MT46V64M4

256Mb: x4, x8, x16 DDR SDRAM Features Double Data Rate (DDR) SDRAM MT46V64M4 – 16 Meg x 4 x 4 banks MT46V32M8 – 8 Meg x 8 x 4 banks MT46V16M16 – 4 Meg x 16 x 4 banks Features • VDD = +2.5V ±0.2V, VDDQ = +2.5V ±0.2V • VDD = +2.6V ±0.1V, VDDQ = +2.6V ±0.1V (DDR400) • Bidirectional data strobe (DQS) transmitted/ received with data, that is, source-synchronous data capture (x16 has two – one per byte) • Internal, pipelined double-data-rate (DDR) architecture; two data accesses per clock cycle • Differential clock inputs (CK and CK#) • Commands entered on each positive CK edge • DQS edge-aligned with data for READs; centeraligned with data for WRITEs • DLL to align DQ and DQS transitions with CK • Four internal banks for concurrent operation • Data mask (DM) for masking write data (x16 has two – one per byte) • Programmable burst lengths (BL): 2, 4, or 8 • Auto refresh – 64ms, 8192-cycle(Commercial & Industrial) – 16ms, 8192-cycle (Automotive) • Self refresh (not available on AT devices) • Longer-lead TSOP for improved reliability (OCPL) • 2.5V I/O (SSTL_2-compatible) • Concurrent auto precharge option supported • tRAS lockout supported (tRAP = tRCD) Options Marking • Configuration – 64 Meg x 4 (16 Meg x 4 x 4 banks) 64M4 – 32 Meg x 8 (8 Meg x 8 x 4 banks) 32M8 – 16 Meg x 16 (4 Meg x 16 x 4 banks) 16M16 • Plastic package – OCPL – 66-pin TSOP TG – 66-pin TSOP (Pb-free) P • Plastic package FG1 – 60-ball FBGA (8mm x 14mm) BG1 – 60-ball FBGA (8mm x 14mm) (Pb-free) CV2 – 60-ball FBGA (8mm x 12.5mm) CY2 – 60-ball FBGA (8mm x 12.5mm) (Pb-free) • Timing – cycle time – 5ns @ CL = 3 (DDR400B) -5B – 6ns @ CL = 2.5 (DDR333) FBGA only -6 – 6ns @ CL = 2.5 (DDR333) TSOP only -6T -75E1 – 7.5ns @ CL = 2 (DDR266) -75Z1 – 7.5ns @ CL = 2 (DDR266A) -751 – 7.5ns @ CL = 2.5 (DDR266B) • Self refresh – Standard None – Low-power self refresh L • Temperature rating – Commercial (0°C to +70°C) None – Industrial (–40°C to +85°C) IT – Automotive (–40°C to +105°C) AT4 • Revision :G3 – x4, x8 :F3 – x16 – x4, x8, x16 :K Notes: 1. Only available on Revision F and G. 2. Only available on Revision K. 3. Not recommended for new designs. 4. Contact Micron for availability. PDF: 09005aef80768abb/Source: 09005aef82a95a3a 256Mb_DDR_x4x8x16_D1.fm - 256Mb DDR: Rev. O, Core DDR: Rev. B 1/09 EN 1 Micron Technology, Inc., reserves the right to change products or specifications without notice. ©2003 Micron Technology, Inc. All rights reserved. Products and specifications discussed herein are subject to change by Micron without notice. 256Mb: x4, x8, x16 DDR SDRAM Features Table 1: Key Timing Parameters CL = CAS (READ) latency; MIN clock rate with 50% duty cycle at CL = 2 (-75E, -75Z), CL = 2.5 (-6, -6T, -75), and CL = 3 (-5B) Clock Rate (MHz) Speed Grade -5B -6 6T -75E/-75Z -75 CL = 2 133 133 133 133 100 CL = 2.5 167 167 167 133 133 CL = 3 200 n/a n/a n/a n/a Data-Out Window Access Window DQS–DQ Skew 1.6ns ±0.70ns +0.40ns 2.1ns ±0.70ns +0.40ns 2.0ns ±0.70ns +0.45ns 2.5ns ±0.75ns +0.50ns 2.5ns ±0.75ns +0.50ns Table 2: Parameter Addressing 64 Meg x 4 16 Meg x 4 x 4 banks 8K 8K (A0–A12) 4 (BA0, BA1) 2K (A0–A9, A11) 32 Meg x 8 8 Meg x 8 x 4 banks 8K 8K (A0–A12) 4 (BA0, BA1) 1K (A0–A9) 16 Meg x 16 4 Meg x 16 x 4 banks 8K 8K (A0–A12) 4 (BA0, BA1) 512 (A0–A8) Configuration Refresh count Row address Bank address Column address Table 3: Marking -5B1 -6 -6T -75E -75Z -75 Speed Grade Compatibility PC3200 (3-3-3) PC2700 (2.5-3-3) PC2100 (2-2-2) PC2100 (2-3-3) PC2100 (2.5-3-3) PC1600(2-2-2) Yes – – – – – -5B Notes: Yes Yes Yes – – – -6/-6T Yes Yes Yes Yes – – -75E Yes Yes Yes Yes Yes – -75Z Yes Yes Yes Yes Yes Yes -75 Yes Yes Yes Yes Yes Yes -75 1. The -5B device is backward compatible with all slower speed grades. The voltage range of -5B device operating at slower speed grades is VDD = VDDQ = 2.5V ± 0.2V. PDF: 09005aef80768abb/Source: 09005aef82a95a3a 256Mb_DDR_x4x8x16_D1.fm - 256Mb DDR: Rev. O, Core DDR: Rev. B 1/09 EN 2 Micron Technology, Inc., reserves the right to change products or specifications without notice. ©2003 Micron Technology, Inc. All rights reserved. 256Mb: x4, x8, x16 DDR SDRAM Features Figure 1: 256Mb DDR SDRAM Part Numbers Example Part Number: M T 4 6 V 1 6 M 1 6 P - 6 T: F MT46V Configuration Package Speed : Sp. Temp. Revision Op. Configuration 64 Meg x 4 32 Meg x 8 16 Meg x 16 Package 400-mil TSOP 400-mil TSOP (Pb-free) 8mm x 14mm FBGA 8mm x 14mm FBGA (Pb-free) 8mm x 12.5mm FBGA 8mm x 12.5mm FBGA (Pb-free) TG P FG BG CV CY IT AT Revision 64M4 32M8 16M16 :F x16 :G x4, x8 :K x4, x8, x16 Operating Temp. Commercial Industrial Automotive Special Options Standard L Low power -5B -6 -6T -75E -75Z -75 Speed Grade tCK = 5ns, CL = 3 tCK = 6ns, CL = 2.5 tCK = 6ns, CL = 2.5 tCK = 7.5ns, CL = 2 tCK = 7.5ns, CL = 2 tCK = 7.5ns, CL = 2.5 FBGA Part Marking System Due to space limitations, FBGA-packaged components have an abbreviated part marking that is different from the part number. For a quick conversion of an FBGA code, see the FBGA Part Marking Decoder on Micron’s Web site: www.micron.com. PDF: 09005aef80768abb/Source: 09005aef82a95a3a 256Mb_DDR_x4x8x16_D1.fm - 256Mb DDR: Rev. O, Core DDR: Rev. B 1/09 EN 3 Micron Technology, Inc., reserves the right to change products or specifications without notice. ©2003 Micron Technology, Inc. All rights reserved. 256Mb: x4, x8, x16 DDR SDRAM Table of Contents Table of Contents State Diagram. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5 Functional Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6 General Notes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6 Automotive Tempature. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7 Functional Block Diagrams. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .8 Pin and Ball Assignments and Descriptions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .10 Package Dimensions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .14 Electrical Specifications – DC and AC. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .20 Notes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .37 Commands . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .45 DESELECT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .49 NO OPERATION (NOP). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .49 LOAD MODE REGISTER (LMR) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .49 ACTIVE (ACT) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .50 READ . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .51 WRITE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .52 PRECHARGE (PRE) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .53 BURST TERMINATE (BST) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .53 AUTO REFRESH (AR). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .53 SELF REFRESH . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .53 Operations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .54 INITIALIZATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .54 REGISTER DEFINITION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .57 ACTIVE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .61 READ . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .62 WRITE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .74 PRECHARGE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .87 AUTO REFRESH . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .89 SELF REFRESH . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .90 Power-down (CKE Not Active) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .92 PDF: 09005aef80768abb/Source: 09005aef82a95a3a 256Mb_DDRTOC.fm - 256Mb DDR: Rev. O, Core DDR: Rev. B 1/09 EN 4 Micron Technology, Inc., reserves the right to change products or specifications without notice. ©2003 Micron Technology, Inc. All rights reserved. 256Mb: x4, x8, x16 DDR SDRAM State Diagram State Diagram Figure 2: Simplified State Diagram Power applied Power on PRE Precharge all banks LMR Self refresh REFS LMR REFSX Idle REFA all banks precharged CKEL CKEH MR EMR Auto refresh Active powerdown ACT CKE HIGH Precharge powerdown CKE LOW Row active WRITE WRITE WRITE A Write READ A READ READ BST READ Burst stop Read WRITE A PRE READ A PRE PRE READ A Write A Read A PRE Precharge PREALL Automatic sequence Command sequence ACT = ACTIVE BST = BURST TERMINATE CKEH = Exit power-down CKEL = Enter power-down EMR = Extended mode register LMR = LOAD MODE REGISTER MR = Mode register PRE = PRECHARGE PREALL = PRECHARGE all banks READ A = READ with auto precharge REFA = AUTO REFRESH REFS = Enter self refresh REFSX = Exit self refresh WRITE A = WRITE with auto precharge Note: This diagram represents operations within a single bank only and does not capture concurrent operations in other banks. PDF: 09005aef80768abb/Source: 09005aef82a95a3a DDR_x4x8x16_Core1.fm - 256Mb DDR: Rev. O, Core DDR: Rev. B 1/09 EN 4 Micron Technology, Inc., reserves the right to change products or specifications without notice. ©2003 Micron Technology, Inc. All rights reserved. 256Mb: x4, x8, x16 DDR SDRAM Functional Description Functional Description The DDR SDRAM uses a double data rate architecture to achieve high-speed operation. The double data rate architecture is essentially a 2n-prefetch architecture with an interface designed to transfer two data words per clock cycle at the I/O pins. A single read or write access for the DDR SDRAM effectively consists of a single 2n-bit-wide, one-clockcycle data transfer at the internal DRAM core and two corresponding n-bit-wide, onehalf-clock-cycle data transfers at the I/O pins. A bidirectional data strobe (DQS) is transmitted externally, along with data, for use in data capture at the receiver. DQS is a strobe transmitted by the DDR SDRAM during READs and by the memory controller during WRITEs. DQS is edge-aligned with data for READs and center-aligned with data for WRITEs. The x16 offering has two data strobes, one for the lower byte and one for the upper byte. The DDR SDRAM operates from a differential clock (CK and CK#); the crossing of CK going HIGH and CK# going LOW will be referred to as the positive edge of CK. Commands (address and control signals) are registered at every positive edge of CK. Input data is registered on both edges of DQS, and output data is referenced to both edges of DQS, as well as to both edges of CK. Read and write accesses to the DDR SDRAM are burst oriented; accesses start at a selected location and continue for a programmed number of locations in a programmed sequence. Accesses begin with the registration of an ACTIVE command, which may then be followed by a READ or WRITE command. The address bits registered coincident with the ACTIVE command are used to select the bank and row to be accessed. The address bits registered coincident with the READ or WRITE command are used to select the bank and the starting column location for the burst access. The DDR SDRAM provides for programmable READ or WRITE burst lengths of 2, 4, or 8 locations. An auto precharge function may be enabled to provide a self-timed row precharge that is initiated at the end of the burst access. As with standard SDR SDRAMs, the pipelined, multibank architecture of DDR SDRAMs allows for concurrent operation, thereby providing high effective bandwidth by hiding row precharge and activation time. An auto refresh mode is provided, along with a power-saving power-down mode. All inputs are compatible with the JEDEC standard for SSTL_2. All full-drive option outputs are SSTL_2, Class II compatible. General Notes • The functionality and the timing specifications discussed in this data sheet are for the DLL-enabled mode of operation. • Throughout the data sheet, the various figures and text refer to DQs as “DQ.” The DQ term is to be interpreted as any and all DQ collectively, unless specifically stated otherwise. Additionally, the x16 is divided into two bytes, the lower byte and upper byte. For the lower byte (DQ0–DQ7) DM refers to LDM and DQS refers to LDQS. For the upper byte (DQ8–DQ15) DM refers to UDM and DQS refers to UDQS. • Complete functionality is described throughout the document and any page or diagram may have been simplified to convey a topic and may not be inclusive of all requirements. • Any specific requirement takes precedence over a general statement. PDF: 09005aef80768abb/Source: 09005aef82a95a3a DDR_x4x8x16_Core1.fm - 256Mb DDR: Rev. O, Core DDR: Rev. B 1/09 EN 5 Micron Technology, Inc., reserves the right to change products or specifications without notice. ©2003 Micron Technology, Inc. All rights reserved. 256Mb: x4, x8, x16 DDR SDRAM Functional Description Automotive Tempature The automotive temperature (AT) option adheres to the following specifications: • 16ms refresh rate • Self refresh not supported • Ambient and case temperatures cannot be less than –40°C or greater than +105°C PDF: 09005aef80768abb/Source: 09005aef82a95a3a DDR_x4x8x16_Core1.fm - 256Mb DDR: Rev. O, Core DDR: Rev. B 1/09 EN 6 Micron Technology, Inc., reserves the right to change products or specifications without notice. ©2003 Micron Technology, Inc. All rights reserved. 256Mb: x4, x8, x16 DDR SDRAM Functional Block Diagrams Functional Block Diagrams The 256Mb DDR SDRAM is a high-speed CMOS, dynamic random-access memory containing 268,435,456 bits. It is internally configured as a 4-bank DRAM. Figure 3: 64 Meg x 4 Functional Block Diagram CKE CK# CK CS# WE# CAS# RAS# Command decode Control logic Bank 3 Bank 2 Bank 1 Mode registers Refresh counter 13 Rowaddress MUX 13 Bank 0 rowaddress latch and decoder Bank 0 memory array (8,192 x 1,024 x 8) 4 8 4 CK 15 13 8192 Data DLL Sense amplifiers 8192 READ latch MUX 4 Drivers DQS generator Column 0 1 DQ0–DQ3 2 A0–A12, BA0, BA1 Address register Bank control logic 1024 (x8) 8 I/O gating DM mask logic 8 1 Input registers 1 1 1 2 4 8 4 4 4 4 1 DQS DQS 15 Mask WRITE FIFO and drivers CK out CK in 2 Rcvrs DM Column decoder Columnaddress counter/ latch 10 Data 11 CK 1 Column 0 1 PDF: 09005aef80768abb/Source: 09005aef82a95a3a 256Mb_DDR_x4x8x16_D2.fm - 256Mb DDR: Rev. O, Core DDR: Rev. B 1/09 EN 8 Micron Technology, Inc., reserves the right to change products or specifications without notice. ©2003 Micron Technology, Inc. All rights reserved. 256Mb: x4, x8, x16 DDR SDRAM Functional Block Diagrams Figure 4: 32 Meg x 8 Functional Block Diagram CKE CK# CK CS# WE# CAS# RAS# CONTROL LOGIC BANK3 BANK2 BANK1 COMMAND DECODE MODE REGISTERS REFRESH 13 COUNTER 15 13 ROWADDRESS MUX 13 BANK0 ROWADDRESS LATCH & DECODER 8192 BANK0 MEMORY ARRAY (8192 x 512 x 16) 8 16 READ LATCH MUX 8 DQS GENERATOR COL0 16 1 MASK WRITE FIFO & DRIVERS CK Out CK In 1 2 8 16 8 DATA 8 8 INPUT REGISTERS 1 8 CK DATA DLL SENSE AMPLIFIERS 8192 DRVRS 1 DQ0–DQ7 2 A0–A12, BA0, BA1 ADDRESS REGISTER BANK CONTROL LOGIC I/O GATING DM MASK LOGIC DQS DQS 1 1 RCVRS 8 DM 15 2 512 (x16) 16 COLUMN DECODER COLUMNADDRESS COUNTER/ LATCH 9 10 CK COL0 1 1 Figure 5: 16 Meg x 16 Functional Block Diagram CKE CK# CK CS# WE# CAS# RAS# CONTROL LOGIC BANK3 BANK2 REFRESH COUNTER 13 BANK1 COMMAND DECODE MODE REGISTERS 15 13 ROWADDRESS MUX 13 BANK0 ROWADDRESS LATCH & DECODER 8192 BANK0 MEMORY ARRAY (8,192 x 256 x 32) 16 32 READ LATCH MUX 16 DQS GENERATOR COL0 16 CK DATA DLL SENSE AMPLIFIERS 8192 DRVRS 2 DQ0–DQ15 DQS LDQS UDQS 2 2 4 16 32 16 DATA 16 16 16 RCVRS LDM, UDM 2 2 A0–A12, BA0, BA1 ADDRESS REGISTER BANK CONTROL LOGIC I/O GATING DM MASK LOGIC 32 2 MASK WRITE FIFO & DRIVERS CK Out CK In INPUT REGISTERS 2 15 2 256 (x32) 32 COLUMN DECODER COLUMNADDRESS COUNTER/ LATCH 8 9 CK COL0 2 1 PDF: 09005aef80768abb/Source: 09005aef82a95a3a 256Mb_DDR_x4x8x16_D2.fm - 256Mb DDR: Rev. O, Core DDR: Rev. B 1/09 EN 9 Micron Technology, Inc., reserves the right to change products or specifications without notice. ©2003 Micron Technology, Inc. All rights reserved. 256Mb: x4, x8, x16 DDR SDRAM Pin and Ball Assignments and Descriptions Pin and Ball Assignments and Descriptions Figure 6: 66-Pin TSOP Pin Assignments (Top View) x4 x16 x8 VDD VDD VDD NF DQ0 DQ0 VDDQ VDDQ VDDQ NC DQ1 NC DQ0 DQ1 DQ2 VSSQ VSSQ VSSQ NC DQ3 NC NF DQ2 DQ4 VDDQ VDDQ VDDQ NC NC DQ5 DQ1 DQ3 DQ6 VSSQ VSSQ VSSQ NC DQ7 NC NC NC NC VDDQ VDDQ VDDQ NC NC LDQS NC NC NC VDD VDD VDD DNU DNU DNU NC NC LDM WE# WE# WE# CAS# CAS# CAS# RAS# RAS# RAS# CS# CS# CS# NC NC NC BA0 BA0 BA0 BA1 BA1 BA1 A10/AP A10/AP A10/AP A0 A0 A0 A1 A1 A1 A2 A2 A2 A3 A3 A3 VDD VDD VDD x16 VSS DQ15 VSSQ DQ14 DQ13 VDDQ DQ12 DQ11 VSSQ DQ10 DQ9 VDDQ DQ8 NC VSSQ UDQS DNU VREF VSS UDM CK# CK CKE NC A12 A11 A9 A8 A7 A6 A5 A4 VSS x8 VSS DQ7 VSSQ NC DQ6 VDDQ NC DQ5 VSSQ NC DQ4 VDDQ NC NC VSSQ DQS DNU VREF VSS DM CK# CK CKE NC A12 A11 A9 A8 A7 A6 A5 A4 VSS x4 VSS NF VSSQ NC DQ3 VDDQ NC NF VSSQ NC DQ2 VDDQ NC NC VSSQ DQS DNU VREF VSS DM CK# CK CKE NC A12 A11 A9 A8 A7 A6 A5 A4 VSS 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 28 29 30 31 32 33 66 65 64 63 62 61 60 59 58 57 56 55 54 53 52 51 50 49 48 47 46 45 44 43 42 41 40 39 38 37 36 35 34 PDF: 09005aef80768abb/Source: 09005aef82a95a3a 256Mb_DDR_x4x8x16_D2.fm - 256Mb DDR: Rev. O, Core DDR: Rev. B 1/09 EN 10 Micron Technology, Inc., reserves the right to change products or specifications without notice. ©2003 Micron Technology, Inc. All rights reserved. 