:
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Unit Notes
1. These values are not defined, however, the single-ended signals CK, CK#, DQS0, DQS#0,
DQS1, DQS#1, DQS2, DQS#2, DQS3, DQS#3 must be within the respective limits
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2Gb: x16, x32, x64 Automotive LPDDR2 SDRAM
AC and DC Logic Input Measurement Levels for Differential
Signals
(VIH(DC)max/ VIL(DC)min) for single-ended signals, and must comply with the specified limitations for overshoot and undershoot (See Overshoot and Undershoot Definition).
2. For CK and CK#, use VSEH/VSEL(AC) of CA; for strobes (DQS[3:0] and DQS#[3:0]), use
VIH/VIL(AC) of DQ.
3. VIH(AC) and VIL(AC) for DQ are based on VREFDQ; VSEH(AC) and VSEL(AC) for CA are based on
VREFCA. If a reduced AC HIGH or AC LOW is used for a signal group, the reduced level
applies.
Differential Input Crosspoint Voltage
To ensure tight setup and hold times as well as output skew parameters with respect to
clock and strobe, each crosspoint voltage of differential input signals (CK, CK#, DQS,
and DQS#) must meet the specifications in Table 69 (page 111). The differential input
crosspoint voltage (VIX) is measured from the actual crosspoint of the true signal and its
and complement to the midlevel between V DD and V SS.
Figure 74: VIX Definition
VDDCA, VDDQ
VDDCA, VDDQ
CK#, DQS#
CK#, DQS#
X
VIX
VIX
VDDCA/2,
VDDQ/2
VDDCA/2,
VDDQ/2
X
X
VIX
X
VIX
CK, DQS
CK, DQS
VSSCA, VSSQ
VSSCA, VSSQ
Table 70: Crosspoint Voltage for Differential Input Signals (CK, CK#, DQS, DQS#)
LPDDR2-1066 to LPDDR2-200
Symbol
Parameter
Min
Max
Unit
Notes
VIXCA(AC)
Differential input crosspoint voltage relative to VDDCA/2 for CK and CK#
–120
120
mV
1, 2
VIXDQ(AC)
Differential input crosspoint voltage relative to VDDQ/2 for DQS and DQ#
–120
120
mV
1, 2
Notes:
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1. The typical value of VIX(AC) is expected to be about 0.5 × VDD of the transmitting device,
and it is expected to track variations in VDD. VIX(AC) indicates the voltage at which differential input signals must cross.
2. For CK and CK#, VREF = VREFCA(DC). For DQS and DQS#, VREF = VREFDQ(DC).
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Output Characteristics and Operating Conditions
Input Slew Rate
Table 71: Differential Input Slew Rate Definition
Measured1
Description
From
To
Defined by
Differential input slew rate for rising
edge (CK/CK# and DQS/DQS#)
VIL,diff,max
VIH,diff,min
[VIH,diff,min - VIL,diff,max] / ΔTRdiff
Differential input slew rate for falling
edge (CK/CK# and DQS/DQS#)
VIH,diff,min
VIL,diff,max
[VIH,diff,min - VIL,diff,max] / ΔTFdiff
Note:
1. The differential signals (CK/CK# and DQS/DQS#) must be linear between these thresholds.
Figure 75: Differential Input Slew Rate Definition for CK, CK#, DQS, and DQS#
ΔTRdiff
Differential Input Voltage
ΔTFdiff
VIH,diff,min
0
VIL,diff,max
Time
Output Characteristics and Operating Conditions
Table 72: Single-Ended AC and DC Output Levels
Symbol
Parameter
Value
Unit
Notes
VOH(AC)
AC output HIGH measurement level (for output slew rate)
VREF + 0.12
V
VOL(AC)
AC output LOW measurement level (for output slew rate)
VREF - 0.12
V
VOH(DC)
DC output HIGH measurement level (for I-V curve linearity)
0.9 x VDDQ
V
1
VOL(DC)
DC output LOW measurement level (for I-V curve linearity)
2
IOZ
MMpupd
Output leakage current (DQ, DM, DQS, DQS#); DQ,
DQS, DQS# are disabled; 0V ≤ VOUT ≤ VDDQ
Delta output impedance between pull-up and pulldown for DQ/DM
Notes:
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0.1 x VDDQ
V
MIN
–5
μA
MAX
+5
μA
MIN
–15
%
MAX
+15
%
1. IOH = –0.1mA.
2. IOL = 0.1mA.
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Output Characteristics and Operating Conditions
Table 73: Differential AC and DC Output Levels
Value
Unit
VOHdiff(AC)
Symbol
AC differential output HIGH measurement level (for output SR)
Parameter
+ 0.2 x VDDQ
V
VOLdiff(AC)
AC differential output LOW measurement level (for output SR)
- 0.2 x VDDQ
V
Single-Ended Output Slew Rate
With the reference load for timing measurements, the output slew rate for falling and
rising edges is defined and measured between V OL(AC) and V OH(AC) for single-ended
signals.
Table 74: Single-Ended Output Slew Rate Definition
Measured
Description
From
To
Defined by
Single-ended output slew rate for rising edge
VOL(AC)
VOH(AC)
[VOH(AC) - VOL(AC)] / ΔTRSE
Single-ended output slew rate for falling edge
VOH(AC)
VOL(AC)
[VOH(AC) - VOL(AC)] / ΔTFSE
Note:
1. Output slew rate is verified by design and characterization and may not be subject to
production testing.
Figure 76: Single-Ended Output Slew Rate Definition
ΔTRSE
Single-Ended Output Voltage (DQ)
ΔTFSE
VOH(AC)
VREF
VOL(AC)
Time
Table 75: Single-Ended Output Slew Rate
Notes 1–5 apply to all parameters conditions
Value
Parameter
Symbol
Min
Max
Unit
Single-ended output slew rate (output impedance = 40Ω ±30%)
SRQSE
1.5
3.5
V/ns
Single-ended output slew rate (output impedance = 60Ω ±30%)
SRQSE
1.0
2.5
V/ns
0.7
1.4
–
Output slew-rate-matching ratio (pull-up to pull-down)
Notes:
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1. Definitions: SR = slew rate; Q = output (similar to DQ = data-in, data-out); SE = singleended signals.