256Mb: x4, x8, x16 DDR SDRAM Pin and Ball Assignments and Descriptions Figure 7: 60-Ball FBGA Ball Assignments (Top View) x4 (Top View) 1 2 3 4 5 A B C D E F G H J K L M 6 7 8 9 NF VSSQ VSS NC VDDQ DQ3 NC VSSQ NF NC VDDQ DQ2 NC VSSQ DQS VSS DM VREF CK CK# A12 CKE A11 A9 A8 A7 A6 A5 A4 VSS VDD DQ0 NF DQ1 NC NC WE# RAS# BA1 A0 A2 VDD NF VDDQ VSSQ NC VDDQ NC VSSQ NC VDDQ NC VDD DNU CAS# CS# BA0 A10 A1 A3 x8 (Top View) 1 2 3 4 5 A B C D E F G H J K L M 6 7 8 9 VSSQ DQ7 NC VDDQ NC VSSQ NC VDDQ NC VSSQ VSS VREF CK A12 A11 A8 A6 A4 VSS DQ6 DQ5 DQ4 DQS DM CK# CKE A9 A7 A5 VSS VDD DQ1 DQ2 DQ3 NC NC WE# RAS# BA1 A0 A2 VDD DQ0 VDDQ VSSQ NC VDDQ NC VSSQ NC VDDQ NC VDD DNU CAS# CS# BA0 A10 A1 A3 x16 (Top View) 1 2 3 4 5 A B C D E F G H J K L M 6 7 8 9 VSSQ DQ14 DQ12 DQ10 DQ8 VREF DQ15 VDDQ VSSQ VDDQ VSSQ VSS CK A12 A11 A8 A6 A4 VSS DQ13 DQ11 DQ9 UDQS UDM CK# CKE A9 A7 A5 VSS VDD DQ2 DQ4 DQ6 LDQS LDM WE# RAS# BA1 A0 A2 VDD DQ0 VSSQ VDDQ VSSQ VDDQ VDD CAS# CS# BA0 A10 A1 A3 VDDQ DQ1 DQ3 DQ5 DQ7 DNU PDF: 09005aef80768abb/Source: 09005aef82a95a3a 256Mb_DDR_x4x8x16_D2.fm - 256Mb DDR: Rev. O, Core DDR: Rev. B 1/09 EN 11 Micron Technology, Inc., reserves the right to change products or specifications without notice. ©2003 Micron Technology, Inc. All rights reserved. 256Mb: x4, x8, x16 DDR SDRAM Pin and Ball Assignments and Descriptions Table 4: FBGA Numbers K7, L8, L7, M8, M2, L3, L2, K3, K2, J3, K8, J2, H2 Pin and Ball Descriptions TSOP Numbers 29, 30, 31, 32, 35, 36, 37, 38, 39, 40, 28 41, 42 Symbol A0, A1, A2, A3, A4, A5, A6, A7, A8, A9, A10, A11, A12 Type Input Description Address inputs: Provide the row address for ACTIVE commands, and the column address and auto precharge bit (A10) for READ/ WRITE commands, to select one location out of the memory array in the respective bank. A10 sampled during a PRECHARGE command determines whether the PRECHARGE applies to one bank (A10 LOW, bank selected by BA0, BA1) or all banks (A10 HIGH). The address inputs also provide the op-code during a LOAD MODE REGISTER command. Bank address inputs: BA0 and BA1 define to which bank an ACTIVE, READ, WRITE, or PRECHARGE command is being applied. BA0 and BA1 also define which mode register (mode register or extended mode register) is loaded during the LOAD MODE REGISTER (LMR) command. Clock: CK and CK# are differential clock inputs. All address and control input signals are sampled on the crossing of the positive edge of CK and the negative edge of CK#. Output data (DQ and DQS) is referenced to the crossings of CK and CK#. Clock enable: CKE HIGH activates and CKE LOW deactivates the internal clock, input buffers, and output drivers. Taking CKE LOW provides PRECHARGE POWER-DOWN and SELF REFRESH operations (all banks idle) or ACTIVE POWER-DOWN (row ACTIVE in any bank). CKE is synchronous for POWER-DOWN entry and exit and for SELF REFRESH entry. CKE is asynchronous for SELF REFRESH exit and for disabling the outputs. CKE must be maintained HIGH throughout read and write accesses. Input buffers (excluding CK, CK#, and CKE) are disabled during POWER- DOWN. Input buffers (excluding CKE) are disabled during SELF REFRESH. CKE is an SSTL_2 input but will detect an LVCMOS LOW level after VDD is applied and until CKE is first brought HIGH, after which it becomes a SSTL_2 input only. Chip select: CS# enables (registered LOW) and disables (registered HIGH) the command decoder. All commands are masked when CS# is registered HIGH. CS# provides for external bank selection on systems with multiple banks. CS# is considered part of the command code. Input data mask: DM is an input mask signal for write data. Input data is masked when DM is sampled HIGH along with that input data during a WRITE access. DM is sampled on both edges of DQS. Although DM pins are input-only, the DM loading is designed to match that of DQ and DQS pins. For the x16, LDM is DM for DQ0– DQ7 and UDM is DM for DQ8–DQ15. Pin 20 is a NC on x4 and x8. Command inputs: RAS#, CAS#, and WE# (along with CS#) define the command being entered. Data input/output: Data bus for x16. J8, J7 26, 27 BA0, BA1 Input G2, G3 45, 46 CK, CK# Input H3 44 CKE Input H8 24 CS# Input F3 F7, F3 47 20, 47 DM LDM, UDM Input H7, G8, G7 A8, B9, B7, C9, C7, D9, D7, E9, E1, D3, D1, C3, C1, B3, B1, A2 A8, B7, C7, D7, D3, C3, B3, A2 23, 22, 21 2, 4, 5, 7, 8, 10, 11, 13, 54, 56, 57, 59, 60, 62, 63, 65 2, 5, 8, 11, 56, 59, 62, 65 RAS#, CAS#, WE# DQ0–DQ2 DQ3–DQ5 DQ6–DQ8 DQ9–DQ11 DQ12–DQ14 DQ15 DQ0–DQ2 DQ3–DQ5 DQ6, DQ7 Input I/O I/O Data input/output: Data bus for x8. PDF: 09005aef80768abb/Source: 09005aef82a95a3a 256Mb_DDR_x4x8x16_D2.fm - 256Mb DDR: Rev. O, Core DDR: Rev. B 1/09 EN 12 Micron Technology, Inc., reserves the right to change products or specifications without notice. ©2003 Micron Technology, Inc. All rights reserved. 256Mb: x4, x8, x16 DDR SDRAM Pin and Ball Assignments and Descriptions Table 4: FBGA Numbers B7, D7, D3, B3 E3 E7 E3 F8, M7, A7 B2, D2, C8, E8, A9 A3, F2, M3 A1, C2, E2, B8, D8 F1 – B1, B9, C1, C9, D1, D9, E1, E7, E9, F7 B1, B9, C1, C9, D1, D9, E1, E7, E9, F7, A2, A8, C3, C7 F9 Pin and Ball Descriptions (continued) TSOP Numbers 5, 11, 56, 62 51 16 51 1, 18, 33 3, 9, 15, 55, 61 34, 48, 66 6, 12, 52, 58, 64 49 14, 17, 25, 43, 53 4, 7, 10, 13, 14, 16, 17, 20, 25, 43, 53, 54, 57, 60, 63 4, 7, 10, 13, 14, 16, 17, 20, 25, 43, 53, 54, 57, 60, 63 2, 8, 59, 65 19, 50 Symbol DQ0–DQ2 DQ3 DQS LDQS UDQS Type I/O I/O Description Data input/output: Data bus for x4. Data strobe: Output with read data, input with write data. DQS is edge-aligned with read data, centered in write data. It is used to capture data. For the x16, LDQS is DQS for DQ0–DQ7 and UDQS is DQS for DQ8–DQ15. Pin 16 (E7) is NC on x4 and x8. Power supply. DQ power supply: Isolated on the die for improved noise immunity. Ground. DQ ground: Isolated on the die for improved noise immunity. SSTL_2 reference voltage. No connect for x16: These pins should be left unconnected. No connect for x8: These pins should be left unconnected. VDD VDDQ VSS VSSQ VREF NC NC Supply Supply Supply Supply Supply – – NC – No connect for x4: These pins should be left unconnected. NF DNU – – No function for x4: These pins should be left unconnected. Do not use: Must float to minimize noise on VREF. Table 5: Reserved NC Pin Descriptions NC pins not listed may also be reserved for other uses; this table defines NC pins of importance Symbol A13 Type Input Description Address input A13 for 1Gb devices. TSOP Numbers 17 PDF: 09005aef80768abb/Source: 09005aef82a95a3a 256Mb_DDR_x4x8x16_D2.fm - 256Mb DDR: Rev. O, Core DDR: Rev. B 1/09 EN 13 Micron Technology, Inc., reserves the right to change products or specifications without notice. ©2003 Micron Technology, Inc. All rights reserved. 256Mb: x4, x8, x16 DDR SDRAM Package Dimensions Package Dimensions Figure 8: 66-Pin Plastic TSOP (400 mil) 22.22 ± 0.08 0.71 0.65 TYP 0.32 ±0.075 TYP 0.10 (2X) SEE DETAIL A 11.76 ± 0.20 10.16 ±0.08 PIN #1 ID +0.03 0.15 –0.02 GAGE PLANE 0.25 0.10 0.10 1.20 MAX +0.10 –0.05 0.80 TYP 0.50 ±0.10 DETAIL A Notes: 1. All dimensions in millimeters. 2. Package width and length do not include mold protrusion; allowable mold protrusion is 0.25mm per side. PDF: 09005aef80768abb/Source: 09005aef82a95a3a 256Mb_DDR_x4x8x16_D2.fm - 256Mb DDR: Rev. O, Core DDR: Rev. B 1/09 EN 14 Micron Technology, Inc., reserves the right to change products or specifications without notice. ©2003 Micron Technology, Inc. All rights reserved. 256Mb: x4, x8, x16 DDR SDRAM Package Dimensions Figure 9: 60-Ball FBGA (8mm x 14mm)1 0.85 ±0.1 Seating plane 0.12 A A 60X Ø0.45 Solder ball material: SAC305. Dimensions apply to solder balls postreflow on Ø0.33 NSMD ball pads. 8 ±0.15 98 7 3 21 Ball A1 ID Ball A1 ID A B C D E 11 CTR F G H J K L 1 TYP M 14 ±0.15 0.8 TYP 6.4 CTR 1.2 MAX 0.25 MIN Notes: 1. Package only available in Die Revision F and G. 2. All dimensions are in millimeters. 3. Topside part marking decoder can be found on Micron’s Web site. PDF: 09005aef80768abb/Source: 09005aef82a95a3a 256Mb_DDR_x4x8x16_D2.fm - 256Mb DDR: Rev. O, Core DDR: Rev. B 1/09 EN 15 Micron Technology, Inc., reserves the right to change products or specifications without notice. ©2003 Micron Technology, Inc. All rights reserved. 256Mb: x4, x8, x16 DDR SDRAM Package Dimensions Figure 10: 60-Ball FBGA (8mm x 12.5mm)1 0.8 ±0.1 Seating plane 0.12 A A 60X Ø0.45 Solder ball material: eutectic or SAC305. Dimensions apply to solder balls postreflow on Ø0.33 NSMD ball pads. 987 321 A B C D E F G H J Ball A1 ID Ball A1 ID 11 CTR 12.5 ±0.15 1 TYP K L M 0.8 TYP 6.4 CTR 8 ±0.15 1.20 MAX 0.25 MIN Notes: 1. Package only available in Die Revision K. 2. All dimensions are in millimeters. 3. Topside part marking decoder can be found on Micron’s Web site. PDF: 09005aef80768abb/Source: 09005aef82a95a3a 256Mb_DDR_x4x8x16_D2.fm - 256Mb DDR: Rev. O, Core DDR: Rev. B 1/09 EN 16 Micron Technology, Inc., reserves the right to change products or specifications without notice. ©2003 Micron Technology, Inc. All rights reserved. 256Mb: x4, x8, x16 DDR SDRAM Electrical Specifications – IDD Electrical Specifications – IDD Table 6: IDD Specifications and Conditions (x4, x8: -5B, -6, -6T, -75E, -7Z, -75) - Die Revision F Only VDDQ = +2.6V ±0.1V, VDD = +2.6V ±0.1V (-5B); VDDQ = +2.5V ±0.2V, VDD = +2.5V ±0.2V (-6, -6T, -75E, -7Z, -75); 0°C ≤ TA ≤ +70°C; Notes: 1–5, 11, 13, 15, 47; Notes appear on pages 35–40; See also Table 9 on page 18 Parameter/Condition = (MIN); Operating one-bank precharge current: CK = tCK (MIN); DQ, DM, and DQS inputs changing once per clock cycle; Address and control inputs changing once every two clock cycles Operating one-bank active-read-precharge current: Burst = 4; tRC = tRC (MIN); tCK = tCK (MIN); IOUT = 0mA; Address and control inputs changing once per clock cycle Precharge power-down standby current: All banks idle; Power-down mode; tCK = tCK (MIN); CKE = LOW Idle standby current: CS# = HIGH; All banks are idle; tCK = tCK (MIN); CKE = HIGH; Address and other control inputs changing once per clock cycle; VIN = VREF for DQ, DQS, and DM Active power-down standby current: One bank active; Power-down mode; tCK = tCK (MIN); CKE = LOW Active standby current: CS# = HIGH; CKE = HIGH; One bank active; tRC = tRAS (MAX); tCK = tCK (MIN); DQ, DM, and DQS inputs changing twice per clock cycle; Address and other control inputs changing once per clock cycle Operating burst read current: Burst = 2; Continuous burst reads; One bank active; Address and control inputs changing once per clock cycle; tCK = tCK (MIN); IOUT = 0mA Operating burst write current: Burst = 2; Continuous burst writes; One bank active; Address and control inputs changing once per clock cycle; tCK = tCK (MIN); DQ, DM, and DQS inputs changing twice per clock cycle tREFC = tRFC (MIN) Auto refresh burst current: tREFC =7.8µs Self refresh current: CKE ≤ 0.2V Standard Low power (L) Operating bank interleave read current: Four-bank interleaving READs (burst = 4) with auto precharge; tRC = minimum tRC allowed; tCK = tCK (MIN); Address and control inputs change only during ACTIVE, READ, or WRITE commands t tRC tRC Symbol -5B 135 -6/6T -75E -75Z 125 125 120 -75 120 Units mA Notes 23, 48 IDD0 IDD1 170 170 160 145 145 mA 23, 48 IDD2P IDD2F 4 60 4 50 4 45 4 45 4 45 mA mA 24, 33 51 IDD3P 40 70 30 60 25 50 25 50 30 50 mA mA 24, 33 23 IDD3N IDD4R 200 175 150 150 150 mA 23, 48 IDD4W 195 175 150 150 150 mA 23 IDD5 IDD5A IDD6 IDD6A IDD7 260 6 4 2 470 255 6 4 2 410 235 6 4 2 350 235 6 4 2 350 245 6 4 2 365 mA mA mA mA mA 50 28, 50 12 12 23, 49 PDF: 09005aef80768abb/Source: 09005aef82a95a3a 256Mb_DDR_x4x8x16_D2.fm - 256Mb DDR: Rev. O, Core DDR: Rev. B 1/09 EN 17 Micron Technology, Inc., reserves the right to change products or specifications without notice. ©2003 Micron Technology, Inc. All rights reserved. 256Mb: x4, x8, x16 DDR SDRAM Electrical Specifications – IDD Table 7: IDD Specifications and Conditions (x16: -5B, -6, -6T, -75E, -75Z, -75) - Die Revision G Only VDDQ = +2.6V ±0.1V, VDD = +2.6V ±0.1V (-5B); VDDQ = +2.5V ±0.2V, VDD = +2.5V ±0.2V (-6, -6T, -75E, -7Z, -75); 0°C ≤ TA ≤ +70°C; Notes: 1–5, 11, 13, 15, 47; Notes appear on pages 35–40; See also Table 9 on page 18 Parameter/Condition = (MIN); Operating one-bank precharge current: t CK = tCK (MIN); DQ, DM, and DQS inputs changing once per clock cycle; Address and control inputs changing once every two clock cycles Operating one-bank active-read-precharge current: Burst = 4; tRC = tRC (MIN); tCK = tCK (MIN); IOUT = 0mA; Address and control inputs changing once per clock cycle Precharge power-down standby current: All banks idle; Power-down mode; tCK = tCK (MIN); CKE = LOW Idle standby current: CS# = HIGH; All banks are idle; tCK = tCK (MIN); CKE = HIGH; Address and other control inputs changing once per clock cycle; VIN = VREF for DQ, DQS, and DM Active power-down standby current: One bank active; Power-down mode; tCK = tCK (MIN); CKE = LOW Active standby current: CS# = HIGH; CKE = HIGH; One bank active; tRC = tRAS (MAX); tCK = tCK (MIN); DQ, DM, and DQS inputs changing twice per clock cycle; Address and other control inputs changing once per clock cycle Operating burst read current: Burst = 2; Continuous burst reads; One bank active; Address and control inputs changing once per clock cycle; tCK = tCK (MIN); IOUT = 0mA Operating burst write current: Burst = 2; Continuous burst writes; One bank active; Address and control inputs changing once per clock cycle; tCK = tCK (MIN); DQ, DM, and DQS inputs changing twice per clock cycle tREFC = tRFC (MIN) Auto refresh burst current: tREFC = 7.8µs Self refresh current: CKE ≤ 0.2V Standard Low power (L) Operating bank interleave read current: Four-bank interleaving READs (burst = 4) with auto precharge; tRC = minimum tRC allowed; tCK = tCK (MIN); Address and control inputs change only during ACTIVE, READ, or WRITE commands tRC tRC Symbol -5B 135 -6/6T -75E -75Z 125 125 120 -75 120 Units mA Notes 23, 48 IDD0 IDD1 185 180 170 155 155 mA 23, 48 IDD2P IDD2F 4 60 4 50 4 45 4 45 4 45 mA mA 24, 33 51 IDD3P 40 70 30 60 25 50 25 50 30 50 mA mA 24, 33 23 IDD3N IDD4R 260 220 185 185 185 mA 23, 48 IDD4W 215 195 160 160 160 mA 23 IDD5 IDD5A IDD6 IDD6A IDD7 260 6 4 2 510 255 6 4 2 440 235 6 4 2 380 235 6 4 2 380 245 6 4 2 400 mA mA mA mA mA 50 28, 50 12 12 23, 49 PDF: 09005aef80768abb/Source: 09005aef82a95a3a 256Mb_DDR_x4x8x16_D2.fm - 256Mb DDR: Rev. O, Core DDR: Rev. B 1/09 EN 18 Micron Technology, Inc., reserves the right to change products or specifications without notice. ©2003 Micron Technology, Inc. All rights reserved. 256Mb: x4, x8, x16 DDR SDRAM Electrical Specifications – IDD Table 8: IDD Specifications and Conditions (x4, x8, x16: -5B, -6, -6T) - Die Revision K Only VDDQ = +2.6V ±0.1V, VDD = +2.6V ±0.1V (-5B); VDDQ = +2.5V ±0.2V, VDD = +2.5V ±0.2V (-6, -6T); 0°C ≤ TA ≤ +70°C; Notes: 1–5, 11, 13, 15, 47; Notes appear on pages 35–40; See also Table 9 on page 18 Parameter/Condition = (MIN); Operating one-bank precharge current: CK = tCK (MIN); DQ, DM, and DQS inputs changing once per clock cycle; Address and control inputs changing once every two clock cycles Operating one-bank active-read-precharge current: Burst = 4; t RC = tRC (MIN); tCK = tCK (MIN); IOUT = 0mA; Address and control inputs changing once per clock cycle Precharge power-down standby current: All banks idle; Powerdown mode; tCK = tCK (MIN); CKE = LOW Idle standby current: CS# = HIGH; All banks are idle; tCK = tCK (MIN); CKE = HIGH; Address and other control inputs changing once per clock cycle; VIN = VREF for DQ, DQS, and DM Active power-down standby current: One bank active; Powerdown mode; tCK = tCK (MIN); CKE = LOW Active standby current: CS# = HIGH; CKE = HIGH; One bank active; tRC = tRAS (MAX); tCK = tCK (MIN); DQ, DM, and DQS inputs changing twice per clock cycle; Address and other control inputs changing once per clock cycle Operating burst read current: Burst = 2; Continuous burst reads; One bank active; Address and control inputs changing once per clock cycle; tCK = tCK (MIN); IOUT = 0mA Operating burst write current: Burst = 2; Continuous burst writes; One bank active; Address and control inputs changing once per clock cycle; tCK = tCK (MIN); DQ, DM, and DQS inputs changing twice per clock cycle tREFC = tRFC (MIN) Auto refresh burst current: tREFC = 7.8µs tREFC = 1.95µs (AT) Self refresh current: CKE ≤ 0.2V Standard Low power (L) Operating bank interleave read current: Four-bank interleaving READs (burst = 4) with auto precharge; tRC = minimum tRC allowed; tCK = tCK (MIN); Address and control inputs change only during ACTIVE, READ, or WRITE commands t tRC tRC Symbol -5B 100 -6/6T 90 Units mA Notes 23, 48 IDD0 IDD1 120 115 mA 23, 48 IDD2P IDD2F 4 50 4 50 mA mA 24, 33 51 IDD3P 35 60 30 55 mA mA 24, 33 23 IDD3N IDD4R 180 160 mA 23, 48 IDD4W 180 160 mA 23 IDD5 IDD5A IDD5A IDD6 IDD6A IDD7 160 6 9 4 2 290 160 6 9 4 2 270 mA mA mA mA mA mA 50 28, 50 28, 50 12 12 23, 49 PDF: 09005aef80768abb/Source: 09005aef82a95a3a 256Mb_DDR_x4x8x16_D2.fm - 256Mb DDR: Rev. O, Core DDR: Rev. B 1/09 EN 19 Micron Technology, Inc., reserves the right to change products or specifications without notice. ©2003 Micron Technology, Inc. All rights reserved. 256Mb: x4, x8, x16 DDR SDRAM Electrical Specifications – DC and AC Electrical Specifications – DC and AC Stresses greater than those listed in Table 9 may cause permanent damage to the device. This is a stress rating only, and functional operation of the device at these or any other conditions above those indicated in the operational sections of this specification is not implied. Exposure to absolute maximum rating conditions for extended periods may affect reliability. Table 9: Parameter VDD supply voltage relative to VSS VDDQ supply voltage relative to VSS VREF and inputs voltage relative to VSS I/O pins voltage relative to VSS Storage temperature (plastic) Short circuit output current Absolute Maximum Ratings Min –1V –1V –1V –0.5V –55 – Max +3.6V +3.6V +3.6V VDDQ + 0.5V +150 50 Units V V V V °C mA Table 10: DC Electrical Characteristics and Operating Conditions (-5B) Notes: 1–5 and 17 apply to the entire table; Notes appear on page 35; VDDQ = +2.6V ±0.1V, VDD = +2.6V ±0.1V Symbol VDD VDDQ VREF VTT VIH(DC) VIL(DC) II Min +2.5 +2.5 0.49 × VDDQ VREF - 0.04 VREF + 0.15 –0.3 –2 Max +2.7 +2.7 0.51 × VDDQ VREF + 0.04 VDD + 0.3 VREF - 0.15 +2 Units V V V V V V µA Notes 37, 42 37, 42, 45 7, 45 8, 45 29 29 Parameter/Condition Supply voltage I/O supply voltage I/O reference voltage I/O termination voltage (system) Input high (logic 1) voltage Input low (logic 0) voltage Input leakage current: Any input 0V ≤ VIN ≤ VDD, VREF pin 0V ≤ VIN ≤ 1.35V (All other pins not under test = 0V) Output leakage current: (DQ are disabled; 0V ≤ VOUT ≤ VDDQ) Full-drive option output High current (VOUT = levels (x4, x8, x16): VDDQ - 0.373V, minimum IOZ IOH –5 –16.8 +5 – µA mA 38, 40 Reduced-drive option output levels (Design Revision F and K only): VREF, minimum VTT) Low current (VOUT = 0.373V, maximum VREF, maximum VTT) High current (VOUT = VDDQ - 0.373V, minimum VREF, minimum VTT) Low current (VOUT = 0.763V, maximum VREF, maximum VTT) Commercial Industrial Automotive IOL +16.8 – mA IOHR –9 – mA 39, 40 IOLR +9 – mA Ambient operating temperatures TA TA TA 0 –40 –40 +70 +85 +105 °C °C °C PDF: 09005aef80768abb/Source: 09005aef82a95a3a DDR_x4x8x16_Core2.fm - 256Mb DDR: Rev. O, Core DDR: Rev. B 1/09 EN 18 Micron Technology, Inc., reserves the right to change products or specifications without notice. ©2003 Micron Technology, Inc. All rights reserved. 256Mb: x4, x8, x16 DDR SDRAM Electrical Specifications – DC and AC Table 11: DC Electrical Characteristics and Operating Conditions (-6, -6T, -75E, -75Z, -75) Notes: 1–5, 17 apply to the entire table; Notes appear on page 35; VDDQ = +2.5V ±0.2V, VDD = +2.5V ±0.2V Parameter/Condition Supply voltage I/O supply voltage I/O reference voltage I/O termination voltage (system) Input high (logic 1) voltage Input low (logic 0) voltage Input leakage current: Any input 0V ≤ VIN ≤ VDD, VREF pin 0V ≤ VIN ≤ 1.35V (All other pins not under test = 0V) Output leakage current: (DQ are disabled; 0V ≤ VOUT ≤ VDDQ) Full-drive option output High current (VOUT = levels (x4, x8, x16): VDDQ - 0.373V, minimum Symbol VDD VDDQ VREF VTT VIH(DC) VIL(DC) II Min +2.3 +2.3 0.49 × VDDQ VREF - 0.04 VREF + 0.15 –0.3 –2 Max +2.7 +2.7 0.51 × VDDQ VREF + 0.04 VDD + 0.3 VREF - 0.15 +2 Units V V V V V V µA Notes 37, 42 37, 42, 45 7, 45 8, 45 29 29 IOZ IOH –5 –16.8 +5 – µA mA 38, 40 Reduced-drive option output levels (Design Revision F and K only): VREF, minimum VTT) Low current (VOUT = 0.373V, maximum VREF, maximum VTT) High current (VOUT = VDDQ - 0.763V, minimum VREF, minimum VTT) Low current (VOUT = 0.763V, maximum VREF, maximum VTT) Commercial Industrial Automotive IOL +16.8 – mA IOHR –9 – mA 39, 40 IOLR +9 – mA Ambient operating temperatures TA TA TA 0 –40 –40 +70 +85 +105 °C °C °C Table 12: AC Input Operating Conditions Notes: 1–5, 17 apply to the entire table; Notes appear on page 35; 0°C ≤ TA ≤ +70°C; VDDQ = +2.5V ±0.2V, VDD = +2.5V ±0.2V (VDDQ = +2.6V ±0.1V, VDD = +2.6V ±0.1V for -5B) Parameter/Condition Input high (logic 1) voltage Input low (logic 0) voltage I/O reference voltage Symbol VIH(AC) VIL(AC) VREF(AC) Min VREF + 0.310 – 0.49 × VDDQ Max – VREF - 0.310 0.51 × VDDQ Units V V V Notes 15, 29, 41 15, 29, 41 7 PDF: 09005aef80768abb/Source: 09005aef82a95a3a DDR_x4x8x16_Core2.fm - 256Mb DDR: Rev. O, Core DDR: Rev. B 1/09 EN 19 Micron Technology, Inc., reserves the right to change products or specifications without notice. ©2003 Micron Technology, Inc. All rights reserved. 256Mb: x4, x8, x16 DDR SDRAM Electrical Specifications – DC and AC Figure 10: Input Voltage Waveform VDDQ (2.3V MIN) VOH (MIN) (1.670V1 for SSTL_2 termination) System noise margin (power/ground, crosstalk, signal integrity attenuation) 1.560V VIH(AC) 1.400V VIH(DC) 1.300V 1.275V 1.250V 1.225V 1.200V VREF + AC noise VREF + DC error VREF - DC error VREF - AC noise 1.100V VIL(DC) 0.940V VIN(AC) - provides margin between VOL (MAX) and VIL(AC) VOL (MAX) (0.83V2 for SSTL_2 termination) VIL(AC) Receiver Transmitter VssQ Notes: 1. VOH (MIN) with test load is 1.927V. 2. VOL (MAX) with test load is 0.373V. 3. Numbers in diagram reflect nominal values utilizing circuit below for all devices other than -5B. VTT 25Ω 25Ω Reference point PDF: 09005aef80768abb/Source: 09005aef82a95a3a DDR_x4x8x16_Core2.fm - 256Mb DDR: Rev. O, Core DDR: Rev. B 1/09 EN 20 Micron Technology, Inc., reserves the right to change products or specifications without notice. ©2003 Micron Technology, Inc. All rights reserved. 256Mb: x4, x8, x16 DDR SDRAM Electrical Specifications – DC and AC Table 13: Clock Input Operating Conditions Notes: 1–5, 16, 17, 31 apply to the entire table; Notes appear on page 35; 0°C ≤ TA ≤ +70°C; VDDQ = +2.5V ±0.2V, VDD = +2.5V ±0.2V (VDDQ = +2.6V ±0.1V, VDD = +2.6V ±0.1V for -5B) Parameter/Condition Clock input mid-point voltage: CK and CK# Clock input voltage level: CK and CK# Clock input differential voltage: CK and CK# Clock input differential voltage: CK and CK# Clock input crossing point voltage: CK and CK# Symbol VMP(DC) VIN(DC) VID(DC) VID(AC) VIX(AC) Min 1.15 –0.3 0.36 0.7 0.5 × VDDQ - 0.2 Max 1.35 VDDQ + 0.3 VDDQ + 0.6 VDDQ + 0.6 0.5 × VDDQ + 0.2 Units V V V V V Notes 7, 10 7 7, 9 9 10 Figure 11: 2.80V SSTL_2 Clock Input Maximum clock level1 CK# 1.45V 1.25V 1.05V X 3 VMP(DC)2 VIX(AC) 4 VID(DC) VID(AC)5 X CK –0.30V Minimum clock level1 Notes: 1. 2. 3. 4. 5. 6. 7. CK or CK# may not be more positive than VDDQ + 0.3V or more negative than VSS - 0.3V. This provides a minimum of 1.15V to a maximum of 1.35V and is always half of VDDQ. CK and CK# must cross in this region. CK and CK# must meet at least VID(DC) MIN when static and is centered around VMP(DC). CK and CK# must have a minimum 700mV peak-to-peak swing. For AC operation, all DC clock requirements must also be satisfied. Numbers in diagram reflect nominal values for all devices other than -5B. PDF: 09005aef80768abb/Source: 09005aef82a95a3a DDR_x4x8x16_Core2.fm - 256Mb DDR: Rev. O, Core DDR: Rev. B 1/09 EN 21 Micron Technology, Inc., reserves the right to change products or specifications without notice. ©2003 Micron Technology, Inc. All rights reserved. 256Mb: x4, x8, x16 DDR SDRAM Electrical Specifications – DC and AC Table 14: Parameter Delta input/output capacitance: DQ0–DQ3 (x4), DQ0–DQ7 (x8) Delta input capacitance: Command and address Delta input capacitance: CK, CK# Input/output capacitance: DQ, DQS, DM Input capacitance: Command and address Input capacitance: CK, CK# Input capacitance: CKE Capacitance (x4, x8 TSOP) Note: 14 applies to the entire table; Notes appear on page 35 Symbol Min – – – 4.0 2.0 2.0 2.0 Max 0.50 0.50 0.25 5.0 3.0 3.0 3.0 Units pF pF pF pF pF pF pF Notes 25 30 30 DCIO DCI1 DCI2 CIO CI1 CI2 CI3 Table 15: Parameter Capacitance (x4, x8 FBGA) Note: 14 applies to the entire table; Notes appear on page 35 Symbol Min – – – 3.5 1.5 1.5 1.5 Max 0.50 0.50 0.25 4.5 2.5 2.5 2.5 Units pF pF pF pF pF pF pF Notes 25 30 30 Delta input/output capacitance: DQ, DQS, DM Delta input capacitance: Command and address Delta input capacitance: CK, CK# Input/output capacitance: DQ, DQS, DM Input capacitance: Command and address Input capacitance: CK, CK# Input capacitance: CKE DCIO DCI1 DCI2 CIO CI1 CI2 CI3 Table 16: Parameter Capacitance (x16 TSOP) Note: 14 applies to the entire table; Notes appear on page 35 Symbol Min – – – – 4.0 2.0 2.0 2.0 Max 0.50 0.50 0.50 0.25 5.0 3.0 3.0 3.0 Units pF pF pF pF pF pF pF pF Notes 25 25 30 30 Delta input/output capacitance: DQ0–DQ7, LDQS, LDM Delta input/output capacitance: DQ8–DQ15, UDQS, UDM Delta input capacitance: Command and address Delta input capacitance: CK, CK# Input/output capacitance: DQ, LDQS, UDQS, LDM, UDM Input capacitance: Command and address Input capacitance: CK, CK# Input capacitance: CKE DCIOL DCIOU DCI1 DCI2 CIO CI1 CI2 CI3 Table 17: Parameter Capacitance (x16 FBGA) Note: 14 applies to the entire table; Notes appear on page 35 Symbol Min – – – – 3.5 1.5 1.5 1.5 Max 0.50 0.50 0.50 0.25 4.5 2.5 2.5 2.5 Units pF pF pF pF pF pF pF pF Notes 25 25 30 30 Delta input/output capacitance: DQ0–DQ7, LDQS, LDM Delta input/output capacitance: DQ8–DQ15, UDQS, UDM Delta input capacitance: Command and address Delta input capacitance: CK, CK# Input/output capacitance: DQ, LDQS, UDQS, LDM, UDM Input capacitance: Command and address Input capacitance: CK, CK# Input capacitance: CKE DCIOL DCIOU DCI1 DCI2 CIO CI1 CI2 CI3 PDF: 09005aef80768abb/Source: 09005aef82a95a3a DDR_x4x8x16_Core2.fm - 256Mb DDR: Rev. O, Core DDR: Rev. B 1/09 EN 22 Micron Technology, Inc., reserves the right to change products or specifications without notice. ©2003 Micron Technology, Inc. All rights reserved. 256Mb: x4, x8, x16 DDR SDRAM Electrical Specifications – DC and AC Table 18: Electrical Characteristics and Recommended AC Operating Conditions (-5B) Notes 1–6, 16–18, 34 apply to the entire table; Notes appear on page 35; 0°C ≤ TA ≤ +70°C; VDDQ = +2.6V ±0.1V, VDD = +2.6V ±0.1V AC Characteristics Parameter Access window of DQ from CK/CK# CK high-level width Clock cycle time Symbol t -5B Min –0.70 0.45 5 6 7.5 0.45 0.40 1.75 –0.60 0.35 0.35 – 0.72 0.40 0.2 0.2 tCH,tCL – 0.60 2.2 0.60 –0.70 10 tHP -tQHS – 15 40 55 15 – – – – 70 15 0.9 0.4 10 0 0.25 0 0.4 Max +0.70 0.55 7.5 13 13 0.55 – – +0.60 – – 0.40 1.28 – – – – +0.70 – – – – – – 0.50 – 70,000 – – 70.3 17.55 7.8 1.95 – – 1.1 0.6 – – – – 0.6 Units ns tCK Notes 31 52 46, 52 46, 52 31 27, 32 32 AC tCH CL = 3 CL = 2.5 CL = 2 tCK CK low-level width DQ and DM input hold time relative to DQS DQ and DM input pulse width (for each input) Access window of DQS from CK/CK# DQS input high pulse width DQS input low pulse width DQS–DQ skew, DQS to last DQ valid, per group, per access WRITE command to first DQS latching transition DQ and DM input setup time relative to DQS DQS falling edge from CK rising – hold time DQS falling edge to CK rising – setup time Half-clock period Data-out High-Z window from CK/CK# Address and control input hold time (slew rate ≥0.5 V/ns) Address and control input pulse width (for each input) Address and control input setup time (slew rate ≥0.5 V/ns) Data-out Low-Z window from CK/CK# LOAD MODE REGISTER command cycle time DQ–DQS hold, DQS to first DQ to go non-valid, per access Data hold skew factor ACTIVE-to-READ with auto precharge command ACTIVE-to-PRECHARGE command ACTIVE-to-ACTIVE/AUTO REFRESH command period ACTIVE-to-READ or WRITE delay REFRESH-to-REFRESH command interval REFRESH-to-REFRESH command interval (Automotive) Average periodic refresh interval Average periodic refresh interval (Automotive) AUTO REFRESH command period PRECHARGE command period DQS read preamble DQS read postamble ACTIVE bank a to ACTIVE bank b command Terminating voltage delay to VDD DQS write preamble DQS write preamble setup time DQS write postamble CK (3) (2.5) t CK (2) t CL tDH tDIPW tDQSCK tDQSH tDQSL tDQSQ tDQSS tDS tDSH tDSS tHP tHZ tIH F tIPW tIS F tLZ tMRD tQH tQHS tRAP tRAS t RC t RCD tREFC tREFC AT tREFI t REFIAT t RFC tRP tRPRE tRPST t RRD tVTD tWPRE tWPRES tWPST t ns ns ns t CK ns ns ns tCK tCK ns tCK ns tCK tCK ns ns ns ns ns ns ns ns ns ns ns ns ns µs µs µs µs ns ns tCK tCK ns ns tCK ns tCK 26, 27 27, 32 35 19, 43 15 15 19, 43 26, 27 36 24 24 24 24 50 44 44 21, 22 20 PDF: 09005aef80768abb/Source: 09005aef82a95a3a DDR_x4x8x16_Core2.fm - 256Mb DDR: Rev. O, Core DDR: Rev. B 1/09 EN 23 Micron Technology, Inc., reserves the right to change products or specifications without notice. ©2003 Micron Technology, Inc. All rights reserved. 256Mb: x4, x8, x16 DDR SDRAM Electrical Specifications – DC and AC Table 18: Electrical Characteristics and Recommended AC Operating Conditions (-5B) (continued) Notes 1–6, 16–18, 34 apply to the entire table; Notes appear on page 35; 0°C ≤ TA ≤ +70°C; VDDQ = +2.6V ±0.1V, VDD = +2.6V ±0.1V AC Characteristics Parameter Write recovery time Internal WRITE-to-READ command delay Exit SELF REFRESH-to-non-READ command Exit SELF REFRESH-to-READ command Data valid output window Symbol t -5B Min Max Units ns tCK Notes WR tWTR t XSNR n/a tXSRD 15 – 2 – 70 – 200 – t QH - tDQSQ ns tCK ns 26 PDF: 09005aef80768abb/Source: 09005aef82a95a3a DDR_x4x8x16_Core2.fm - 256Mb DDR: Rev. O, Core DDR: Rev. B 1/09 EN 24 Micron Technology, Inc., reserves the right to change products or specifications without notice. ©2003 Micron Technology, Inc. All rights reserved. 256Mb: x4, x8, x16 DDR SDRAM Electrical Specifications – DC and AC Table 19: Electrical Characteristics and Recommended AC Operating Conditions (-6) Notes: 1–6, 16–18, 34 apply to the entire table; Notes appear on page 35; 0°C ≤ TA ≤ +70°C; VDDQ = +2.5V ±0.2V, VDD = +2.5V ±0.2V AC Characteristics Parameter Access window of DQ from CK/CK# CK high-level width Clock cycle time Symbol t -6 (FBGA) Min –0.70 0.45 6 7.5 0.45 0.45 1.75 –0.6 0.35 0.35 – 0.75 0.45 0.2 0.2 tCH, tCL – 0.75 0.8 2.2 0.75 0.8 –0.7 12 tHP -tQHS – 15 42 60 15 – – – – 72 15 0.9 0.4 12 0 0.25 Max +0.70 0.55 13 13 0.55 – – +0.6 – – 0.4 1.25 – – – – +0.7 – – – – – – – – 0.50 – 70,000 – – 70.3 17.55 7.8 1.95 – – 1.1 0.6 – – – Units ns tCK Notes 31 46, 52 46, 52 31 27, 32 32 AC tCH CL = 2.5 CL = 2 t CK low-level width DQ and DM input hold time relative to DQS DQ and DM input pulse width (for each input) Access window of DQS from CK/CK# DQS input high pulse width DQS input low pulse width DQS–DQ skew, DQS to last DQ valid, per group, per access WRITE command to first DQS latching transition DQ and DM input setup time relative to DQS DQS falling edge from CK rising - hold time DQS falling edge to CK rising - setup time Half-clock period Data-out High-Z window from CK/CK# Address and control input hold time (fast slew rate) Address and control input hold time (slow slew rate) Address and control input pulse width (for each input) Address and control input setup time (fast slew rate) Address and control input setup time (slow slew rate) Data-out Low-Z window from CK/CK# LOAD MODE REGISTER command cycle time DQ-DQS hold, DQS to first DQ to go non-valid, per access Data hold skew factor ACTIVE-to-READ with auto precharge command ACTIVE-to-PRECHARGE command ACTIVE-to-ACTIVE/AUTO REFRESH command period ACTIVE-to-READ or WRITE delay REFRESH-to-REFRESH command interval REFRESH-to-REFRESH command interval (Automotive) Average periodic refresh interval Average periodic refresh interval (Automotive) AUTO REFRESH command period PRECHARGE command period DQS read preamble DQS read postamble ACTIVE bank a to ACTIVE bank b command Terminating voltage delay to VSS DQS write preamble CK (2.5) tCK (2) t CL t DH tDIPW tDQSCK tDQSH tDQSL tDQSQ tDQSS tDS tDSH tDSS tHP t ns ns t CK ns ns ns tCK tCK ns tCK ns tCK tCK ns ns ns ns ns ns ns ns ns ns ns ns ns ns ns µs µs µs µs ns ns t CK tCK ns ns tCK 26, 27 27, 32 35 19, 43 15 HZ tIH F tIH S tIPW tIS tIS F S tLZ 15 19, 43 26, 27 tMRD tQH tQHS tRAP tRAS tRC t 36, 54 RCD tREFC tREFC t AT tREFI REFIAT t RFC tRP t RPRE tRPST t RRD tVTD tWPRE 24 24 24 24 50 44 44 PDF: 09005aef80768abb/Source: 09005aef82a95a3a DDR_x4x8x16_Core2.fm - 256Mb DDR: Rev. O, Core DDR: Rev. B 1/09 EN 25 Micron Technology, Inc., reserves the right to change products or specifications without notice. ©2003 Micron Technology, Inc. All rights reserved. 