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Output Characteristics and Operating Conditions
2. Measured with output reference load.
3. The ratio of pull-up to pull-down slew rate is specified for the same temperature and
voltage over the entire temperature and voltage range. For a given output, the ratio
represents the maximum difference between pull-up and pull-down drivers due to process variation.
4. The output slew rate for falling and rising edges is defined and measured between
VOL(AC) and VOH(AC).
5. Slew rates are measured under typical simultaneous switching output (SSO) conditions,
with one-half of DQ signals per data byte driving HIGH and one-half of DQ signals per
data byte driving LOW.
Differential Output Slew Rate
With the reference load for timing measurements, the output slew rate for falling and
rising edges is defined and measured between V OL,diff(AC) and V OH,diff(AC) for differential
signals.
Table 76: Differential Output Slew Rate Definition
Measured
Description
From
To
Defined by
Differential output slew rate for rising edge
VOL,diff(AC)
VOH,diff(AC)
[VOH,diff(AC) - VOL,diff(AC)] / ΔTRdiff
Differential output slew rate for falling edge
VOH,diff(AC)
VOL,diff(AC)
[VOH,diff(AC) - VOL,diff(AC)] / ΔTFdiff
Note:
1. Output slew rate is verified by design and characterization and may not be subject to
production testing.
Differential Output Voltage (DQS, DQS#)
Figure 77: Differential Output Slew Rate Definition
ΔTFdiff
ΔTRdiff
VOH,diff(AC)
0
VOL,diff(AC)
Time
Table 77: Differential Output Slew Rate
Value
Parameter
Differential output slew rate (output impedance = 40Ω ±30%)
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115
Symbol
Min
Max
Unit
SRQdiff
3.0
7.0
V/ns
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2Gb: x16, x32, x64 Automotive LPDDR2 SDRAM
Output Characteristics and Operating Conditions
Table 77: Differential Output Slew Rate (Continued)
Value
Parameter
Differential output slew rate (output impedance = 60Ω ±30%)
Notes:
Symbol
Min
Max
Unit
SRQdiff
2.0
5.0
V/ns
1. Definitions: SR = slew rate; Q = output (similar to DQ = data-in, data-out); SE = singleended signals.
2. Measured with output reference load.
3. The output slew rate for falling and rising edges is defined and measured between
VOL(AC) and VOH(AC).
4. Slew rates are measured under typical simultaneous switching output (SSO) conditions,
with one-half of DQ signals per data byte driving HIGH and one-half of DQ signals per
data byte driving LOW.
Table 78: AC Overshoot/Undershoot Specification
Applies for CA[9:0], CS#, CKE, CK, CK#, DQ, DQS, DQS#, DM
Parameter
1066
933
800
667
533
400
333
Unit
Maximum peak amplitude provided for overshoot area
0.35
0.35
0.35
0.35
0.35
0.35
0.35
V
Maximum peak amplitude provided for undershoot area
0.35
0.35
0.35
0.35
0.35
0.35
0.35
V
Maximum area above VDD1
0.15
0.17
0.20
0.24
0.30
0.40
0.48
V/ns
Maximum area below VSS2
0.15
0.17
0.20
0.24
0.30
0.40
0.48
V/ns
Notes:
1. VDD stands for VDDCA for CA[9:0], CK, CK#, CS#, and CKE. VDD stands for VDDQ for DQ,
DM, DQS, and DQS#.
2. VSS stands for VSSCA for CA[9:0], CK, CK#, CS#, and CKE. VSS stands for VSSQ for DQ, DM,
DQS, and DQS#.
Figure 78: Overshoot and Undershoot Definition
Volts (V)
Maximum amplitude
VDD
Time (ns)
VSS
Maximum amplitude
Notes:
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Overshoot area
Undershoot area
1. VDD stands for VDDCA for CA[9:0], CK, CK#, CS#, and CKE. VDD stands for VDDQ for DQ,
DM, DQS, and DQS#.
2. VSS stands for VSSCA for CA[9:0], CK, CK#, CS#, and CKE. VSS stands for VSSQ for DQ, DM,
DQS, and DQS#.
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Output Driver Impedance
HSUL_12 Driver Output Timing Reference Load
The timing reference loads are not intended as a precise representation of any particular system environment or a depiction of the actual load presented by a production tester. System designers should use IBIS or other simulation tools to correlate the timing
reference load to a system environment. Manufacturers correlate to their production
test conditions, generally with one or more coaxial transmission lines terminated at the
tester electronics.
Figure 79: HSUL_12 Driver Output Reference Load for Timing and Slew Rate
LPDDR2
VREF
0.5 × VDDQ
50Ω
Output
VTT = 0.5 × VDDQ
C LOAD = 5pF
Note:
1. All output timing parameter values (tDQSCK, tDQSQ, tQHS, tHZ, tRPRE etc.) are reported
with respect to this reference load. This reference load is also used to report slew rate.
Output Driver Impedance
Output driver impedance is selected by a mode register during initialization. To achieve
tighter tolerances, ZQ calibration is required. Output specifications refer to the default
output drive unless specifically stated otherwise. The output driver impedance R ON is
defined by the value of the external reference resistor RZQ as follows:
RONPU = VDDQ - VOUT
ABS(IOUT)
When RONPD is turned off.
RONPD =
VOUT
ABS(IOUT)
When RONPU is turned off.
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Output Driver Impedance
Figure 80: Output Driver
Chip in Drive Mode
Output Driver
VDDQ
IPU
To other
circuitry
(RCV, etc.)
RONPU
IOUT
RONPD
DQ
VOUT
IPD
VSSQ
Output Driver Impedance Characteristics with ZQ Calibration
Output driver impedance is defined by the value of the external reference resistor RZQ.
Typical RZQ is 240 ohms.