256Mb: x4, x8, x16 DDR SDRAM Electrical Specifications – DC and AC Table 19: Electrical Characteristics and Recommended AC Operating Conditions (-6) (continued) Notes: 1–6, 16–18, 34 apply to the entire table; Notes appear on page 35; 0°C ≤ TA ≤ +70°C; VDDQ = +2.5V ±0.2V, VDD = +2.5V ±0.2V AC Characteristics Parameter DQS write preamble setup time DQS write postamble Write recovery time Internal WRITE-to-READ command delay Exit SELF REFRESH-to-non-READ command Exit SELF REFRESH-to-READ command Data valid output window Symbol t -6 (FBGA) Min Max Units ns tCK Notes 21, 22 20 WPRES t tWPST WR tWTR t t XSNR XSRD n/a 0 – 0.4 0.6 15 – 1 – 75 – 200 – tQH - tDQSQ ns tCK t ns CK ns 26 PDF: 09005aef80768abb/Source: 09005aef82a95a3a DDR_x4x8x16_Core2.fm - 256Mb DDR: Rev. O, Core DDR: Rev. B 1/09 EN 26 Micron Technology, Inc., reserves the right to change products or specifications without notice. ©2003 Micron Technology, Inc. All rights reserved. 256Mb: x4, x8, x16 DDR SDRAM Electrical Specifications – DC and AC Table 20: Electrical Characteristics and Recommended AC Operating Conditions (-6T) Notes: 1–6, 16–18, 34 apply to the entire table; Notes appear on page 35; 0°C ≤ TA ≤ +70°C; VDDQ = +2.5V ±0.2V, VDD = +2.5V ±0.2V AC Characteristics Parameter Access window of DQ from CK/CK# CK high-level width Clock cycle time Symbol t -6T (TSOP) Min –0.70 0.45 6 7.5 0.45 0.45 1.75 –0.6 0.35 0.35 – 0.75 0.45 0.2 0.2 tCH, tCL – 0.75 0.8 2.2 0.75 0.8 –0.7 12 tHP -tQHS – 15 42 60 15 – – – – 72 15 0.9 0.4 12 0 0.25 Max +0.70 0.55 13 13 0.55 – – +0.6 – – 0.45 1.25 – – – – +0.7 – – – – – – – – 0.55 – 70,000 – – 70.3 17.55 7.8 1.95 – – 1.1 0.6 – – – Units ns tCK Notes 31 46, 52 46, 52 31 27, 32 32 AC tCH CL = 2.5 CL = 2 t CK low-level width DQ and DM input hold time relative to DQS DQ and DM input pulse width (for each input) Access window of DQS from CK/CK# DQS input high pulse width DQS input low pulse width DQS–DQ skew, DQS to last DQ valid, per group, per access WRITE command to first DQS latching transition DQ and DM input setup time relative to DQS DQS falling edge from CK rising - hold time DQS falling edge to CK rising - setup time Half-clock period Data-out High-Z window from CK/CK# Address and control input hold time (fast slew rate) Address and control input hold time (slow slew rate) Address and control input pulse width (for each input) Address and control input setup time (fast slew rate) Address and control input setup time (slow slew rate) Data-out Low-Z window from CK/CK# LOAD MODE REGISTER command cycle time DQ-DQS hold, DQS to first DQ to go non-valid, per access Data hold skew factor ACTIVE-to-READ with auto precharge command ACTIVE-to-PRECHARGE command ACTIVE-to-ACTIVE/AUTO REFRESH command period ACTIVE-to-READ or WRITE delay REFRESH-to-REFRESH command interval REFRESH-to-REFRESH command interval (Automotive) Average periodic refresh interval Average periodic refresh interval (Automotive) AUTO REFRESH command period PRECHARGE command period DQS read preamble DQS read postamble ACTIVE bank a to ACTIVE bank b command Terminating voltage delay to VSS DQS write preamble CK (2.5) tCK (2) t CL t DH tDIPW tDQSCK tDQSH tDQSL tDQSQ tDQSS tDS tDSH tDSS tHP t ns ns t CK ns ns ns tCK tCK ns tCK ns tCK tCK ns ns ns ns ns ns ns ns ns ns ns ns ns ns ns µs µs µs µs ns ns t CK tCK ns ns tCK 26, 27 27, 32 35 19, 43 15 HZ tIH F tIH S tIPW tIS tIS F S tLZ 15 19, 43 26, 27 tMRD tQH tQHS tRAP tRAS tRC t 36, 54 RCD tREFC tREFC t AT tREFI REFIAT t RFC tRP t RPRE tRPST t RRD tVTD tWPRE 24 24 24 24 50 44 44 PDF: 09005aef80768abb/Source: 09005aef82a95a3a DDR_x4x8x16_Core2.fm - 256Mb DDR: Rev. O, Core DDR: Rev. B 1/09 EN 27 Micron Technology, Inc., reserves the right to change products or specifications without notice. ©2003 Micron Technology, Inc. All rights reserved. 256Mb: x4, x8, x16 DDR SDRAM Electrical Specifications – DC and AC Table 20: Electrical Characteristics and Recommended AC Operating Conditions (-6T) (continued) Notes: 1–6, 16–18, 34 apply to the entire table; Notes appear on page 35; 0°C ≤ TA ≤ +70°C; VDDQ = +2.5V ±0.2V, VDD = +2.5V ±0.2V AC Characteristics Parameter DQS write preamble setup time DQS write postamble Write recovery time Internal WRITE-to-READ command delay Exit SELF REFRESH-to-non-READ command Exit SELF REFRESH-to-READ command Data valid output window Symbol t -6T (TSOP) Min Max Units ns tCK Notes 21, 22 20 WPRES t tWPST WR tWTR t t XSNR XSRD n/a 0 – 0.4 0.6 15 – 1 – 75 – 200 – tQH - tDQSQ ns tCK t ns CK ns 26 PDF: 09005aef80768abb/Source: 09005aef82a95a3a DDR_x4x8x16_Core2.fm - 256Mb DDR: Rev. O, Core DDR: Rev. B 1/09 EN 28 Micron Technology, Inc., reserves the right to change products or specifications without notice. ©2003 Micron Technology, Inc. All rights reserved. 256Mb: x4, x8, x16 DDR SDRAM Electrical Specifications – DC and AC Table 21: Electrical Characteristics and Recommended AC Operating Conditions (-75E) Notes: 1–6, 16–18, 34 apply to the entire table; Notes appear on page 35; 0°C ≤ TA ≤ +70°C; VDDQ = +2.5V ±0.2V, VDD = +2.5V ±0.2V AC Characteristics Parameter Access window of DQ from CK/CK# CK high-level width Clock cycle time Symbol t -75E Min –0.75 0.45 7.5 7.5 0.45 0.5 1.75 –0.75 0.35 0.35 – 0.75 0.5 0.2 0.2 tCH, tCL – 0.90 1 2.2 0.90 1 –0.75 15 tHP -tQHS – 15 40 60 15 – – – – 75 15 0.9 0.4 15 0 0.25 Max +0.75 0.55 13 13 0.55 – – +0.75 – – 0.5 1.25 – – – – +0.75 – – – – – – – – 0.75 – 120,000 – – 70.3 17.55 7.8 1.95 – – 1.1 0.6 – – – Units ns tCK Notes 31 46, 52 46, 52 31 27, 32 32 AC tCH CL = 2.5 CL = 2 t CK low-level width DQ and DM input hold time relative to DQS DQ and DM input pulse width (for each input) Access window of DQS from CK/CK# DQS input high pulse width DQS input low pulse width DQS–DQ skew, DQS to last DQ valid, per group, per access WRITE command to first DQS latching transition DQ and DM input setup time relative to DQS DQS falling edge from CK rising - hold time DQS falling edge to CK rising - setup time Half-clock period Data-out High-Z window from CK/CK# Address and control input hold time (fast slew rate) Address and control input hold time (slow slew rate) Address and control input pulse width (for each input) Address and control input setup time (fast slew rate) Address and control input setup time (slow slew rate) Data-out Low-Z window from CK/CK# LOAD MODE REGISTER command cycle time DQ-DQS hold, DQS to first DQ to go non-valid, per access Data hold skew factor ACTIVE-to-READ with auto precharge command ACTIVE-to-PRECHARGE command ACTIVE-to-ACTIVE/AUTO REFRESH command period ACTIVE-to-READ or WRITE delay REFRESH-to-REFRESH command interval REFRESH-to-REFRESH command interval (Automotive) Average periodic refresh interval Average periodic refresh interval (Automotive) AUTO REFRESH command period PRECHARGE command period DQS read preamble DQS read postamble ACTIVE bank a to ACTIVE bank b command Terminating voltage delay to VSS DQS write preamble CK (2.5) tCK (2) t CL t DH tDIPW tDQSCK tDQSH tDQSL tDQSQ tDQSS tDS tDSH tDSS tHP t ns ns t CK ns ns ns tCK tCK ns tCK ns tCK tCK ns ns ns ns ns ns ns ns ns ns ns ns ns ns ns µs µs µs µs ns ns t CK tCK ns ns tCK 26, 27 27, 32 35 19, 43 15 HZ tIH F tIH S tIPW tIS tIS F S tLZ 15 19, 43 26, 27 tMRD tQH tQHS tRAP tRAS tRC t 36, 54 RCD tREFC tREFC t AT tREFI REFIAT t RFC tRP t RPRE tRPST t RRD tVTD tWPRE 24 24 24 24 50 44 44 PDF: 09005aef80768abb/Source: 09005aef82a95a3a DDR_x4x8x16_Core2.fm - 256Mb DDR: Rev. O, Core DDR: Rev. B 1/09 EN 29 Micron Technology, Inc., reserves the right to change products or specifications without notice. ©2003 Micron Technology, Inc. All rights reserved. 256Mb: x4, x8, x16 DDR SDRAM Electrical Specifications – DC and AC Table 21: Electrical Characteristics and Recommended AC Operating Conditions (-75E) (continued) Notes: 1–6, 16–18, 34 apply to the entire table; Notes appear on page 35; 0°C ≤ TA ≤ +70°C; VDDQ = +2.5V ±0.2V, VDD = +2.5V ±0.2V AC Characteristics Parameter DQS write preamble setup time DQS write postamble Write recovery time Internal WRITE-to-READ command delay Exit SELF REFRESH-to-non-READ command Exit SELF REFRESH-to-READ command Data valid output window Symbol t -75E Min Max Units ns tCK Notes 21, 22 20 WPRES t tWPST WR tWTR t t XSNR XSRD n/a 0 – 0.4 0.6 15 – 1 – 75 – 200 – tQH - tDQSQ ns tCK t ns CK ns 26 PDF: 09005aef80768abb/Source: 09005aef82a95a3a DDR_x4x8x16_Core2.fm - 256Mb DDR: Rev. O, Core DDR: Rev. B 1/09 EN 30 Micron Technology, Inc., reserves the right to change products or specifications without notice. ©2003 Micron Technology, Inc. All rights reserved. 256Mb: x4, x8, x16 DDR SDRAM Electrical Specifications – DC and AC Table 22: Electrical Characteristics and Recommended AC Operating Conditions (-75Z) Notes: 1–6, 16–18, 34 apply to the entire table; Notes appear on page 35; 0°C ≤ TA ≤ +70°C; VDDQ = +2.5V ±0.2V, VDD = +2.5V ±0.2V AC Characteristics Parameter Access window of DQ from CK/CK# CK high-level width Clock cycle time Symbol t -75Z Min –0.75 0.45 7.5 7.5 0.45 0.5 1.75 –0.75 0.35 0.35 – 0.75 0.5 0.2 0.2 tCH,tCL – 0.90 1 2.2 0.90 1 –0.75 15 tHP -tQHS – 20 40 65 20 – – – – 75 20 0.9 0.4 15 0 0.25 0 Max +0.75 0.55 13 13 0.55 – – +0.75 – – 0.5 1.25 – – – – +0.75 – – – – – – – – 0.75 – 120,000 – – 70.3 17.55 7.8 1.95 – – 1.1 0.6 – – – – Units ns tCK Notes 31 46 46 31 27, 32 32 AC tCH CL = 2.5 CL = 2 t CK low-level width DQ and DM input hold time relative to DQS DQ and DM input pulse width (for each input) Access window of DQS from CK/CK# DQS input high pulse width DQS input low pulse width DQS–DQ skew, DQS to last DQ valid, per group, per access WRITE command-to-first DQS latching transition DQ and DM input setup time relative to DQS DQS falling edge from CK rising – hold time DQS falling edge to CK rising – setup time Half-clock period Data-out High-Z window from CK/CK# Address and control input hold time (fast slew rate) Address and control input hold time (slow slew rate) Address and control input pulse width (for each input) Address and control input setup time (fast slew rate) Address and control input setup time (slow slew rate) Data-out Low-Z window from CK/CK# LOAD MODE REGISTER command cycle time DQ–DQS hold, DQS to first DQ to go non-valid, per access Data hold skew factor ACTIVE-to-READ with auto precharge command ACTIVE-to-PRECHARGE command ACTIVE-to-ACTIVE/AUTO REFRESH command period ACTIVE-to-READ or WRITE delay REFRESH-to-REFRESH command interval REFRESH-to-REFRESH command interval (Automotive) Average periodic refresh interval Average periodic refresh interval (Automotive) AUTO REFRESH command period PRECHARGE command period DQS read preamble DQS read postamble ACTIVE bank a to ACTIVE bank b command Terminating voltage delay to VDD DQS write preamble DQS write preamble setup time CK (2.5) tCK (2) t CL t DH tDIPW tDQSCK tDQSH tDQSL tDQSQ tDQSS tDS tDSH tDSS tHP tHZ tIH F tIH S tIPW tIS F tIS S tLZ tMRD tQH tQHS tRAP t RAS t RC tRCD tREFC tREFC AT t REFI t REFIAT tRFC tRP tRPRE t RPST tRRD tVTD tWPRE tWPRES ns ns t CK ns ns ns tCK tCK ns tCK ns tCK tCK ns ns ns ns ns ns ns ns ns ns ns ns ns ns ns µs µs µs µs ns ns tCK t CK ns ns tCK ns 26, 27 27, 32 35 19, 43 15 15 19, 43 26, 27 36 24 24 24 24 50 44 44 21, 22 PDF: 09005aef80768abb/Source: 09005aef82a95a3a DDR_x4x8x16_Core2.fm - 256Mb DDR: Rev. O, Core DDR: Rev. B 1/09 EN 31 Micron Technology, Inc., reserves the right to change products or specifications without notice. ©2003 Micron Technology, Inc. All rights reserved. 256Mb: x4, x8, x16 DDR SDRAM Electrical Specifications – DC and AC Table 22: Electrical Characteristics and Recommended AC Operating Conditions (-75Z) (continued) Notes: 1–6, 16–18, 34 apply to the entire table; Notes appear on page 35; 0°C ≤ TA ≤ +70°C; VDDQ = +2.5V ±0.2V, VDD = +2.5V ±0.2V AC Characteristics Parameter DQS write postamble Write recovery time Internal WRITE-to-READ command delay Exit SELF REFRESH-to-non-READ command Exit SELF REFRESH-to-READ command Data valid output window Symbol t -75Z Min Max Units t Notes 20 WPST tWR t WTR tXSNR t XSRD n/a 0.4 0.6 15 – 1 – 75 – 200 – t t QH - DQSQ CK ns t CK ns t CK ns 26 PDF: 09005aef80768abb/Source: 09005aef82a95a3a DDR_x4x8x16_Core2.fm - 256Mb DDR: Rev. O, Core DDR: Rev. B 1/09 EN 32 Micron Technology, Inc., reserves the right to change products or specifications without notice. ©2003 Micron Technology, Inc. All rights reserved. 256Mb: x4, x8, x16 DDR SDRAM Electrical Specifications – DC and AC Table 23: Electrical Characteristics and Recommended AC Operating Conditions (-75) Notes: 1–6, 16–18, 34 apply to the entire table; Notes appear on page 35; 0°C ≤ TA ≤ +70°C; VDDQ = +2.5V ±0.2V, VDD = +2.5V ±0.2V AC Characteristics Parameter Access window of DQ from CK/CK# CK high-level width Clock cycle time Symbol t -75 Min –0.75 0.45 7.5 10 0.45 0.5 1.75 –0.75 0.35 0.35 – 0.75 0.5 0.2 0.2 tCH,tCL – 0.90 1 2.2 0.90 1 –0.75 15 tHP -tQHS – 20 40 65 20 – – – – 75 20 0.9 0.4 15 0 0.25 0 Max +0.75 0.55 13 13 0.55 – – +0.75 – – 0.5 1.25 – – – – +0.75 – – – – – – – – 0.75 – 120,000 – – 70.3 17.55 7.8 1.95 – – 1.1 0.6 – – – – Units ns tCK Notes 31 46 46 31 27, 32 32 AC tCH CL = 2.5 CL = 2 t CK low-level width DQ and DM input hold time relative to DQS DQ and DM input pulse width (for each input) Access window of DQS from CK/CK# DQS input high pulse width DQS input low pulse width DQS–DQ skew, DQS to last DQ valid, per group, per access WRITE command-to-first DQS latching transition DQ and DM input setup time relative to DQS DQS falling edge from CK rising – hold time DQS falling edge to CK rising – setup time Half-clock period Data-out High-Z window from CK/CK# Address and control input hold time (fast slew rate) Address and control input hold time (slow slew rate) Address and control input pulse width (for each input) Address and control input setup time (fast slew rate) Address and control input setup time (slow slew rate) Data-out Low-Z window from CK/CK# LOAD MODE REGISTER command cycle time DQ–DQS hold, DQS to first DQ to go non-valid, per access Data hold skew factor ACTIVE-to-READ with auto precharge command ACTIVE-to-PRECHARGE command ACTIVE-to-ACTIVE/AUTO REFRESH command period ACTIVE-to-READ or WRITE delay REFRESH-to-REFRESH command interval REFRESH-to-REFRESH command interval (Automotive) Average periodic refresh interval Average periodic refresh interval (Automotive) AUTO REFRESH command period PRECHARGE command period DQS read preamble DQS read postamble ACTIVE bank a to ACTIVE bank b command Terminating voltage delay to VDD DQS write preamble DQS write preamble setup time CK (2.5) tCK (2) t CL t DH tDIPW tDQSCK tDQSH tDQSL tDQSQ tDQSS tDS tDSH tDSS tHP tHZ tIH F tIH S tIPW tIS F tIS S tLZ tMRD tQH tQHS tRAP t RAS t RC tRCD tREFC tREFC AT t REFI t REFIAT trFC tRP tRPRE t RPST tRRD tVTD tWPRE tWPRES ns ns t CK ns ns ns tCK tCK ns tCK ns tCK tCK ns ns ns ns ns ns ns ns ns ns ns ns ns ns ns µs µs µs µs ns ns tCK tCK ns ns tCK ns 26, 27 27, 32 35 19, 43 15 15 19, 43 26, 27 36 24 24 24 24 50 44 44 21, 22 PDF: 09005aef80768abb/Source: 09005aef82a95a3a DDR_x4x8x16_Core2.fm - 256Mb DDR: Rev. O, Core DDR: Rev. B 1/09 EN 33 Micron Technology, Inc., reserves the right to change products or specifications without notice. ©2003 Micron Technology, Inc. All rights reserved. 256Mb: x4, x8, x16 DDR SDRAM Electrical Specifications – DC and AC Table 23: Electrical Characteristics and Recommended AC Operating Conditions (-75) (continued) Notes: 1–6, 16–18, 34 apply to the entire table; Notes appear on page 35; 0°C ≤ TA ≤ +70°C; VDDQ = +2.5V ±0.2V, VDD = +2.5V ±0.2V AC Characteristics Parameter DQS write postamble Write recovery time Internal WRITE-to-READ command delay Exit SELF REFRESH-to-non-READ command Exit SELF REFRESH-to-READ command Data valid output window Symbol tWPST tWR t WTR tXSNR t XSRD n/a Min -75 Max Units tCK ns t CK ns t CK ns Notes 20 0.4 0.6 15 – 1 – 75 – 200 – t t QH - DQSQ 26 Table 24: Input Slew Rate Derating Values for Addresses and Commands Note: 15 applies to the entire table; Notes appear on page 35; 0°C ≤ TA ≤ +70°C; VDDQ = +2.5V ±0.2V, VDD = +2.5V ±0.2V Speed -75Z/-75E -75Z/-75E -75Z/-75E Slew Rate 0.500 V/ns 0.400 V/ns 0.300 V/ns tIS tIH Units ns ns ns 1.00 1.05 1.10 1 1 1 Table 25: Input Slew Rate Derating Values for DQ, DQS, and DM Note: 32 applies to the entire table; Notes appear on page 35; 0°C ≤ TA ≤ +70°C; VDDQ = +2.5V ±0.2V, VDD = +2.5V ±0.2V Speed -75Z/-75E -75Z/-75E -75Z/-75E Slew Rate 0.500 V/ns 0.400 V/ns 0.300 V/ns tDS tDH Units ns ns ns 0.50 0.55 0.60 0.50 0.55 0.60 PDF: 09005aef80768abb/Source: 09005aef82a95a3a DDR_x4x8x16_Core2.fm - 256Mb DDR: Rev. O, Core DDR: Rev. B 1/09 EN 34 Micron Technology, Inc., reserves the right to change products or specifications without notice. ©2003 Micron Technology, Inc. All rights reserved. 256Mb: x4, x8, x16 DDR SDRAM Electrical Specifications – DC and AC Notes 1. All voltages referenced to VSS. 2. Tests for AC timing, IDD, and electrical AC and DC characteristics may be conducted at nominal reference/supply voltage levels, but the related specifications and the device operation are guaranteed for the full voltage range specified. 3. Outputs (except for IDD measurements) measured with equivalent load: VTT 50Ω Reference point 30pF Output (VOUT) 4. AC timing and IDD tests may use a VIL-to-VIH swing of up to 1.5V in the test environment, but input timing is still referenced to VREF (or to the crossing point for CK/CK#), and parameter specifications are guaranteed for the specified AC input levels under normal use conditions. The minimum slew rate for the input signals used to test the device is 1 V/ns in the range between VIL(AC) and VIH(AC). 5. The AC and DC input level specifications are as defined in the SSTL_2 standard (that is, the receiver will effectively switch as a result of the signal crossing the AC input level and will remain in that state as long as the signal does not ring back above [below] the DC input LOW [HIGH] level). 6. All speed grades are not offered on all densities. Refer to page 1 for availability. 7. VREF is expected to equal VDDQ/2 of the transmitting device and to track variations in the DC level of the same. Peak-to-peak noise (noncommon mode) on VREF may not exceed ±2% of the DC value. Thus, from VDDQ/2, VREF is allowed ±25mV for DC error and an additional ±25mV for AC noise. This measurement is to be taken at the nearest VREF bypass capacitor. 8. VTT is not applied directly to the device. VTT is a system supply for signal termination resistors, it is expected to be set equal to VREF, and it must track variations in the DC level of VREF. 9. VID is the magnitude of the difference between the input level on CK and the input level on CK#. 10. The value of VIX and VMP is expected to equal VDDQ/2 of the transmitting device and must track variations in the DC level of the same. 11. IDD is dependent on output loading and cycle rates. Specified values are obtained with minimum cycle times at CL = 3 for -5B; CL = 2.5, -6/-6T/-75; and CL = 2, -75E/-75Z speeds with the outputs open. 12. Enables on-chip refresh and address counters. 13. IDD specifications are tested after the device is properly initialized and is averaged at the defined cycle rate. 14. This parameter is sampled. VDD = +2.5V ±0.2V, VDDQ = +2.5V ±0.2V, VREF = VSS, f = 100 MHz, TA = 25°C, VOUT(DC) = VDDQ/2, VOUT (peak-to-peak) = 0.2V. DM input is grouped with I/O pins, reflecting the fact that they are matched in loading. 15. For slew rates less than 1 V/ns and greater than or equal to 0.5 V/ns. If the slew rate is less than 0.5 V/ns, timing must be derated: tIS has an additional 50ps per each 100 mV/ns reduction in slew rate from the 500 mV/ns. tIH has 0ps added, that is, it remains constant. If the slew rate exceeds 4.5 V/ns, functionality is uncertain. For -5B, -6, and -6T, slew rates must be greater than or equal to 0.5 V/ns. PDF: 09005aef80768abb/Source: 09005aef82a95a3a DDR_x4x8x16_Core2.fm - 256Mb DDR: Rev. O, Core DDR: Rev. B 1/09 EN 35 Micron Technology, Inc., reserves the right to change products or specifications without notice. ©2003 Micron Technology, Inc. All rights reserved. 256Mb: x4, x8, x16 DDR SDRAM Electrical Specifications – DC and AC 16. The CK/CK# input reference level (for timing referenced to CK/CK#) is the point at which CK and CK# cross; the input reference level for signals other than CK/CK# is VREF. 17. Inputs are not recognized as valid until VREF stabilizes. Once initialized, including self refresh mode, VREF must be powered within specified range. Exception: during the period before VREF stabilizes, CKE < 0.3 × VDD is recognized as LOW. 18. The output timing reference level, as measured at the timing reference point (indicated in Note 3), is VTT. 19. tHZ and tLZ transitions occur in the same access time windows as data valid transitions. These parameters are not referenced to a specific voltage level, but specify when the device output is no longer driving (High-Z) or begins driving (Low-Z). 20. The intent of the “Don’t Care” state after completion of the postamble is the DQSdriven signal should either be HIGH, LOW, or High-Z, and that any signal transition within the input switching region must follow valid input requirements. That is, if DQS transitions HIGH (above VIH[DC] MIN) then it must not transition LOW (below VIH[DC] prior to tDQSH [MIN]). 21. This is not a device limit. The device will operate with a negative value, but system performance could be degraded due to bus turnaround. 22. It is recommended that DQS be valid (HIGH or LOW) on or before the WRITE command. The case shown (DQS going from High-Z to logic LOW) applies when no WRITEs were previously in progress on the bus. If a previous WRITE was in progress, DQS could be HIGH during this time, depending on tDQSS. 23. MIN (tRC or tRFC) for IDD measurements is the smallest multiple of tCK that meets the minimum absolute value for the respective parameter. tRAS (MAX) for IDD measurements is the largest multiple of tCK that meets the maximum absolute value for tRAS. 24. The refresh period is 64ms (commerial and industrial) or 16ms (automotive). This equates to an average refresh rate of 7.8125µs (commercial and industrial) or 1.95us (automotive). However, an AUTO REFRESH command must be asserted at least once every 70.3µs(commerial and industrial) or 17.55µs (automotive); burst refreshing or posting by the DRAM controller greater than 8 REFRESH cycles is not allowed. 25. The I/O capacitance per DQS and DQ byte/group will not differ by more than this maximum amount for any given device. 26. The data valid window is derived by achieving other specifications: tHP (tCK/2), tDQSQ, and tQH (tQH = tHP - tQHS). The data valid window derates in direct proportion to the clock duty cycle and a practical data valid window can be derived. The clock is allowed a maximum duty cycle variation of 45/55, because functionality is uncertain when operating beyond a 45/55 ratio. The data valid window derating curves are provided in Figure 12 on page 37 for duty cycles ranging between 50/50 and 45/55. 27. Referenced to each output group: x4 = DQS with DQ0–DQ3; x8 = DQS with DQ0–DQ7; x16 = LDQS with DQ0–DQ7 and UDQS with DQ8–DQ15. 28. This limit is actually a nominal value and does not result in a fail value. CKE is HIGH during the REFRESH command period (tRFC [MIN]), else CKE is LOW (that is, during standby). 29. To maintain a valid level, the transitioning edge of the input must: 29a. Sustain a constant slew rate from the current AC level through to the target AC level, VIL(AC) or VIH(AC). 29b. Reach at least the target AC level. 29c. After the AC target level is reached, continue to maintain at least the target DC level, VIL(DC) or VIH(DC). PDF: 09005aef80768abb/Source: 09005aef82a95a3a DDR_x4x8x16_Core2.fm - 256Mb DDR: Rev. O, Core DDR: Rev. B 1/09 EN 36 Micron Technology, Inc., reserves the right to change products or specifications without notice. ©2003 Micron Technology, Inc. All rights reserved. 256Mb: x4, x8, x16 DDR SDRAM Electrical Specifications – DC and AC 30. The input capacitance per pin group will not differ by more than this maximum amount for any given device. 31. CK and CK# input slew rate must be ≥1 V/ns (≥2 V/ns if measured differentially). Figure 12: Derating Data Valid Window (tQH – tDQSQ) -6T @ tCK = 7.5ns -75E / -75 @ tCK = 7.5ns 2.75 2.71 3.0ns 2.68 2.64 -6 @ tCK = 6ns -6T @ tCK = 6ns 2.60 2.56 -5B @ tCK = 5ns 2.53 2.49 2.45 2.41 2.38 2.5ns 2.50 2.46 2.43 Data Valid Window 2.39 2.35 2.31 2.28 2.24 2.20 2.16 2.10 2.13 2.07 2.04 2.0ns 2.00 1.97 1.94 2.01 1.98 1.95 1.92 1.89 1.86 1.83 1.91 1.88 1.80 1.85 1.82 1.79 1.76 1.73 1.70 1.5ns 1.60 1.58 1.55 1.53 1.50 1.48 1.45 1.43 1.40 1.38 1.35 1.0ns 50/50 49/51 48/53 47/53 46/54 45/55 Clock Duty Cycle 32. DQ and DM input slew rates must not deviate from DQS by more than 10%. If the DQ/ DM/DQS slew rate is less than 0.5 V/ns, timing must be derated: 50ps must be added to tDS and tDH for each 100 mV/ns reduction in slew rate. For -5B, -6, and -6T speed grades, the slew rate must be ≥0.5 V/ns. If the slew rate exceeds 4 V/ns, functionality is uncertain. 33. VDD must not vary more than 4% if CKE is not active while any bank is active. 34. The clock is allowed up to ±150ps of jitter. Each timing parameter is allowed to vary by the same amount. 35. tHP (MIN) is the lesser of tCL (MIN) and tCH (MIN) actually applied to the device CK and CK# inputs, collectively, during bank active. 36. READs and WRITEs with auto precharge are not allowed to be issued until tRAS (MIN) can be satisfied prior to the internal PRECHARGE command being issued. 37. Any positive glitch must be less than 1/3 of the clock cycle and not more than +400mV or 2.9V (+300mV or 2.9V maximum for -5B), whichever is less. Any negative glitch must be less than 1/3 of the clock cycle and not exceed either –300mV or 2.2V (2.4V for -5B), whichever is more positive. The average cannot be below the +2.5V (2.6V for -5B) minimum. 38. Normal output drive curves: 38a. The full driver pull-down current variation from MIN to MAX process; temperature and voltage will lie within the outer bounding lines of the V-I curve of Figure 13 on page 38. 38b. The driver pull-down current variation, within nominal voltage and temperature limits, is expected, but not guaranteed, to lie within the inner bounding lines of the V-I curve of Figure 13 on page 38. PDF: 09005aef80768abb/Source: 09005aef82a95a3a DDR_x4x8x16_Core2.fm - 256Mb DDR: Rev. O, Core DDR: Rev. B 1/09 EN 37 Micron Technology, Inc., reserves the right to change products or specifications without notice. ©2003 Micron Technology, Inc. All rights reserved. 256Mb: x4, x8, x16 DDR SDRAM Electrical Specifications – DC and AC 38c. The full driver pull-up current variation from MIN to MAX process; temperature and voltage will lie within the outer bounding lines of the V-I curve of Figure 14 on page 38. 38d. The driver pull-up current variation within nominal limits of voltage and temperature is expected, but not guaranteed, to lie within the inner bounding lines of the V-I curve of Figure 14 on page 38. 38e. The full ratio variation of MAX to MIN pull-up and pull-down current should be between 0.71 and 1.4 for drain-to-source voltages from 0.1V to 1.0V at the same voltage and temperature. 38f. The full ratio variation of the nominal pull-up to pull-down current should be unity ±10% for device drain-to-source voltages from 0.1V to 1.0V. Figure 13: Full Drive Pull-Down Characteristics 160 140 120 100 IOUT (mA) 80 60 40 20 0 0.0 0.5 1.0 1.5 2.0 2.5 VOUT (V) Figure 14: Full Drive Pull-Up Characteristics 0 -20 -40 -60 IOUT (mA) -80 -100 -120 -140 -160 -180 -200 0.0 0.5 1.0 1.5 2.0 2.5 VDDQ - VOUT (V) 39. Reduced output drive curves: 39a. The full driver pull-down current variation from MIN to MAX process; temperature and voltage will lie within the outer bounding lines of the V-I curve of Figure 15 on page 39. 39b. The driver pull-down current variation, within nominal voltage and temperature limits, is expected, but not guaranteed, to lie within the inner bounding lines of the V-I curve of Figure 15 on page 39. 39c. The full driver pull-up current variation from MIN to MAX process; temperature and voltage will lie within the outer bounding lines of the V-I curve of Figure 16. PDF: 09005aef80768abb/Source: 09005aef82a95a3a DDR_x4x8x16_Core2.fm - 256Mb DDR: Rev. O, Core DDR: Rev. B 1/09 EN 38 Micron Technology, Inc., reserves the right to change products or specifications without notice. ©2003 Micron Technology, Inc. All rights reserved. 256Mb: x4, x8, x16 DDR SDRAM Electrical Specifications – DC and AC 39d. The driver pull-up current variation, within nominal voltage and temperature limits, is expected, but not guaranteed, to lie within the inner bounding lines of the V-I curve of Figure 16 on page 39. 39e. The full ratio variation of the MAX-to-MIN pull-up and pull-down current should be between 0.71 and 1.4 for device drain-to-source voltages from 0.1V to 1.0V at the same voltage and temperature. 39f. The full ratio variation of the nominal pull-up to pull-down current should be unity ±10%, for device drain-to-source voltages from 0.1V to 1.0V. Figure 15: Reduced Drive Pull-Down Characteristics 80 70 60 50 IOUT (mA) 40 30 20 10 0 0 .0 0 .5 1.0 1.5 2.0 2.5 VOUT (V) Figure 16: Reduced Drive Pull-Up Characteristics 0 -10 -20 -30 IOUT (mA) -40 -50 -60 -70 -80 0.0 0.5 1.0 1.5 2.0 2.5 VDDQ - VOUT (V) 40. The voltage levels used are derived from a minimum VDD level and the referenced test load. In practice, the voltage levels obtained from a properly terminated bus will provide significantly different voltage values. 41. VIH overshoot: VIH (MAX) = VDDQ + 1.5V for a pulse width ≤ 3ns, and the pulse width can not be greater than 1/3 of the cycle rate. VIL undershoot: VIL (MIN) = –1.5V for a pulse width ≤ 3ns, and the pulse width can not be greater than 1/3 of the cycle rate. 42. VDD and VDDQ must track each other. 43. tHZ (MAX) will prevail over tDQSCK (MAX) + tRPST (MAX) condition. tLZ (MIN) will prevail over tDQSCK (MIN) + tRPRE (MAX) condition. PDF: 09005aef80768abb/Source: 09005aef82a95a3a DDR_x4x8x16_Core2.fm - 256Mb DDR: Rev. O, Core DDR: Rev. B 1/09 EN 39 Micron Technology, Inc., reserves the right to change products or specifications without notice. ©2003 Micron Technology, Inc. All rights reserved. 256Mb: x4, x8, x16 DDR SDRAM Electrical Specifications – DC and AC 44. tRPST end point and tRPRE begin point are not referenced to a specific voltage level but specify when the device output is no longer driving (tRPST) or begins driving (tRPRE). 45. During initialization, VDDQ, VTT, and VREF must be equal to or less than VDD + 0.3V. Alternatively, VTT may be 1.35V maximum during power-up, even if VDD/VDDQ are 0V, provided a minimum of 42Ω of series resistance is used between the VTT supply and the input pin. 46. The current Micron part operates below 83 MHz (slowest specified JEDEC operating frequency). As such, future die may not reflect this option. 47. When an input signal is HIGH or LOW, it is defined as a steady state logic HIGH or LOW. 48. Random address is changing; 50% of data is changing at every transfer. 49. Random address is changing; 100% of data is changing at every transfer. 50. CKE must be active (HIGH) during the entire time a REFRESH command is executed. That is, from the time the AUTO REFRESH command is registered, CKE must be active at each rising clock edge, until tRFC has been satisfied. 51. IDD2N specifies the DQ, DQS, and DM to be driven to a valid HIGH or LOW logic level. IDD2Q is similar to IDD2F except IDD2Q specifies the address and control inputs to remain stable. Although IDD2F, IDD2N, and IDD2Q are similar, IDD2F is “worst case.” 52. Whenever the operating frequency is altered, not including jitter, the DLL is required to be reset followed by 200 clock cycles before any READ command. 53. This is the DC voltage supplied at the DRAM and is inclusive of all noise up to 20 MHz. Any noise above 20 MHz at the DRAM generated from any source other than that of the DRAM itself may not exceed the DC voltage range of 2.6V ±100mV. 54. The -6/-6T speed grades will operate with tRAS (MIN) = 40ns and t RAS (MAX) = 120,000ns at any slower frequency. PDF: 09005aef80768abb/Source: 09005aef82a95a3a DDR_x4x8x16_Core2.fm - 256Mb DDR: Rev. O, Core DDR: Rev. B 1/09 EN 40 Micron Technology, Inc., reserves the right to change products or specifications without notice. ©2003 Micron Technology, Inc. All rights reserved. 