Table 79: Output Driver DC Electrical Characteristics with ZQ Calibration
Notes 1–4 apply to all parameters and conditions
RONnom
Resistor
34.3Ω
40.0Ω
48.0Ω
60.0Ω
80.0Ω
120.0Ω
Mismatch between
pull-up and pull-down
Notes:
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VOUT
Min
Typ
Max
Unit
RON34PD
0.5 × VDDQ
0.85
1.00
1.15
RZQ/7
RON34PU
0.5 × VDDQ
0.85
1.00
1.15
RZQ/7
RON40PD
0.5 × VDDQ
0.85
1.00
1.15
RZQ/6
RON40PU
0.5 × VDDQ
0.85
1.00
1.15
RZQ/6
RON48PD
0.5 × VDDQ
0.85
1.00
1.15
RZQ/5
RON48PU
0.5 × VDDQ
0.85
1.00
1.15
RZQ/5
RON60PD
0.5 × VDDQ
0.85
1.00
1.15
RZQ/4
RON60PU
0.5 × VDDQ
0.85
1.00
1.15
RZQ/4
RON80PD
0.5 × VDDQ
0.85
1.00
1.15
RZQ/3
RON80PU
0.5 × VDDQ
0.85
1.00
1.15
RZQ/3
RON120PD
0.5 × VDDQ
0.85
1.00
1.15
RZQ/2
RON120PU
0.5 × VDDQ
0.85
1.00
1.15
RZQ/2
+15.00
%
MMPUPD
–15.00
Notes
5
1. Applies across entire operating temperature range after calibration.
2. RZQ = 240Ω.
3. The tolerance limits are specified after calibration, with fixed voltage and temperature.
For behavior of the tolerance limits if temperature or voltage changes after calibration,
see Output Driver Temperature and Voltage Sensitivity.
4. Pull-down and pull-up output driver impedances should be calibrated at 0.5 x VDDQ.
5. Measurement definition for mismatch between pull-up and pull-down, MMPUPD:
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Output Driver Impedance
Measure RONPU and RONPD, both at 0.5 × VDDQ:
MMPUPD =
RONPU – RONPD
× 100
RON,nom
For example, with MMPUPD (MAX) = 15% and RONPD = 0.85, RONPU must be less than 1.0.
Output Driver Temperature and Voltage Sensitivity
If temperature and/or voltage change after calibration, the tolerance limits widen.
Table 80: Output Driver Sensitivity Definition
Resistor
VOUT
Min
Max
Unit
RONPD
0.5 × VDDQ
85 – (dRONdT × |ΔT|) – (dRONdV × |ΔV|)
115 + (dRONdT × |ΔT|) – (dRONdV × |ΔV|)
%
RONPU
Notes:
1. ΔT = T - T (at calibration). ΔV = V - V (at calibration).
2. dRONdT and dRONdV are not subject to production testing; they are verified by design
and characterization.
Table 81: Output Driver Temperature and Voltage Sensitivity
Symbol
Parameter
Min
Max
Unit
RONdT
RON temperature sensitivity
0.00
0.75
%/˚C
RONdV
RON voltage sensitivity
0.00
0.20
%/mV
Output Impedance Characteristics Without ZQ Calibration
Output driver impedance is defined by design and characterization as the default setting.
Table 82: Output Driver DC Electrical Characteristics Without ZQ Calibration
RONnom
Resistor
VOUT
Min
Typ
Max
Unit
34.3Ω
RON34PD
0.5 × VDDQ
0.70
1.00
1.30
RZQ/7
RON34PU
0.5 × VDDQ
0.70
1.00
1.30
RZQ/7
RON40PD
0.5 × VDDQ
0.70
1.00
1.30
RZQ/6
RON40PU
0.5 × VDDQ
0.70
1.00
1.30
RZQ/6
RON48PD
0.5 × VDDQ
0.70
1.00
1.30
RZQ/5
RON48PU
0.5 × VDDQ
0.70
1.00
1.30
RZQ/5
RON60PD
0.5 × VDDQ
0.70
1.00
1.30
RZQ/4
RON60PU
0.5 × VDDQ
0.70
1.00
1.30
RZQ/4
RON80PD
0.5 × VDDQ
0.70
1.00
1.30
RZQ/3
RON80PU
0.5 × VDDQ
0.70
1.00
1.30
RZQ/3
RON120PD
0.5 × VDDQ
0.70
1.00
1.30
RZQ/2
RON120PU
0.5 × VDDQ
0.70
1.00
1.30
RZQ/2
40.0Ω
48.0Ω
60.0Ω
80.0Ω
120.0Ω
Notes:
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1. Applies across entire operating temperature range without calibration.
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Output Driver Impedance
2. RZQ = 240Ω.
Table 83: I-V Curves
RON = 240Ω (RZQ)
Pull-Down
Pull-Up
Current (mA) / RON (ohms)
Current (mA) / RON (ohms)
Default Value after
ZQRESET
With Calibration
Default Value after
ZQRESET
Voltage (V)
Min (mA)
Max (mA)
Min (mA)
Max (mA)
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.05
0.19
0.32
0.21
0.26
–0.19
–0.32
–0.21
–0.26
0.10
0.38
0.64
0.40
0.53
–0.38
–0.64
–0.40
–0.53
0.15
0.56
0.94
0.60
0.78
–0.56
–0.94
–0.60
–0.78
0.20
0.74
1.26
0.79
1.04
–0.74
–1.26
–0.79
–1.04
0.25
0.92
1.57
0.98
1.29
–0.92
–1.57
–0.98
–1.29
0.30
1.08
1.86
1.17
1.53
–1.08
–1.86
–1.17
–1.53
0.35
1.25
2.17
1.35
1.79
–1.25
–2.17
–1.35
–1.79
0.40
1.40
2.46
1.52
2.03
–1.40
–2.46
–1.52
–2.03
0.45
1.54
2.74
1.69
2.26
–1.54
–2.74
–1.69
–2.26
0.50
1.68
3.02
1.86
2.49
–1.68
–3.02
–1.86
–2.49
0.55
1.81
3.30
2.02
2.72
–1.81
–3.30
–2.02
–2.72
0.60
1.92
3.57
2.17
2.94
–1.92
–3.57
–2.17
–2.94
0.65
2.02
3.83
2.32
3.15
–2.02
–3.83
–2.32
–3.15
0.70
2.11
4.08
2.46
3.36
–2.11
–4.08
–2.46
–3.36
0.75
2.19
4.31
2.58
3.55
–2.19
–4.31
–2.58
–3.55
0.80
2.25
4.54
2.70
3.74
–2.25
–4.54
–2.70
–3.74
0.85
2.30
4.74
2.81
3.91
–2.30
–4.74
–2.81
–3.91
0.90
2.34
4.92
2.89
4.05
–2.34
–4.92
–2.89
–4.05
0.95
2.37
5.08
2.97
4.23
–2.37
–5.08
–2.97
–4.23
1.00
2.41
5.20
3.04
4.33
–2.41
–5.20
–3.04
–4.33
1.05
2.43
5.31
3.09
4.44
–2.43
–5.31
–3.09
–4.44
1.10
2.46
5.41
3.14
4.52
–2.46
–5.41
–3.14
–4.52
1.15
2.48
5.48
3.19
4.59
–2.48
–5.48
–3.19
–4.59
1.20
2.50
5.55
3.23
4.65
–2.50
–5.55
–3.23
–4.65
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120
Min (mA)
Max (mA)
With Calibration
Min (mA)
Max (mA)
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Output Driver Impedance
Figure 81: Output Impedance = 240 Ohms, I-V Curves After ZQRESET
6
PD (MAX)
PD (MIN)
PU MAX)
4
PU (MIN)
mA
2
0
–2
–4
–6
0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1.0
1.1
1.2
Voltage
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Output Driver Impedance
Figure 82: Output Impedance = 240 Ohms, I-V Curves After Calibration
6
PD (MAX)
PD (MIN)
PU MAX)
4
PU (MIN)
mA
2
0
–2
–4
–6
0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1.0
1.1
1.2
Voltage
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Clock Specification
Clock Specification
The specified clock jitter is a random jitter with Gaussian distribution. Input clocks violating minimum or maximum values may result in device malfunction.
Table 84: Definitions and Calculations
Symbol
tCK(avg)
Description
and
nCK
Calculation
The average clock period across any consecutive
200-cycle window. Each clock period is calculated tCK(avg) =
from rising clock edge to rising clock edge.
Unit tCK(avg) represents the actual clock average
tCK(avg)of the input clock under operation. Unit
nCK represents one clock cycle of the input clock,
counting from actual clock edge to actual clock
edge.
Notes
N
Σ tCK
j
j=1
/N
Where N = 200
tCK(avg)can change no more than ±1% within a
100-clock-cycle window, provided that all jitter
and timing specifications are met.
tCK(abs)
The absolute clock period, as measured from one
rising clock edge to the next consecutive rising
clock edge.
tCH(avg)
The average HIGH pulse width, as calculated
across any 200 consecutive HIGH pulses.
1
N
tCH(avg) =
Σ tCH
/(N × tCK(avg))
j
j=1
Where N = 200
tCL(avg)
The average LOW pulse width, as calculated
across any 200 consecutive LOW pulses.
N
tCL(avg) =
Σ tCL
j=1
j
/(N × tCK(avg))
Where N = 200
tJIT(per)
The single-period jitter defined as the largest detJIT(per) = min/max of tCK – tCK(avg)
i
viation of any signal tCK from tCK(avg).
1
Where i = 1 to 200
tJIT(per),act
The actual clock jitter for a given system.
tJIT(per),
The specified clock period jitter allowance.
allowed
tJIT(cc)
The absolute difference in clock periods between
tJIT(cc) = max of tCK
t
i + 1 – CKi
two consecutive clock cycles. tJIT(cc) defines the
cycle-to-cycle jitter.
1
tERR(nper)
The cumulative error across n multiple consecutive cycles from tCK(avg).
1
i+n–1
tERR(nper) =
Σ
tCK – (n × tCK(avg))
j
j=i
tERR(nper),act
The actual cumulative error over n cycles for a
given system.
tERR(nper),
allowed
The specified cumulative error allowance over n
cycles.
tERR(nper),min
The minimum tERR(nper).
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tERR(nper),min = (1 + 0.68LN(n)) × tJIT(per),min
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Clock Period Jitter
Table 84: Definitions and Calculations (Continued)
Symbol
Description
Calculation
tERR(nper),max
The maximum tERR(nper).
tERR(nper),max = (1 + 0.68LN(n)) × tJIT(per),max
tJIT(duty)
Defined with absolute and average specifications tJIT(duty),min =
for tCH and tCL, respectively.
MIN((tCH(abs),min – tCH(avg),min),
Notes
2
(tCL(abs),min – tCL(avg),min)) × tCK(avg)
tJIT(duty),max
=
MAX((tCH(abs),max – tCH(avg),max),
(tCL(abs),max – tCL(avg),max)) × tCK(avg)
Notes:
tCK(abs), tCH(abs),
1. Not subject to production testing.
2. Using these equations, tERR(nper) tables can be generated for each tJIT(per),act value.
and tCL(abs)
These parameters are specified with their average values; however, the relationship between the average timing and the absolute instantaneous timing (defined in the following table) is applicable at all times.
Table 85: tCK(abs), tCH(abs), and tCL(abs) Definitions
Parameter
Symbol
Absolute clock period
tCK(abs)
tCK(avg),min
+
Absolute clock HIGH pulse width
tCH(abs)
tCH(avg),min
+ tJIT(duty),min2/tCK(avg)min
tCK(avg)
Absolute clock LOW pulse width
tCL(abs)
tCL(avg),min
+ tJIT(duty),min2/tCK(avg)min
tCK(avg)
Notes:
Minimum
tJIT(per),min
Unit
ps1
1. tCK(avg),min is expressed in ps for this table.
2. tJIT(duty),min is a negative value.
Clock Period Jitter
LPDDR2 devices can tolerate some clock period jitter without core timing parameter
derating. This section describes device timing requirements with clock period jitter
(tJIT(per)) in excess of the values found in the AC Timing section. Calculating cycle time
derating and clock cycle derating are also described.