256Mb: x4, x8, x16 DDR SDRAM Electrical Specifications – DC and AC Table 26: Normal Output Drive Characteristics Characteristics are specified under best, worst, and nominal process variation/conditions Pull-Down Current (mA) Voltage (V) 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.0 1.1 1.2 1.3 1.4 1.5 1.6 1.7 1.8 1.9 2.0 2.1 2.2 2.3 2.4 2.5 2.6 2.7 Nominal Low 6.0 12.2 18.1 24.1 29.8 34.6 39.4 43.7 47.5 51.3 54.1 56.2 57.9 59.3 60.1 60.5 61.0 61.5 62.0 62.5 62.8 63.3 63.8 64.1 64.6 64.8 65.0 Nominal High 6.8 13.5 20.1 26.6 33.0 39.1 44.2 49.8 55.2 60.3 65.2 69.9 74.2 78.4 82.3 85.9 89.1 92.2 95.3 97.2 99.1 100.9 101.9 102.8 103.8 104.6 105.4 Min 4.6 9.2 13.8 18.4 23.0 27.7 32.2 36.8 39.6 42.6 44.8 46.2 47.1 47.4 47.7 48.0 48.4 48.9 49.1 49.4 49.6 49.8 49.9 50.0 50.2 50.4 50.5 Max 9.6 18.2 26.0 33.9 41.8 49.4 56.8 63.2 69.9 76.3 82.5 88.3 93.8 99.1 103.8 108.4 112.1 115.9 119.6 123.3 126.5 129.5 132.4 135.0 137.3 139.2 140.8 Nominal Low –6.1 –12.2 –18.1 –24.0 –29.8 –34.3 –38.1 –41.1 –43.8 –46.0 –47.8 –49.2 –50.0 –50.5 –50.7 –51.0 –51.1 –51.3 –51.5 –51.6 –51.8 –52.0 –52.2 –52.3 –52.5 –52.7 –52.8 Pull-Up Current (mA) Nominal High –7.6 –14.5 –21.2 –27.7 –34.1 –40.5 –46.9 –53.1 –59.4 –65.5 –71.6 –77.6 –83.6 –89.7 –95.5 –101.3 –107.1 –112.4 –118.7 –124.0 –129.3 –134.6 –139.9 –145.2 –150.5 –155.3 –160.1 Min –4.6 –9.2 –13.8 –18.4 –23.0 –27.7 –32.2 –36.0 –38.2 –38.7 –39.0 –39.2 –39.4 –39.6 –39.9 –40.1 –40.2 –40.3 –40.4 –40.5 –40.6 –40.7 –40.8 –40.9 –41.0 –41.1 –41.2 Max –10.0 –20.0 –29.8 –38.8 –46.8 –54.4 –61.8 –69.5 –77.3 –85.2 –93.0 –100.6 –108.1 –115.5 –123.0 –130.4 –136.7 –144.2 –150.5 –156.9 –163.2 –169.6 –176.0 –181.3 –187.6 –192.9 –198.2 PDF: 09005aef80768abb/Source: 09005aef82a95a3a DDR_x4x8x16_Core2.fm - 256Mb DDR: Rev. O, Core DDR: Rev. B 1/09 EN 41 Micron Technology, Inc., reserves the right to change products or specifications without notice. ©2003 Micron Technology, Inc. All rights reserved. 256Mb: x4, x8, x16 DDR SDRAM Electrical Specifications – DC and AC Table 27: Reduced Output Drive Characteristics Characteristics are specified under best, worst, and nominal process variation/conditions Pull-Down Current (mA) Voltage (V) 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.0 1.1 1.2 1.3 1.4 1.5 1.6 1.7 1.8 1.9 2.0 2.1 2.2 2.3 2.4 2.5 2.6 2.7 Nominal Low 3.4 6.9 10.3 13.6 16.9 19.9 22.3 24.7 26.9 29.0 30.6 31.8 32.8 33.5 34.0 34.3 34.5 34.8 35.1 35.4 35.6 35.8 36.1 36.3 36.5 36.7 36.8 Nominal High 3.8 7.6 11.4 15.1 18.7 22.1 25.0 28.2 31.3 34.1 36.9 39.5 42.0 44.4 46.6 48.6 50.5 52.2 53.9 55.0 56.1 57.1 57.7 58.2 58.7 59.2 59.6 Min 2.6 5.2 7.8 10.4 13.0 15.7 18.2 20.8 22.4 24.1 25.4 26.2 26.6 26.8 27.0 27.2 27.4 27.7 27.8 28.0 28.1 28.2 28.3 28.3 28.4 28.5 28.6 Max 5.0 9.9 14.6 19.2 23.6 28.0 32.2 35.8 39.5 43.2 46.7 50.0 53.1 56.1 58.7 61.4 63.5 65.6 67.7 69.8 71.6 73.3 74.9 76.4 77.7 78.8 79.7 Nominal Low –3.5 –6.9 –10.3 –13.6 –16.9 –19.4 –21.5 –23.3 –24.8 –26.0 –27.1 –27.8 –28.3 –28.6 –28.7 –28.9 –28.9 –29.0 –29.2 –29.2 –29.3 –29.5 –29.5 –29.6 –29.7 –29.8 –29.9 Pull-Up Current (mA) Nominal High –4.3 –7.8 –12.0 –15.7 –19.3 –22.9 –26.5 –30.1 –33.6 –37.1 –40.3 –43.1 –45.8 –48.4 –50.7 –52.9 –55.0 –56.8 –58.7 –60.0 –61.2 –62.4 –63.1 –63.8 –64.4 –65.1 –65.8 Min –2.6 –5.2 –7.8 –10.4 –13.0 –15.7 –18.2 –20.4 –21.6 –21.9 –22.1 –22.2 –22.3 –22.4 –22.6 –22.7 –22.7 –22.8 –22.9 –22.9 –23.0 –23.0 –23.1 –23.2 –23.2 –23.3 –23.3 Max –5.0 –9.9 –14.6 –19.2 –23.6 –28.0 –32.2 –35.8 –39.5 –43.2 –46.7 –50.0 –53.1 –56.1 –58.7 –61.4 –63.5 –65.6 –67.7 –69.8 –71.6 –73.3 –74.9 –76.4 –77.7 –78.8 –79.7 PDF: 09005aef80768abb/Source: 09005aef82a95a3a DDR_x4x8x16_Core2.fm - 256Mb DDR: Rev. O, Core DDR: Rev. B 1/09 EN 42 Micron Technology, Inc., reserves the right to change products or specifications without notice. ©2003 Micron Technology, Inc. All rights reserved. 256Mb: x4, x8, x16 DDR SDRAM Commands Commands Tables 28 and 29 provide a quick reference of available commands. Two additional Truth Tables—Table 30 on page 44 and Table 31 on page 45—provide current state/next state information. Table 28: Truth Table 1 – Commands CKE is HIGH for all commands shown except SELF REFRESH; All states and sequences not shown are illegal or reserved Function DESELECT NO OPERATION (NOP) ACTIVE (select bank and activate row) READ (select bank and column and start READ burst) WRITE (select bank and column and start WRITE burst) BURST TERMINATE PRECHARGE (deactivate row in bank or banks) AUTO REFRESH or SELF REFRESH (enter self refresh mode) LOAD MODE REGISTER Notes: CS# H L L L L L L L L RAS# X H L H H H L L L CAS# X H H L L H H L L WE# X H H H L L L H L Address X X Bank/row Bank/col Bank/col X Code X Op-code Notes 1 1 2 3 3 4 5 6, 7 8 1. DESELECT and NOP are functionally interchangeable. 2. BA0–BA1 provide bank address and A0–An (128Mb: n = 11; 256Mb and 512Mb: n = 12; 1Gb: n = 13) provide row address. 3. BA0–BA1 provide bank address; A0–Ai provide column address, (where Ai is the most significant column address bit for a given density and configuration, see Table 2 on page 2) A10 HIGH enables the auto precharge feature (non persistent), and A10 LOW disables the auto precharge feature. 4. Applies only to READ bursts with auto precharge disabled; this command is undefined (and should not be used) for READ bursts with auto precharge enabled and for WRITE bursts. 5. A10 LOW: BA0–BA1 determine which bank is precharged. A10 HIGH: all banks are precharged and BA0–BA1 are “Don’t Care.” 6. This command is AUTO REFRESH if CKE is HIGH; SELF REFRESH if CKE is LOW. 7. Internal refresh counter controls row addressing while in self refresh mode, all inputs and I/Os are “Don’t Care” except for CKE. 8. BA0–BA1 select either the mode register or the extended mode register (BA0 = 0, BA1 = 0 select the mode register; BA0 = 1, BA1 = 0 select extended mode register; other combinations of BA0–BA1 are reserved). A0–An provide the op-code to be written to the selected mode register. Table 29: Truth Table 2 – DM Operation Used to mask write data, provided coincident with the corresponding data Name (Function) Write enable Write inhibit DM L H DQ Valid X PDF: 09005aef80768abb/Source: 09005aef82a95a3a DDR_x4x8x16_Core2.fm - 256Mb DDR: Rev. O, Core DDR: Rev. B 1/09 EN 43 Micron Technology, Inc., reserves the right to change products or specifications without notice. ©2003 Micron Technology, Inc. All rights reserved. 256Mb: x4, x8, x16 DDR SDRAM Commands Table 30: Truth Table 3 – Current State Bank n – Command to Bank n Notes: 1–6 apply to the entire table; Notes appear below Current State Any Idle CS# H L L L L L L L L L L L L L L Notes: RAS# X H L L L H H L H H L H H H L CAS# X H H L L L L H L L H H L L H WE# X H H H L H L L H L L L H L L Command/Action DESELECT (NOP/continue previous operation) NO OPERATION (NOP/continue previous operation) ACTIVE (select and activate row) AUTO REFRESH LOAD MODE REGISTER READ (select column and start READ burst) WRITE (select column and start WRITE burst) PRECHARGE (deactivate row in bank or banks) READ (select column and start new READ burst) WRITE (select column and start WRITE burst) PRECHARGE (truncate READ burst, start PRECHARGE) BURST TERMINATE READ (select column and start READ burst) WRITE (select column and start new WRITE burst) PRECHARGE (truncate WRITE burst, start PRECHARGE) Notes Row active Read (auto precharge disabled) Write (auto precharge disabled) 7 7 10 10 8 10 10, 12 8 9 10, 11 10 8, 11 1. This table applies when CKEn-1 was HIGH and CKEn is HIGH (see Table 33 on page 47) and after tXSNR has been met (if the previous state was self refresh). 2. This table is bank-specific, except where noted (that is, the current state is for a specific bank and the commands shown are those allowed to be issued to that bank when in that state). Exceptions are covered in the notes below. 3. Current state definitions: • Idle: The bank has been precharged, and tRP has been met. • Row active: A row in the bank has been activated, and tRCD has been met. No data bursts/accesses and no register accesses are in progress. • Read: A READ burst has been initiated, with auto precharge disabled, and has not yet terminated or been terminated. • Write: A WRITE burst has been initiated, with auto precharge disabled, and has not yet terminated or been terminated. 4. The following states must not be interrupted by a command issued to the same bank. COMMAND INHIBIT or NOP commands, or allowable commands to the other bank should be issued on any clock edge occurring during these states. Allowable commands to the other bank are determined by its current state and Table 30 and according to Table 31 on page 45. • Precharging: Starts with registration of a PRECHARGE command and ends when tRP is met. Once tRP is met, the bank will be in the idle state. • Row activating: Starts with registration of an ACTIVE command and ends when tRCD is met. Once tRCD is met, the bank will be in the “row active” state. • Read with auto precharge enabled: Starts with registration of a READ command with auto precharge enabled and ends when tRP has been met. Once tRP is met, the bank will be in the idle state. • Write with auto precharge enabled: Starts with registration of a WRITE command with auto precharge enabled and ends when tRP has been met. Once tRP is met, the bank will be in the idle state. 5. The following states must not be interrupted by any executable command; COMMAND INHIBIT or NOP commands must be applied on each positive clock edge during these states. PDF: 09005aef80768abb/Source: 09005aef82a95a3a DDR_x4x8x16_Core2.fm - 256Mb DDR: Rev. O, Core DDR: Rev. B 1/09 EN 44 Micron Technology, Inc., reserves the right to change products or specifications without notice. ©2003 Micron Technology, Inc. All rights reserved. 256Mb: x4, x8, x16 DDR SDRAM Commands • Refreshing: Starts with registration of an AUTO REFRESH command and ends when tRFC is met. Once tRFC is met, the DDR SDRAM will be in the all banks idle state. • Accessing mode register: Starts with registration of an LMR command and ends when t MRD has been met. Once tMRD is met, the DDR SDRAM will be in the all banks idle state. • Precharging all: Starts with registration of a PRECHARGE ALL command and ends when t RP is met. Once tRP is met, all banks will be in the idle state. All states and sequences not shown are illegal or reserved. Not bank-specific; requires that all banks are idle, and bursts are not in progress. May or may not be bank-specific; if multiple banks are to be precharged, each must be in a valid state for precharging. Not bank-specific; BURST TERMINATE affects the most recent READ burst, regardless of bank. READs or WRITEs listed in the Command/Action column include READs or WRITEs with auto precharge enabled and READs or WRITEs with auto precharge disabled. Requires appropriate DM masking. A WRITE command may be applied after the completion of the READ burst; otherwise, a BURST TERMINATE must be used to end the READ burst prior to asserting a WRITE command. 6. 7. 8. 9. 10. 11. 12. Table 31: Truth Table 4 – Current State Bank n – Command to Bank m Notes: 1–6 apply to the entire table; Notes appear on page 45 CS# H L X L L L L L L L L L L L L L L L L L L L L RAS# X H X L H H L L H H L L H H L L H H L L H H L CAS# X H X H L L H H L L H H L L H H L L H H L L H WE# X H X H H L L H H L L H H L L H H L L H H L L Command/Action DESELECT (NOP/continue previous operation) NO OPERATION (NOP/continue previous operation) Any command otherwise allowed to bank m ACTIVE (select and activate row) READ (select column and start READ burst) WRITE (select column and start WRITE burst) PRECHARGE ACTIVE (select and activate row) READ (select column and start new READ burst) WRITE (select column and start WRITE burst) PRECHARGE ACTIVE (select and activate row) READ (select column and start READ burst) WRITE (select column and start new WRITE burst) PRECHARGE ACTIVE (select and activate row) READ (select column and start new READ burst) WRITE (select column and start WRITE burst) PRECHARGE ACTIVE (select and activate row) READ (select column and start READ burst) WRITE (select column and start new WRITE burst) PRECHARGE Notes Current State Any Idle Row activating, active, or precharging 7 7 Read (auto precharge disabled) 7 7, 9 Write (auto precharge disabled) 7, 8 7 Read (with autoprecharge) 7 7, 9 Write (with autoprecharge) 7 7 Notes: 1. This table applies when CKEn-1 was HIGH and CKEn is HIGH (see Table 33 on page 47) and after tXSNR has been met (if the previous state was self refresh). PDF: 09005aef80768abb/Source: 09005aef82a95a3a DDR_x4x8x16_Core2.fm - 256Mb DDR: Rev. O, Core DDR: Rev. B 1/09 EN 45 Micron Technology, Inc., reserves the right to change products or specifications without notice. ©2003 Micron Technology, Inc. All rights reserved. 256Mb: x4, x8, x16 DDR SDRAM Commands 2. This table describes alternate bank operation, except where noted (that is, the current state is for bank n, and the commands shown are those allowed to be issued to bank m, assuming that bank m is in such a state that the given command is allowable). Exceptions are covered in the notes below. 3. Current state definitions: • Idle: The bank has been precharged, and tRP has been met. • Row active: A row in the bank has been activated, and tRCD has been met. No data bursts/accesses and no register accesses are in progress. • Read: A READ burst has been initiated, with auto precharge disabled, and has not yet terminated or been terminated. • Write: A WRITE burst has been initiated, with auto precharge disabled, and has not yet terminated or been terminated. • Read with auto precharge enabled: See note 3a below. • Write with auto precharge enabled: See note 3a below. a. The read with auto precharge enabled or write with auto precharge enabled states can each be broken into two parts: the access period and the precharge period. For read with auto precharge, the precharge period is defined as if the same burst was executed with auto precharge disabled and then followed with the earliest possible PRECHARGE command that still accesses all of the data in the burst. For write with auto precharge, the precharge period begins when tWR ends, with tWR measured as if auto precharge was disabled. The access period starts with registration of the command and ends where the precharge period (or tRP) begins. This device supports concurrent auto precharge such that when a read with auto precharge is enabled or a write with auto precharge is enabled, any command to other banks is allowed, as long as that command does not interrupt the read or write data transfer already in process. In either case, all other related limitations apply (for example, contention between read data and write data must be avoided). b. The minimum delay from a READ or WRITE command with auto precharge enabled, to a command to a different bank is summarized in Table 32. Table 32: From Command Command Delays CLRU = CL rounded up to the next integer To Command READ or READ with auto precharge WRITE or WRITE with auto precharge PRECHARGE ACTIVE READ or READ with auto precharge WRITE or WRITE with auto precharge PRECHARGE ACTIVE Minimum Delay with Concurrent Auto Precharge [1 + (BL/2)] × tCK + tWTR (BL/2) × tCK 1 tCK 1 tCK (BL/2) × tCK [CLRU + (BL/2)] × tCK 1 tCK 1 tCK WRITE with auto precharge READ with auto precharge 4. AUTO REFRESH and LMR commands may only be issued when all banks are idle. 5. A BURST TERMINATE command cannot be issued to another bank; it applies to the bank represented by the current state only. 6. All states and sequences not shown are illegal or reserved. 7. READs or WRITEs listed in the “Command/Action” column include READs or WRITEs with auto precharge enabled and READs or WRITEs with auto precharge disabled. 8. Requires appropriate DM masking. 9. A WRITE command may be applied after the completion of the READ burst; otherwise, a BURST TERMINATE must be used to end the READ burst prior to asserting a WRITE command. PDF: 09005aef80768abb/Source: 09005aef82a95a3a DDR_x4x8x16_Core2.fm - 256Mb DDR: Rev. O, Core DDR: Rev. B 1/09 EN Micron Technology, Inc., reserves the right to change products or specifications without notice. ©2003 Micron Technology, Inc. All rights reserved. 46 256Mb: x4, x8, x16 DDR SDRAM Commands Table 33: CKEn-1 L L H Truth Table 5 – CKE Notes 1–6 apply to the entire table; Notes appear below CKEn L H L Current State Power-down Self refresh Power-down Self refresh All banks idle Bank(s) active All banks idle Notes: Commandn X X DESELECT or NOP DESELECT or NOP DESELECT or NOP DESELECT or NOP AUTO REFRESH See Table 28 on page 43 Actionn Maintain power-down Maintain self refresh Exit power-down Exit self refresh Precharge power-down entry Active power-down entry Self refresh entry Notes 7 H H 1. CKEn is the logic state of CKE at clock edge n; CKEn-1 was the state of CKE at the previous clock edge. 2. Current state is the state of the DDR SDRAM immediately prior to clock edge n. 3. COMMANDn is the command registered at clock edge n, and ACTIONn is a result of COMMANDn. 