Clock Period Jitter Effects on Core Timing Parameters
Core timing parameters (tRCD, tRP, tRTP, tWR, tWRA, tWTR, tRC, tRAS, tRRD, tFAW) extend across multiple clock cycles. Clock period jitter impacts these parameters when
measured in numbers of clock cycles. Within the specification limits, the device is characterized and verified to support tnPARAM = RU[tPARAM/tCK(avg)]. During device operation where clock jitter is outside specification limits, the number of clocks or
tCK(avg), may need to be increased based on the values for each core timing parameter.
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Clock Period Jitter
Cycle Time Derating for Core Timing Parameters
For a given number of clocks (tnPARAM), when tCK(avg) and tERR(tnPARAM),act exceed
cycle time derating may be required for core timing parameters.
tERR(tnPARAM),allowed,
t
t
t
t
t
CycleTimeDerating = max PARAM + ERR( nPARAM),act – ERR( nPARAM),allowed – tCK(avg) , 0
tnPARAM
Cycle time derating analysis should be conducted for each core timing parameter. The
amount of cycle time derating required is the maximum of the cycle time deratings determined for each individual core timing parameter.
Clock Cycle Derating for Core Timing Parameters
For each core timing parameter and a given number of clocks (tnPARAM), clock cycle
derating should be specified with tJIT(per).
For a given number of clocks (tnPARAM), when tCK(avg) plus (tERR(tnPARAM),act) exceed the supported cumulative tERR(tnPARAM),allowed, derating is required. If the
equation below results in a positive value for a core timing parameter (tCORE), the required clock cycle derating will be that positive value (in clocks).
t
t
t
t
t
ClockCycleDerating = RU PARAM + ERR( nPARAM),act – ERR( nPARAM),allowed – tnPARAM
tCK(avg)
Cycle-time derating analysis should be conducted for each core timing parameter.
Clock Jitter Effects on Command/Address Timing Parameters
Command/address timing parameters (tIS, tIH, tISCKE, tIHCKE, tISb, tIHb, tISCKEb,
tIHCKEb) are measured from a command/address signal (CKE, CS, or CA[9:0]) transition edge to its respective clock signal (CK/CK#) crossing. The specification values are
not affected by the tJIT(per) applied, because the setup and hold times are relative to
the clock signal crossing that latches the command/address. Regardless of clock jitter
values, these values must be met.
Clock Jitter Effects on READ Timing Parameters
tRPRE
When the device is operated with input clock jitter, tRPRE must be derated by the
tJIT(per),act,max of the input clock that exceeds tJIT(per),allowed,max. Output deratings are relative to the input clock:
tRPRE(min,derated) = 0.9 – tJIT(per),act,max – tJIT(per),allowed,max
tCK(avg)
For example, if the measured jitter into a LPDDR2-800 device has tCK(avg) = 2500ps,
= –172ps, and tJIT(per),act,max = +193ps, then tRPRE,min,derated =
t
0.9 - ( JIT(per),act,max - tJIT(per),allowed,max)/tCK(avg) = 0.9 - (193 - 100)/2500 =
0.8628 tCK(avg).
tJIT(per),act,min
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Clock Period Jitter
tLZ(DQ), tHZ(DQ), tDQSCK, tLZ(DQS), tHZ(DQS)
These parameters are measured from a specific clock edge to a data signal transition
(DMn or DQm, where: n = 0, 1, 2, or 3; and m = DQ[31:0]), and specified timings must be
met with respect to that clock edge. Therefore, they are not affected by tJIT(per).
tQSH, tQSL
These parameters are affected by duty cycle jitter, represented by tCH(abs)min and
parameters determine the absolute data valid window at the device
pin. The absolute minimum data valid window at the device pin = min [( tQSH(abs)min
× tCK(avg)min - tDQSQmax - tQHSmax), (tQSL(abs)min × tCK(avg)min - tDQSQmax tQHSmax)]. This minimum data valid window must be met at the target frequency regardless of clock jitter.
tCL(abs)min. These
tRPST
tRPST
is affected by duty cycle jitter, represented by tCL(abs). Therefore, tRPST(abs)min
can be specified by tCL(abs)min. tRPST(abs)min = tCL(abs)min - 0.05 = tQSL(abs)min.
Clock Jitter Effects on WRITE Timing Parameters
tDS, tDH
These parameters are measured from a data signal (DMn or DQm, where n = 0, 1, 2, 3;
and m = DQ[31:0]) transition edge to its respective data strobe signal (DQSn, DQSn#: n
= 0,1,2,3) crossing. The specification values are not affected by the amount of tJIT(per)
applied, because the setup and hold times are relative to the clock signal crossing that
latches the command/address. Regardless of clock jitter values, these values must be
met.
tDSS, tDSH
These parameters are measured from a data strobe signal crossing (DQSx, DQSx#) to its
clock signal crossing (CK/CK#). The specification values are not affected by the amount
of tJIT(per)) applied, because the setup and hold times are relative to the clock signal
crossing that latches the command/address. Regardless of clock jitter values, these values must be met.
tDQSS
tDQSS
is measured from the clock signal crossing (CK/CK#) to the first latching data
strobe signal crossing (DQSx, DQSx#). When the device is operated with input clock jitter, this parameter must be derated by the actual tJIT(per),act of the input clock in excess of tJIT(per),allowed.
tDQSS(min,derated) = 0.75 - tJIT(per),act,min – tJIT(per),allowed, min
tCK(avg)
tDQSS(max,derated) = 1.25 – tJIT(per),act,max – tJIT(per),allowed, max
tCK(avg)
For example, if the measured jitter into an LPDDR2-800 device has tCK(avg) = 2500ps,
= -172ps, and tJIT(per),act,max = +193ps, then:
tJIT(per),act,min
tDQSS,(min,derated)
= 0.75 - (tJIT(per),act,min - tJIT(per),allowed,min)/tCK(avg) =
0.75 - (-172 + 100)/2500 = 0.7788 tCK(avg), and
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126
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Refresh Requirements
tDQSS,(max,derated)
= 1.25 - (tJIT(per),act,max - tJIT(per),allowed,max)/tCK(avg) =
1.25 - (193 - 100)/2500 = 1.2128 tCK(avg).