4. All states and sequences not shown are illegal or reserved. 5. CKE must not drop LOW during a column access. For a READ, this means CKE must stay HIGH until after the read postamble time (tRPST); for a WRITE, CKE must stay HIGH until the write recovery time (tWR) has been met. 6. Once initialized, including during self refresh mode, VREF must be powered within the specified range. 7. Upon exit of the self refresh mode, the DLL is automatically enabled. A minimum of 200 clock cycles is needed before applying a READ command for the DLL to lock. DESELECT or NOP commands should be issued on any clock edges occurring during the tXSNR period. DESELECT The DESELECT function (CS# HIGH) prevents new commands from being executed by the DDR SDRAM. The DDR SDRAM is effectively deselected. Operations already in progress are not affected. NO OPERATION (NOP) The NO OPERATION (NOP) command is used to instruct the selected DDR SDRAM to perform a NOP (CS# is LOW with RAS#, CAS#, and WE# are HIGH). This prevents unwanted commands from being registered during idle or wait states. Operations already in progress are not affected. LOAD MODE REGISTER (LMR) The mode registers are loaded via inputs A0–An (see "REGISTER DEFINITION" on page 55). The LMR command can only be issued when all banks are idle, and a subsequent executable command cannot be issued until tMRD is met. PDF: 09005aef80768abb/Source: 09005aef82a95a3a DDR_x4x8x16_Core2.fm - 256Mb DDR: Rev. O, Core DDR: Rev. B 1/09 EN 47 Micron Technology, Inc., reserves the right to change products or specifications without notice. ©2003 Micron Technology, Inc. All rights reserved. 256Mb: x4, x8, x16 DDR SDRAM Commands ACTIVE (ACT) The ACTIVE command is used to open (or activate) a row in a particular bank for a subsequent access, like a read or a write, as shown in Figure 17. The value on the BA0, BA1 inputs selects the bank, and the address provided on inputs A0–An selects the row. Figure 17: Activating a Specific Row in a Specific Bank CK# CK CKE CS# HIGH RAS# CAS# WE# Address Row BA0, BA1 Bank Don’t Care PDF: 09005aef80768abb/Source: 09005aef82a95a3a DDR_x4x8x16_Core2.fm - 256Mb DDR: Rev. O, Core DDR: Rev. B 1/09 EN 48 Micron Technology, Inc., reserves the right to change products or specifications without notice. ©2003 Micron Technology, Inc. All rights reserved. 256Mb: x4, x8, x16 DDR SDRAM Commands READ The READ command is used to initiate a burst read access to an active row, as shown in Figure 18 on page 49. The value on the BA0, BA1 inputs selects the bank, and the address provided on inputs A0–Ai (where Ai is the most significant column address bit for a given density and configuration, see Table 2 on page 2) selects the starting column location. Figure 18: READ Command CK# CK CKE CS# HIGH RAS# CAS# WE# Address Col EN AP A10 DIS AP BA0, BA1 Bank Don’t Care Note: EN AP = enable auto precharge; DIS AP = disable auto precharge. PDF: 09005aef80768abb/Source: 09005aef82a95a3a DDR_x4x8x16_Core2.fm - 256Mb DDR: Rev. O, Core DDR: Rev. B 1/09 EN 49 Micron Technology, Inc., reserves the right to change products or specifications without notice. ©2003 Micron Technology, Inc. All rights reserved. 256Mb: x4, x8, x16 DDR SDRAM Commands WRITE The WRITE command is used to initiate a burst write access to an active row as shown in Figure 19. The value on the BA0, BA1 inputs selects the bank, and the address provided on inputs A0–Ai (where Ai is the most significant column address bit for a given density and configuration, see Table 2 on page 2) selects the starting column location. Figure 19: WRITE Command CK# CK CKE HIGH CS# RAS# CAS# WE# Address Col EN AP A10 DIS AP BA0, BA1 Bank Don’t Care Note: EN AP = enable auto precharge; and DIS AP = disable auto precharge. PDF: 09005aef80768abb/Source: 09005aef82a95a3a DDR_x4x8x16_Core2.fm - 256Mb DDR: Rev. O, Core DDR: Rev. B 1/09 EN 50 Micron Technology, Inc., reserves the right to change products or specifications without notice. ©2003 Micron Technology, Inc. All rights reserved. 256Mb: x4, x8, x16 DDR SDRAM Commands PRECHARGE (PRE) The PRECHARGE command is used to deactivate the open row in a particular bank or the open row in all banks as shown in Figure 20. The value on the BA0, BA1 inputs selects the bank, and the A10 input selects whether a single bank is precharged or whether all banks are precharged. Figure 20: PRECHARGE Command CK# CK CKE CS# HIGH RAS# CAS# WE# Address All banks A10 One bank BA0, BA1 Bank1 Don’t Care Notes: 1. If A10 is HIGH, bank address becomes “Don’t Care.” BURST TERMINATE (BST) The BURST TERMINATE command is used to truncate READ bursts (with auto precharge disabled). The most recently registered READ command prior to the BURST TERMINATE command will be truncated, as shown in “Operations” on page 52. The open page from which the READ burst was terminated remains open. AUTO REFRESH (AR) AUTO REFRESH is used during normal operation of the DDR SDRAM and is analogous to CAS#-before-RAS# (CBR) refresh in FPM/EDO DRAMs. This command is nonpersistent, so it must be issued each time a refresh is required. All banks must be idle before an AUTO REFRESH command is issued. SELF REFRESH The SELF REFRESH command can be used to retain data in the DDR SDRAM, even if the rest of the system is powered down. The SELF REFRESH command is initiated like an AUTO REFRESH command except CKE is disabled (LOW). Self refresh is not supported on automotive temperature (AT) devices. PDF: 09005aef80768abb/Source: 09005aef82a95a3a DDR_x4x8x16_Core2.fm - 256Mb DDR: Rev. O, Core DDR: Rev. B 1/09 EN 51 Micron Technology, Inc., reserves the right to change products or specifications without notice. ©2003 Micron Technology, Inc. All rights reserved. 256Mb: x4, x8, x16 DDR SDRAM Operations Operations INITIALIZATION Prior to normal operation, DDR SDRAMs must be powered up and initialized in a predefined manner. Operational procedures, other than those specified, may result in undefined operation. To ensure device operation, the DRAM must be initialized as described in the following steps: 1. Simultaneously apply power to VDD and VDDQ. 2. Apply VREF and then VTT power. VTT must be applied after VDDQ to avoid device latchup, which may cause permanent damage to the device. Except for CKE, inputs are not recognized as valid until after VREF is applied. 3. Assert and hold CKE at a LVCMOS logic LOW. Maintaining an LVCMOS LOW level on CKE during power-up is required to ensure that the DQ and DQS outputs will be in the High-Z state, where they will remain until driven in normal operation (by a read access). 4. Provide stable clock signals. 5. Wait at least 200µs. 6. Bring CKE HIGH, and provide at least one NOP or DESELECT command. At this point, the CKE input changes from a LVCMOS input to a SSTL_2 input only and will remain a SSTL_2 input unless a power cycle occurs. 7. Perform a PRECHARGE ALL command. 8. Wait at least tRP time; during this time NOPs or DESELECT commands must be given. 9. Using the LMR command, program the extended mode register (E0 = 0 to enable the DLL and E1 = 0 for normal drive; or E1 = 1 for reduced drive and E2–En must be set to 0 [where n = most significant bit]). 10. Wait at least tMRD time; only NOPs or DESELECT commands are allowed. 11. Using the LMR command, program the mode register to set operating parameters and to reset the DLL. At least 200 clock cycles are required between a DLL reset and any READ command. 12. Wait at least tMRD time; only NOPs or DESELECT commands are allowed. 13. Issue a PRECHARGE ALL command. 14. Wait at least tRP time; only NOPs or DESELECT commands are allowed. 15. Issue an AUTO REFRESH command. This may be moved prior to step 13. 16. Wait at least tRFC time; only NOPs or DESELECT commands are allowed. 17. Issue an AUTO REFRESH command. This may be moved prior to step 13. 18. Wait at least tRFC time; only NOPs or DESELECT commands are allowed. 19. Although not required by the Micron device, JEDEC requires an LMR command to clear the DLL bit (set M8 = 0). If an LMR command is issued, the same operating parameters should be utilized as in step 11. 20. Wait at least tMRD time; only NOPs or DESELECT commands are supported. 21. At this point the DRAM is ready for any valid command. At least 200 clock cycles with CKE HIGH are required between step 11 (DLL RESET) and any READ command. PDF: 09005aef80768abb/Source: 09005aef82a95a3a DDR_x4x8x16_Core2.fm - 256Mb DDR: Rev. O, Core DDR: Rev. B 1/09 EN 52 Micron Technology, Inc., reserves the right to change products or specifications without notice. ©2003 Micron Technology, Inc. All rights reserved. 256Mb: x4, x8, x16 DDR SDRAM Operations Figure 21: INITIALIZATION Flow Diagram Step 1 VDD and VDDQ ramp 2 Apply VREF and VTT 3 CKE must be LVCMOS LOW 4 Apply stable CLOCKs 5 Wait at least 200µs 6 Bring CKE HIGH with a NOP command 7 PRECHARGE ALL 8 Assert NOP or DESELECT for tRP time 9 Configure extended mode register 10 Assert NOP or DESELECT for tMRD time 11 Configure load mode register and reset DLL 12 Assert NOP or DESELECT for tMRD time 13 PRECHARGE ALL 14 Assert NOP or DESELECT for tRP time 15 Issue AUTO REFRESH command 16 Assert NOP or DESELECT commands for tRFC 17 Issue AUTO REFRESH command 18 Assert NOP or DESELECT for tRFC time 19 Optional LMR command to clear DLL bit 20 Assert NOP or DESELECT for tMRD time 21 DRAM is ready for any valid command PDF: 09005aef80768abb/Source: 09005aef82a95a3a DDR_x4x8x16_Core2.fm - 256Mb DDR: Rev. O, Core DDR: Rev. B 1/09 EN 53 Micron Technology, Inc., reserves the right to change products or specifications without notice. ©2003 Micron Technology, Inc. All rights reserved. 256Mb: x4, x8, x16 DDR SDRAM Operations Figure 22: VDD VDDQ VTT1 VREF CK# CK tVTD1 INITIALIZATION Timing Diagram (( )) (( )) (( )) (( )) T0 (( )) (( )) tIS LVCMOS LOW level ( ( )) (( )) (( )) (( )) (( )) (( )) (( )) (( )) (( )) (( )) (( )) (( )) (( )) T = 200µs Power-up: VDD and CK stable tRP tMRD tMRD Load extended mode register Load mode register5 tRP tRFC 200 cycles of CK4 Indicates A Break in Time Scale Don’t Care tRFC High-Z High-Z tIS tIH NOP tCK PRE tCH tIH tCL T1 (( )) (( )) (( )) (( )) (( )) (( )) (( )) (( )) tIS tIH (( )) (( )) All banks ( ( )) (( )) tIS tIH (( )) (( )) (( )) (( )) Ta0 (( )) (( )) (( )) (( )) (( )) (( )) (( )) (( )) (( )) (( )) (( )) (( )) (( )) (( )) (( )) (( )) Code3 Tb0 (( )) (( )) (( )) (( )) (( )) (( )) (( )) (( )) (( )) (( )) ( ( All banks )) (( )) tIS tIH (( )) (( )) (( )) (( )) Tc0 (( )) (( )) (( )) (( )) (( )) (( )) (( )) (( )) (( )) (( )) (( )) (( )) (( )) (( )) (( )) (( )) Td0 (( )) (( )) (( )) (( )) (( )) (( )) (( )) (( )) (( )) (( )) (( )) (( )) (( )) (( )) (( )) (( )) Te0 (( )) (( )) (( )) (( )) (( )) (( )) (( )) (( )) (( )) (( )) (( )) (( )) (( )) (( )) (( )) (( )) ACT2 Tf0 CKE Command LMR LMR PRE AR AR DM Address Code tIS tIH Code tIS tIH BA0 = 1 BA1 = 0 RA A10 Code RA BA0, BA1 BA0 = 0 BA1 = 0 BA DQS DQ Notes: 1. VTT is not applied directly to the device; however, tVTD ≥ 0 to avoid device latch-up. VDDQ, VTT, and VREF ≤ VDD + 0.3V. Alternatively, VTT may be 1.35V maximum during power-up, even if VDD/VDDQ are 0V, provided a minimum of 42Ω of series resistance is used between the VTT supply and the input pin. Once initialized, VREF must always be powered within the specified range. 2. Although not required by the Micron device, JEDEC specifies issuing another LMR command (A8 = 0) prior to activating any bank. If another LMR command is issued, the same, previously issued operating parameters must be used. 3. The two AUTO REFRESH commands at Td0 and Te0 may be applied following the LMR command at Ta0. 4. tMRD is required before any command can be applied (during MRD time only NOPs or DESELECTs are allowed), and 200 cycles of CK are required before a READ command can be issued. 5. While programming the operating parameters, reset the DLL with A8 = 1. PDF: 09005aef80768abb/Source: 09005aef82a95a3a DDR_x4x8x16_Core2.fm - 256Mb DDR: Rev. O, Core DDR: Rev. B 1/09 EN 54 Micron Technology, Inc., reserves the right to change products or specifications without notice. ©2003 Micron Technology, Inc. All rights reserved. 256Mb: x4, x8, x16 DDR SDRAM Operations REGISTER DEFINITION Mode Register The mode register is used to define the specific DDR SDRAM mode of operation. This definition includes the selection of a burst length, a burst type, a CAS latency, and an operating mode, as shown in Figure 23. The mode register is programmed via the LMR command (with BA0 = 0 and BA1 = 0) and will retain the stored information until it is programmed again or until the device loses power (except for bit A8, which is selfclearing). Reprogramming the mode register will not alter the contents of the memory, provided it is performed correctly. The mode register must be loaded (reloaded) when all banks are idle and no bursts are in progress, and the controller must wait the specified time before initiating the subsequent operation. Violating either of these requirements will result in unspecified operation. Mode register bits A0–A2 specify the burst length, A3 specifies the type of burst (sequential or interleaved), A4–A6 specify the CAS latency, and A7–An specify the operating mode. Figure 23: Mode Register Definition BA1 BA0 An . . . A9 A8 A7 A6 A5 A4 A3 A2 A1 A0 Address bus n + 2 n + 1 n1 . . . 0 0 9 8 7 6 5 4 3 2 1 0 Operating mode CAS Latency BT Burst length Mode register (Mx) M2 M1 M0 Burst Length Mn + 2 Mn + 1 Mode Register Definition 0 0 1 1 0 1 0 1 Base mode register Extended mode register Reserved Reserved M3 0 1 Burst Type Sequential Interleaved 0 0 0 0 1 1 Mn . . . M9 M8 M7 M6–M0 Operating Mode 0 0 – 0 0 – 0 0 – 0 1 – 0 0 – Valid Valid – Normal operation Normal operation/reset DLL All other states reserved M6 0 0 0 0 1 1 1 1 M5 0 0 1 1 0 0 1 1 M4 0 1 0 1 0 1 0 1 CAS Latency Reserved Reserved 2 3 (-5B only) Reserved Reserved 2.5 Reserved 1 1 0 0 1 1 0 0 1 1 0 1 0 1 0 1 0 1 Reserved 2 4 8 Reserved Reserved Reserved Reserved Notes: 1. n is the most significant row address bit from Table 2 on page 2. PDF: 09005aef80768abb/Source: 09005aef82a95a3a DDR_x4x8x16_Core2.fm - 256Mb DDR: Rev. O, Core DDR: Rev. B 1/09 EN 55 Micron Technology, Inc., reserves the right to change products or specifications without notice. ©2003 Micron Technology, Inc. All rights reserved. 256Mb: x4, x8, x16 DDR SDRAM Operations Burst Length (BL) Read and write accesses to the DDR SDRAM are burst oriented, with the burst length being programmable for both READ and WRITE bursts, as shown in Figure 23 on page 55. The burst length determines the maximum number of column locations that can be accessed for a given READ or WRITE command. BL = 2, BL = 4, or BL = 8 locations are available for both the sequential and the interleaved burst types. Reserved states should not be used, as unknown operation or incompatibility with future versions may result. When a READ or WRITE command is issued, a block of columns equal to the burst length is effectively selected. All accesses for that burst take place within this block— meaning that the burst will wrap within the block if a boundary is reached. The block is uniquely selected by A1–Ai when BL = 2, by A2–Ai when BL = 4, and by A3–Ai when BL = 8 (where Ai is the most significant column address bit for a given configuration). The remaining (least significant) address bit(s) is (are) used to select the starting location within the block. For example: for BL = 8, A3–Ai select the eight-data-element block; A0– A2 select the first access within the block. Burst Type Accesses within a given burst may be programmed to be either sequential or interleaved; this is referred to as the burst type and is selected via bit M3. The ordering of accesses within a burst is determined by the burst length, the burst type, and the starting column address, as shown in Table 34. Table 34: Burst Definition Order of Accesses Within a Burst Burst Length 2 Starting Column Address – – – – – – – – A2 0 0 0 0 1 1 1 1 – – – A1 0 0 1 1 A1 0 0 1 1 0 0 1 1 A0 0 1 A0 0 1 0 1 A0 0 1 0 1 0 1 0 1 Type = Sequential – 0-1 1-0 – 0-1-2-3 1-2-3-0 2-3-0-1 3-0-1-2 – 0-1-2-3-4-5-6-7 1-2-3-4-5-6-7-0 2-3-4-5-6-7-0-1 3-4-5-6-7-0-1-2 4-5-6-7-0-1-2-3 5-6-7-0-1-2-3-4 6-7-0-1-2-3-4-5 7-0-1-2-3-4-5-6 Type = Interleaved – 0-1 1-0 – 0-1-2-3 1-0-3-2 2-3-0-1 3-2-1-0 – 0-1-2-3-4-5-6-7 1-0-3-2-5-4-7-6 2-3-0-1-6-7-4-5 3-2-1-0-7-6-5-4 4-5-6-7-0-1-2-3 5-4-7-6-1-0-3-2 6-7-4-5-2-3-0-1 7-6-5-4-3-2-1-0 4 8 PDF: 09005aef80768abb/Source: 09005aef82a95a3a DDR_x4x8x16_Core2.fm - 256Mb DDR: Rev. O, Core DDR: Rev. B 1/09 EN 56 Micron Technology, Inc., reserves the right to change products or specifications without notice. ©2003 Micron Technology, Inc. All rights reserved. 