Refresh Requirements
Table 86: Refresh Requirement Parameters (Per Density)
Parameter
Symbol
Number of banks
64Mb
128Mb 256Mb 512Mb
1Gb
2Gb
4Gb
8Gb
Unit
4
4
4
4
8
8
8
8
Refresh window: TCASE ≤ 85˚
tREFW
32
32
32
32
32
32
32
32
ms
Refresh window:
85˚C < TCASE ≤ 105˚C
tREFW
8
8
8
8
8
8
8
8
ms
Required number of REFRESH
commands (MIN)
R
2048
2048
4096
4096
4096
8192
8192
8192
Average time beREFab
tween REFRESH com- REFpb
mands (for reference
only) TCASE ≤ 85˚C
tREFI
15.6
15.6
7.8
7.8
7.8
3.9
3.9
3.9
μs
0.975
0.4875
0.4875
0.4875
μs
130
130
130
210
ns
60
60
60
90
ns
4.16
4.16
4.16
6.72
μs
tREFIpb
Refresh cycle time
tRFCab
Per-bank REFRESH cycle time
tRFCpb
Burst REFRESH window =
4 × 8 × tRFCab
tREFBW
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(REFpb not supported below 1Gb)
90
90
90
90
na
2.88
2.88
2.88
127
2.88
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AC Timing
AC Timing
Table 87: AC Timing
Notes 1–2 apply to all parameters and conditions. AC timing parameters must satisfy the tCK minimum conditions (in multiples of tCK) as well as the timing specifications when values for both are indicated.
Parameter
Symbol
Maximum frequency
Min/ tCK
Max Min 1066
Data Rate
933
800
667
533
400
333
Unit Notes
–
–
533
466
400
333
266
200
166
MHz
MIN
–
1.875
2.15
2.5
3
3.75
5
6
ns
MAX
–
100
100
100
100
100
100
100
MIN
–
0.45
0.45
0.45
0.45
0.45
0.45
0.45
MAX
–
0.55
0.55
0.55
0.55
0.55
0.55
0.55 (avg)
MIN
–
0.45
0.45
0.45
0.45
0.45
0.45
0.45
MAX
–
0.55
0.55
0.55
0.55
0.55
0.55
Clock Timing
Average clock period
tCK(avg)
Average HIGH pulse width
tCH(avg)
Average LOW pulse width
tCL(avg)
Absolute clock period
tCK(abs)
Absolute clock HIGH pulse width
tCH(abs)
Absolute clock LOW pulse width
Clock period jitter
(with supported jitter)
Maximum clock jitter between
two consectuive clock cycles
(with supported jitter)
Duty cycle jitter
(with supported jitter)
MIN
tCK(avg)min
–
±
tCK
tCK
(avg)
0.55
tJIT(per)min
ps
tCK
MIN
–
0.43
0.43
0.43
0.43
0.43
0.43
0.43
MAX
–
0.57
0.57
0.57
0.57
0.57
0.57
0.57 (avg)
MIN
–
0.43
0.43
0.43
0.43
0.43
0.43
0.43
MAX
–
0.57
0.57
0.57
0.57
0.57
0.57
0.57 (avg)
tJIT(per),
MIN
–
-90
-95
-100 -110 -120 -140 -150
allowed
MAX
–
90
95
100
110
120
140
150
tJIT(cc),
MAX
–
180
190
200
220
240
280
300
MIN
–
tCL(abs)
tCK
ps
ps
allowed
tJIT(duty),
MIN ((tCH(abs),min - tCH(avg),min),
- tCL(avg),min)) × tCK(avg)
ps
(tCL(abs),min
allowed
MAX
–
MAX ((tCH(abs),max - tCH(avg),max),
- tCL(avg),max)) × tCK(avg)
(tCL(abs),max
Cumulative errors across 2 cycles
Cumulative errors across 3 cycles
Cumulative errors across 4 cycles
Cumulative errors across 5 cycles
Cumulative errors across 6 cycles
Cumulative errors across 7 cycles
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tERR(2per),
MIN
–
-132
-140 -147 -162 -177 -206 -221
allowed
MAX
–
132
140
tERR(3per),
MIN
–
-157
-166 -175 -192 -210 -245 -262
allowed
MAX
–
157
166
tERR(4per),
MIN
–
-175
-185 -194 -214 -233 -272 -291
allowed
MAX
–
175
185
tERR(5per),
MIN
–
-188
-199 -209 -230 -251 -293 -314
allowed
MAX
–
188
199
tERR(6per),
MIN
–
-200
-211 -222 -244 -266 -311 -333
allowed
MAX
–
200
211
tERR(7per),
MIN
–
-209
-221 -232 -256 -279 -325 -348
allowed
MAX
–
209
221
128
147
175
194
209
222
232
162
192
214
230
244
256
177
210
233
251
266
279
206
245
272
293
311
325
ps
221
ps
262
ps
291
ps
314
ps
333
ps
348
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2Gb: x16, x32, x64 Automotive LPDDR2 SDRAM
AC Timing
Table 87: AC Timing (Continued)
Notes 1–2 apply to all parameters and conditions. AC timing parameters must satisfy the tCK minimum conditions (in multiples of tCK) as well as the timing specifications when values for both are indicated.
Parameter
Cumulative errors across 8 cycles
Cumulative errors across 9 cycles
Cumulative errors across 10 cycles
Cumulative errors across 11 cycles
Cumulative errors across 12 cycles
Cumulative errors across n = 13,
14, 15…, 49, 50 cycles
Data Rate
Min/ tCK
Max Min 1066
933
tERR(8per),
MIN
–
-217
-229 -241 -266 -290 -338 -362
allowed
MAX
–
217
229
tERR(9per),
MIN
–
-224
-237 -249 -274 -299 -349 -374
allowed
MAX
–
224
237
tERR(10per),
MIN
–
-231
-244 -257 -282 -308 -359 -385
allowed
MAX
–
231
244
tERR(11per),
MIN
–
-237
-250 -263 -289 -316 -368 -395
allowed
MAX
–
237
250
tERR(12per),
MIN
–
-242
-256 -269 -296 -323 -377 -403
allowed
MAX
–
242
256
Symbol
tERR(nper),
800
241
249
257
263
269
667
266
274
282
289
296
tERR(nper),allowed,min
MIN
533
290
299
308
316
323
400
338
349
359
368
377
333
Unit Notes
ps
362
ps
374
ps
385
ps
395
ps
403
= (1 + 0.68ln(n)) ×
ps
tJIT(per),allowed,min
allowed
tERR(nper),
MAX
allowed,max = (1 + 0.68ln(n)) ×
tJIT(per),allowed,max
ZQ Calibration Parameters
tZQINIT
MIN
–
1
1
1
1
1
1
1
μs
Long calibration time
tZQCL
MIN
6
360
360
360
360
360
360
360
ns
Short calibration time
tZQCS
MIN
6
90
90
90
90
90
90
90
ns
Calibration RESET time
tZQRESET
MIN
3
50
50
50
50
50
50
50
ns
tDQSCK
MIN
–
2500
2500 2500 2500 2500 2500 2500
Initialization calibration time
READ
Parameters3
DQS output access time from
CK/CK#
ps
MAX
–
5500
5500 5500 5500 5500 5500 5500
DQSCK delta short
tDQSCKDS
MAX
–
330
380
450
540
1080
ps
4
DQSCK delta medium
tDQSCKDM
MAX
–
680
780
900
1050 1350 1800 1900
ps
5
DQSCK delta long
tDQSCKDL
MAX
–
920
1050 1200 1400 1800 2400
ps
6
tDQSQ
MAX
–
200
220
240
280
340
400
500
ps
Data-hold skew factor
tQHS
MAX
–
230
260
280
340
400
480
600
ps
DQS output HIGH pulse width
tQSH
MIN
–
tCH(abs)
DQS output LOW pulse width
tQSL
–
tCL(abs)
Data half period
tQHP
MIN
–
tQH
MIN
–
DQS-DQ skew
670
- 0.05
900
–
tCK
(avg)
MIN
- 0.05
tCK
(avg)
MIN
(tQSH, tQSL)
tCK
(avg)
DQ/DQS output hold time from
DQS
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129
tQHP
- tQHS
ps
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AC Timing
Table 87: AC Timing (Continued)
Notes 1–2 apply to all parameters and conditions. AC timing parameters must satisfy the tCK minimum conditions (in multiples of tCK) as well as the timing specifications when values for both are indicated.
Parameter
Symbol
Data Rate
Min/ tCK
Max Min 1066
933
800
667
533
400
333
Unit Notes
0.9
0.9
0.9
0.9
0.9
0.9
tCK
(avg)
7
tCK
8
READ preamble
tRPRE
MIN
–
READ postamble
tRPST
MIN
–
0.9
tCL(abs)
- 0.05
(avg)
DQS Low-Z from clock
tLZ(DQS)
MIN
tDQSCK
–
ps
MIN
–
tHZ(DQS)
MAX
–
tHZ(DQ)
MAX
–
DQ and DM input hold time (VREF
based)
tDH
MIN
–
210
235
270
350
430
480
600
ps
DQ and DM input setup time (VREF
based)
tDS
MIN
–
210
235
270
350
430
480
600
ps
DQ and DM input pulse width
tDIPW
MIN
–
0.35
0.35
0.35
0.35
0.35
0.35
0.35
tCK
Write command to first DQS latching transition
tDQSS
DQ Low-Z from clock
DQS High-Z from clock
DQ High-Z from clock
WRITE
tDQSCK(MIN)
(MIN) - 300
tLZ(DQ)
- (1.4 ×
tDQSCK
tDQSCK(MAX)
tQHS(MAX))
ps
(MAX) - 100
ps
+ (1.4 × tDQSQ(MAX))
ps
Parameters3
(avg)
MIN
–
0.75
0.75
0.75
0.75
0.75
0.75
0.75
tCK
(avg)
MAX
–
1.25
1.25
1.25
1.25
1.25
1.25
1.25
tCK
(avg)
DQS input high-level width
tDQSH
MIN
–
0.4
0.4
0.4
0.4
0.4
0.4
0.4
tCK
(avg)
DQS input low-level width
tDQSL
MIN
–
0.4
0.4
0.4
0.4
0.4
0.4
0.4
tCK
(avg)
DQS falling edge to CK setup time
tDSS
DQS falling edge hold time from
CK
tDSH
MIN
–
0.2
0.2
0.2
0.2
0.2
0.2
0.2
Write postamble
tWPST
MIN
–
0.4
0.4
0.4
0.4
0.4
0.4
0.4
tCK
(avg)
Write preamble
tWPRE
MIN
–
0.35
0.35
0.35
0.35
0.35
0.35
0.35
tCK
MIN
–
0.2
0.2
0.2
0.2
0.2
0.2
0.2
tCK
(avg)
tCK
(avg)
(avg)
CKE Input Parameters
tCKE
MIN
3
3
3
3
3
3
3
3
CKE input setup time
tISCKE
MIN
–
0.25
0.25
0.25
0.25
0.25
0.25
0.25
tCK
(avg)
9
CKE input hold time
tIHCKE
MIN
–
0.25
0.25
0.25
0.25
0.25
0.25
0.25
tCK
10
CKE minimum pulse width (HIGH
and LOW pulse width)
tCK
(avg)
(avg)
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AC Timing
Table 87: AC Timing (Continued)
Notes 1–2 apply to all parameters and conditions. AC timing parameters must satisfy the tCK minimum conditions (in multiples of tCK) as well as the timing specifications when values for both are indicated.
Parameter
Symbol
Data Rate
Min/ tCK
Max Min 1066
933
800
667
533
400
333
Unit Notes
Command Address Input Parameters3
Address and control input setup
time
tIS
MIN
–
220
250
290
370
460
600
740
ps
11
Address and control input hold
time
tIH
MIN
–
220
250
290
370
460
600
740
ps
11
Address and control input pulse
width
tIPW
MIN
–
0.40
0.40
0.40
0.40
0.40
0.40
0.40
tCK
(avg)
Boot Parameters (10 MHz–55 MHz)12, 13, 14
Clock cycle time
tCKb
MAX
–
100
100
100
100
100
100
100
18
18
18
18
18
18
18
ns
MIN
–
CKE input setup time
tISCKEb
MIN
–
2.5
2.5
2.5
2.5
2.5
2.5
2.5
ns
CKE input hold time
tIHCKEb
MIN
–
2.5
2.5
2.5
2.5
2.5
2.5
2.5
ns
Address and control input setup
time
tISb
MIN
–
1150
1150 1150 1150 1150 1150 1150
ps
Address and control input hold
time
tIHb
MIN
–
1150
1150 1150 1150 1150 1150 1150
ps
DQS output data access time from
CK/CK#
tDQSCKb
MIN
–
2.0
2.0
2.0
2.0
2.0
2.0
2.0
MAX
–
10.0
10.0
10.0
10.0
10.0
10.0
10.0
tDQSQb
MAX
–
1.2
1.2
1.2
1.2
1.2
1.2
1.2
ns
tQHSb
MAX
–
1.2
1.2
1.2
1.2
1.2
1.2
1.2
ns
MODE REGISTER WRITE
command period
tMRW
MIN
3
3
3
3
3
3
3
3
tCK
(avg)
MODE REGISTER READ
command period
tMRR
MIN
2
2
2
2
2
2
2
2
tCK
Data strobe edge to output data
edge
Data hold skew factor
ns
Mode Register Parameters
Core
(avg)
Parameters15
READ latency
RL
MIN
3
8
7
6
5
4
3
3
WRITE latency
WL
MIN
1
4
4
3
2
2
1
1
ACTIVATE-to-ACTIVATE
command period
tRC
MIN
–
tCK
(avg)
CKE minimum pulse width during
SELF REFRESH (low pulse width
during SELF REFRESH)
SELF REFRESH exit to next valid
command delay
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tRAS
tRAS
tCKESR
MIN
3
tXSR
MIN
2
131
15
+ tRPab (with all-bank precharge),
+ tRPpb (with per-bank precharge)
15
15
15
tRFCab
15
+ 10
15
15
tCK
(avg)
ns
17
ns
ns
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2Gb: x16, x32, x64 Automotive LPDDR2 SDRAM
AC Timing
Table 87: AC Timing (Continued)
Notes 1–2 apply to all parameters and conditions. AC timing parameters must satisfy the tCK minimum conditions (in multiples of tCK) as well as the timing specifications when values for both are indicated.
Data Rate
Min/ tCK
Max Min 1066
933
800
667
533
400
333
tXP
MIN
2
7.5
7.5
7.5
7.5
7.5
7.5
7.5
ns
CAS-to-CAS delay
tCCD
MIN
2
2
2
2
2
2
2
2
tCK
Internal READ to PRECHARGE
command delay
tRTP
MIN
2
7.5
7.5
7.5
7.5
7.5
7.5
7.5
ns
RAS-to-CAS delay
tRCD
Fast
3
15
15
15
15
15
15
15
ns
TYP
3
18
18
18
18
18
18
18
Fast
3
15
15
15
15
15
15
15
Parameter
Symbol
Exit power-down to next valid
command delay
Unit Notes
(avg)
Row precharge time (single bank)
tRPpb
TYP
3
18
18
18
18
18
18
18
Row precharge time (all banks)
tRPab
Fast
3
15
15
15
15
15
15
15
4-bank
TYP
3
18
18
18
18
18
18
18
tRPab
Fast
3
18
18
18
18
18
18
18
8-bank
TYP
3
21
21
21
21
21
21
21
Row precharge time (all banks)
tRAS
Row active time
ns
ns
ns
MIN
3
42
42
42
42
42
42
42
ns
MAX
–
70
70
70
70
70
70
70
μs
tWR
MIN
3
15
15
15
15
15
15
15
ns
Internal WRITE-to-READ
command delay
tWTR
MIN
2
7.5
7.5
7.5
7.5
7.5
10
10
ns
Active bank a to active bank b
tRRD
MIN
2
10
10
10
10
10
10
10
ns
Four-bank activate window
tFAW
MIN
8
50
50
50
50
50
50
60
ns
Minimum deep power-down time
tDPD
MIN
–
500
500
500
500
500
500
500
μs
tDQSCK
MAX
–
5620
6000 6000 6000 6000 6000 6000
ps
tRCD
(derated)
MIN
–
tRCD
tRC
MIN
–
tRC
MIN
–
tRAS
MIN
–
tRP
MIN
–
tRRD
WRITE recovery time
Temperature
tDQSCK
Derating16
derating
(derated)
Core timing temperature
derating
+ 1.875
+ 1.875
ns
ns
(derated)
tRAS
+ 1.875
ns
(derated)
tRP
+ 1.875
ns
(derated)
tRRD
(derated)
Notes:
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+ 1.875
ns
1. Frequency values are for reference only. Clock cycle time (tCK) is used to determine device capabilities.
132
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AC Timing
2. All AC timings assume an input slew rate of 1 V/ns.
3. READ, WRITE, and input setup and hold values are referenced to VREF.
4. tDQSCKDS is the absolute value of the difference between any two tDQSCK measurements (in a byte lane) within a contiguous sequence of bursts in a 160ns rolling window.
tDQSCKDS is not tested and is guaranteed by design. Temperature drift in the system is
2.0
75
–
175
–
2.0
57
–
170
–
1.5
50
–
167
–
1.0
38
–
163
–
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CA and CS# Setup, Hold, and Derating
Table 92: Required Time for Valid Transition – tVAC > VIH(AC) and < VIL(AC) (Continued)
tVAC
tVAC
at 300mV (ps)
at 220mV (ps)
Slew Rate
(V/ns)
Min
Max
Min
Max
0.9
34
–
162
–
0.8
29
–
161
–
0.7
22
–
159
–
0.6
13
–
155
–
0.5
0
–
150
–
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