256Mb: x4, x8, x16 DDR SDRAM Operations CAS Latency (CL) The CL is the delay, in clock cycles, between the registration of a READ command and the availability of the first bit of output data. The latency can be set to 2, 2.5, or 3 (-5B only) clocks, as shown in Figure 24. Reserved states should not be used, as unknown operation or incompatibility with future versions may result. If a READ command is registered at clock edge n, and the latency is m clocks, the data will be available nominally coincident with clock edge n + m. Table 35 on page 58 indicates the operating frequencies at which each CL setting can be used. Figure 24: CAS Latency T0 CK# CK Command READ NOP CL = 2 DQS DQ NOP NOP T1 T2 T2n T3 T3n T0 CK# CK Command READ T1 T2 T2n T3 T3n NOP CL = 2.5 NOP NOP DQS DQ T0 CK# CK Command READ T1 T2 T3 T3n NOP CL = 3 NOP NOP DQS DQ Transitioning Data Don’t Care Note: BL = 4 in the cases shown; shown with nominal tAC, tDQSCK, and tDQSQ. PDF: 09005aef80768abb/Source: 09005aef82a95a3a DDR_x4x8x16_Core2.fm - 256Mb DDR: Rev. O, Core DDR: Rev. B 1/09 EN 57 Micron Technology, Inc., reserves the right to change products or specifications without notice. ©2003 Micron Technology, Inc. All rights reserved. 256Mb: x4, x8, x16 DDR SDRAM Operations Table 35: CAS Latency Allowable Operating Clock Frequency (MHz) Speed -5B -6/-6T -75E -75Z -75 CL = 2 75 ≤ f ≤ 133 75 ≤ f ≤ 133 75 ≤ f ≤ 133 75 ≤ f ≤ 133 75 ≤ f ≤ 100 CL = 2.5 75 ≤ f ≤ 167 75 ≤ f ≤ 167 75 ≤ f ≤ 133 75 ≤ f ≤ 133 75 ≤ f ≤ 133 CL = 3 133 ≤ f ≤ 200 – – – – Operating Mode The normal operating mode is selected by issuing an LMR command with bits A7–An each set to zero and bits A0–A6 set to the desired values. A DLL reset is initiated by issuing an LMR command with bits A7 and A9–An each set to zero, bit A8 set to one, and bits A0–A6 set to the desired values. Although not required by the Micron device, JEDEC specifications recommend that an LMR command resetting the DLL should always be followed by an LMR command selecting normal operating mode. All other combinations of values for A7–An are reserved for future use and/or test modes. Test modes and reserved states should not be used, as unknown operation or incompatibility with future versions may result. Extended Mode Register The extended mode register controls functions beyond those controlled by the mode register; these additional functions are DLL enable/disable and output drive strength. These functions are controlled via the bits shown in Figure 25 on page 59. The extended mode register is programmed via the LMR command to the mode register (with BA0 = 1 and BA1 = 0) and will retain the stored information until it is programmed again or until the device loses power. The enabling of the DLL should always be followed by an LMR command to the mode register (BA0/BA1 = 0) to reset the DLL. The extended mode register must be loaded when all banks are idle and no bursts are in progress, and the controller must wait the specified time before initiating any subsequent operation. Violating either requirement could result in an unspecified operation. Output Drive Strength The normal drive strength for all outputs is specified to be SSTL_2, Class II. The Design Revision F and K devices support a programmable option for reduced drive. This option is intended for the support of the lighter load and/or point-to-point environments. The selection of the reduced drive strength will alter the DQ and DQS pins from SSTL_2, Class II drive strength to a reduced drive strength, which is approximately 54% of the SSTL_2, Class II drive strength. DLL Enable/Disable When the part is running without the DLL enabled, device functionality may be altered. The DLL must be enabled for normal operation. DLL enable is required during powerup initialization and upon returning to normal operation after having disabled the DLL for the purpose of debug or evaluation (when the device exits self refresh mode, the DLL is enabled automatically). Anytime the DLL is enabled, 200 clock cycles with CKE HIGH must occur before a READ command can be issued. PDF: 09005aef80768abb/Source: 09005aef82a95a3a DDR_x4x8x16_Core2.fm - 256Mb DDR: Rev. O, Core DDR: Rev. B 1/09 EN 58 Micron Technology, Inc., reserves the right to change products or specifications without notice. ©2003 Micron Technology, Inc. All rights reserved. 256Mb: x4, x8, x16 DDR SDRAM Operations Figure 25: Extended Mode Register Definition BA1 BA0 An . . . A9 A8 A7 A6 A5 A4 A3 A2 A1 A0 Address bus n + 2 n + 1 n1 . . . 9 8 7 6 5 Operating Mode 0 1 4 3 2 10 DS DLL Extended mode register (Ex) E0 0 Mn + 2 Mn + 1 0 0 1 1 0 1 0 1 Mode Register Definition Base mode register Extended mode register Reserved Reserved 3 E1 0 1 E1, E0 Valid – 2 1 DLL Enable Disable Drive Strength Normal Reduced Operating Mode Reserved Reserved En . . . E9 E8 E7 E6 E5 E4 E3 E2 0 – 0 – 0 – 0 – 0 – 0 – 0 – 0 – 0 – 0 – Notes: 1. n is the most significant row address bit from Table 2 on page 2. 2. The reduced drive strength option is available only on Design Revision F and K. 3. The QFC# option is not supported. ACTIVE After a row is opened with an ACTIVE command, a READ or WRITE command may be issued to that row, subject to the tRCD specification. tRCD (MIN) should be divided by the clock period and rounded up to the next whole number to determine the earliest clock edge after the ACTIVE command on which a READ or WRITE command can be entered. For example, a tRCD specification of 20ns with a 133 MHz clock (7.5ns period) results in 2.7 clocks rounded to 3. This is reflected in Figure 26 on page 60, which covers any case where 2 < tRCD (MIN)/tCK ≤ 3 (Figure 26 also shows the same case for tRRD; the same procedure is used to convert other specification limits from time units to clock cycles). A row remains active (or open) for accesses until a PRECHARGE command is issued to that bank. A PRECHARGE command must be issued before opening a different row in the same bank. A subsequent ACTIVE command to a different row in the same bank can only be issued after the previous active row has been “closed” (precharged). The minimum time interval between successive ACTIVE commands to the same bank is defined by tRC. A subsequent ACTIVE command to another bank can be issued while the first bank is being accessed, which results in a reduction of total row-access overhead. The minimum time interval between successive ACTIVE commands to different banks is defined by tRRD. PDF: 09005aef80768abb/Source: 09005aef82a95a3a DDR_x4x8x16_Core2.fm - 256Mb DDR: Rev. O, Core DDR: Rev. B 1/09 EN 59 Micron Technology, Inc., reserves the right to change products or specifications without notice. ©2003 Micron Technology, Inc. All rights reserved. 256Mb: x4, x8, x16 DDR SDRAM Operations Figure 26: CK# CK ACT ACT Example: Meeting tRCD (tRRD) MIN When 2 < tRCD (tRRD) MIN/tCK ≤ 3 T0 T1 T2 T3 T4 T5 T6 T7 Command NOP NOP NOP NOP RD/WR NOP Address Row Row Col BA0, BA1 Bank x Bank y Bank y tRRD tRCD Don’t Care READ During the READ command, the value on input A10 determines whether or not auto precharge is used. If auto precharge is selected, the row being accessed will be precharged at the end of the READ burst; if auto precharge is not selected, the row will remain open for subsequent accesses. Note: For the READ commands used in the following illustrations, auto precharge is disabled. During READ bursts, the valid data-out element from the starting column address will be available following the CL after the READ command. Each subsequent data-out element will be valid nominally at the next positive or negative clock edge (that is, at the next crossing of CK and CK#). Figure 27 on page 62 shows the general timing for each possible CL setting. DQS is driven by the DDR SDRAM along with output data. The initial LOW state on DQS is known as the read preamble; the LOW state coincident with the last data-out element is known as the read postamble. Upon completion of a burst, assuming no other commands have been initiated, the DQ will go High-Z. Detailed explanations of tDQSQ (valid data-out skew), tQH (data-out window hold), and the valid data window are depicted in Figure 35 on page 70 and Figure 36 on page 71. Detailed explanations of tDQSCK (DQS transition skew to CK) and t AC (data-out transition skew to CK) are depicted in Figure 37 on page 72. Data from any READ burst may be concatenated or truncated with data from a subsequent READ command. In either case, a continuous flow of data can be maintained. The first data element from the new burst follows either the last element of a completed burst or the last desired data element of a longer burst which is being truncated. The new READ command should be issued x cycles after the first READ command, where x equals the number of desired data element pairs (pairs are required by the 2n-prefetch architecture). This is shown in Figure 28 on page 63. A READ command can be initiated on any clock cycle following a previous READ command. Nonconsecutive read data is illustrated in Figure 29 on page 64. Full-speed random read accesses within a page (or pages) can be performed, as shown in Figure 30 on page 65. PDF: 09005aef80768abb/Source: 09005aef82a95a3a DDR_x4x8x16_Core2.fm - 256Mb DDR: Rev. O, Core DDR: Rev. B 1/09 EN 60 Micron Technology, Inc., reserves the right to change products or specifications without notice. ©2003 Micron Technology, Inc. All rights reserved. 256Mb: x4, x8, x16 DDR SDRAM Operations Data from any READ burst may be truncated with a BURST TERMINATE command, as shown in Figure 31 on page 66. The BURST TERMINATE latency is equal to the CL, that is, the BURST TERMINATE command should be issued x cycles after the READ command where x equals the number of desired data element pairs (pairs are required by the 2n-prefetch architecture). Data from any READ burst must be completed or truncated before a subsequent WRITE command can be issued. If truncation is necessary, the BURST TERMINATE command must be used, as shown in Figure 32 on page 67. The tDQSS (NOM) case is shown; the t DQSS (MAX) case has a longer bus idle time. (tDQSS [MIN] and tDQSS [MAX] are defined in the section on WRITEs.) A READ burst may be followed by, or truncated with, a PRECHARGE command to the same bank provided that auto precharge was not activated. The PRECHARGE command should be issued x cycles after the READ command, where x equals the number of desired data element pairs (pairs are required by the 2n-prefetch architecture). This is shown in Figure 33 on page 68. Following the PRECHARGE command, a subsequent command to the same bank cannot be issued until both tRAS and tRP have been met. Part of the row precharge time is hidden during the access of the last data elements. PDF: 09005aef80768abb/Source: 09005aef82a95a3a DDR_x4x8x16_Core2.fm - 256Mb DDR: Rev. O, Core DDR: Rev. B 1/09 EN 61 Micron Technology, Inc., reserves the right to change products or specifications without notice. ©2003 Micron Technology, Inc. All rights reserved. 256Mb: x4, x8, x16 DDR SDRAM Operations Figure 27: READ Burst CK# CK Command Address READ Bank a, Col n NOP NOP NOP NOP NOP T0 T1 T2 T2n T3 T3n T4 T5 CL = 2 DQS DQ DO n T0 CK# CK Command Address READ Bank a, Col n T1 T2 T2n T3 T3n T4 T5 NOP NOP NOP NOP NOP CL = 2.5 DQS DQ DO n T0 CK# CK Command Address READ Bank a, Col n T1 T2 T3 T3n T4 T4n T5 NOP NOP NOP NOP NOP CL = 3 DQS DO n DQ Transitioning Data Don’t Care Notes: 1. 2. 3. 4. DO n = data-out from column n. BL = 4. Three subsequent elements of data-out appear in the programmed order following DO n. Shown with nominal tAC, tDQSCK, and tDQSQ. PDF: 09005aef80768abb/Source: 09005aef82a95a3a DDR_x4x8x16_Core2.fm - 256Mb DDR: Rev. O, Core DDR: Rev. B 1/09 EN 62 Micron Technology, Inc., reserves the right to change products or specifications without notice. ©2003 Micron Technology, Inc. All rights reserved. 256Mb: x4, x8, x16 DDR SDRAM Operations Figure 28: Consecutive READ Bursts CK# CK Command Address READ Bank, Col n NOP READ Bank, Col b NOP NOP NOP T0 T1 T2 T2n T3 T3n T4 T4n T5 T5n CL = 2 DQS DQ DO n DO b CK# CK Command Address T0 T1 T2 T2n T3 T3n T4 T4n T5 T5n READ Bank, Col n NOP READ Bank, Col b NOP NOP NOP CL = 2.5 DQS DQ DO n DO b T0 CK# CK Command Address READ Bank, Col n T1 T2 T3 T3n T4 T4n T5 T5n NOP READ Bank, Col b NOP NOP NOP CL = 3 DQS DO n Transitioning Data DO b Don’t Care DQ Notes: 1. DO n (or b) = data-out from column n (or column b). 2. BL = 4 or BL = 8 (if BL = 4, the bursts are concatenated; if BL = 8, the second burst interrupts the first). 3. Three subsequent elements of data-out appear in the programmed order following DO n. 4. Three (or seven) subsequent elements of data-out appear in the programmed order following DO b. 5. Shown with nominal tAC, tDQSCK, and tDQSQ. 6. Example applies only when READ commands are issued to same device. PDF: 09005aef80768abb/Source: 09005aef82a95a3a DDR_x4x8x16_Core2.fm - 256Mb DDR: Rev. O, Core DDR: Rev. B 1/09 EN 63 Micron Technology, Inc., reserves the right to change products or specifications without notice. ©2003 Micron Technology, Inc. All rights reserved. 256Mb: x4, x8, x16 DDR SDRAM Operations Figure 29: Nonconsecutive READ Bursts T0 CK# CK Command Address READ Bank, Col n NOP NOP READ Bank, Col b NOP NOP NOP T1 T2 T2n T3 T3n T4 T5 T5n T6 CL = 2 DQS DQ DO n DO b T0 CK# CK Command Address READ Bank, Col n T1 T2 T2n T3 T3n T4 T5 T5n T6 NOP NOP READ Bank, Col b NOP NOP NOP CL = 2.5 DQS DO n DO b DQ T0 CK# CK Command Address READ Bank, Col n T1 T2 T3 T3n T4 T4n T5 T6 NOP NOP READ Bank, Col b NOP NOP NOP CL = 3 DQS DO n Transitioning Data DO b Don’t Care DQ Notes: 1. DO n (or b) = data-out from column n (or column b). 2. BL = 4 or BL = 8 (if BL = 4, the bursts are concatenated; if BL = 8, the second burst interrupts the first). 3. Three subsequent elements of data-out appear in the programmed order following DO n. 4. Three (or seven) subsequent elements of data-out appear in the programmed order following DO b. 5. Shown with nominal tAC, tDQSCK, and tDQSQ. PDF: 09005aef80768abb/Source: 09005aef82a95a3a DDR_x4x8x16_Core2.fm - 256Mb DDR: Rev. O, Core DDR: Rev. B 1/09 EN 64 Micron Technology, Inc., reserves the right to change products or specifications without notice. ©2003 Micron Technology, Inc. All rights reserved. 256Mb: x4, x8, x16 DDR SDRAM Operations Figure 30: Random READ Accesses CK# CK Command Address READ Bank, Col n READ Bank, Col x READ Bank, Col b READ Bank, Col g NOP NOP T0 T1 T2 T2n T3 T3n T4 T4n T5 T5n CL = 2 DQS DQ DO n DO n' DO x DO x' DO b DO b' DO g T0 CK# CK Command Address READ Bank, Col n T1 T2 T2n T3 T3n T4 T4n T5 T5n READ Bank, Col x READ Bank, Col b READ Bank, Col g NOP NOP CL = 2.5 DQS DO n DO n' DO x DO x' DO b DO b' DQ CK# CK Command Address T0 T1 T2 T3 T3n T4 T4n T5 T5n READ Bank, Col n READ Bank, Col x READ Bank, Col b READ Bank, Col g NOP NOP CL = 3 DQS DQ DO n DO n' DO x DO x' DO b DO b' Transitioning Data Don’t Care Notes: 1. 2. 3. 4. 5. DO n (or x or b or g) = data-out from column n (or column x or column b or column g). BL = 2, BL = 4, or BL = 8 (if BL = 4 or BL = 8, the following burst interrupts the previous). n', x', b', or g' indicate the next data-out following DO n, DO x, DO b, or DO g, respectively. READs are to an active row in any bank. Shown with nominal tAC, tDQSCK, and tDQSQ. PDF: 09005aef80768abb/Source: 09005aef82a95a3a DDR_x4x8x16_Core2.fm - 256Mb DDR: Rev. O, Core DDR: Rev. B 1/09 EN 65 Micron Technology, Inc., reserves the right to change products or specifications without notice. ©2003 Micron Technology, Inc. All rights reserved. 256Mb: x4, x8, x16 DDR SDRAM Operations Figure 31: Terminating a READ Burst T0 CK# CK Command Address READ Bank a, Col n BST1 NOP NOP NOP NOP T1 T2 T2n T3 T4 T5 CL = 2 DQS DQ DO n T0 CK# CK Command Address READ Bank a, Col n T1 T2 T2n T3 T4 T5 BST1 NOP NOP NOP NOP CL = 2.5 DQS DO n DQ T0 CK# CK Command Address READ Bank a, Col n T1 T2 T3 T3n T4 T5 BST1 NOP NOP NOP NOP CL = 3 DQS DO n Transitioning Data Don’t Care DQ Notes: 1. 2. 3. 4. 5. Page remains open. DO n = data-out from column n. BL = 4. Subsequent element of data-out appears in the programmed order following DO n. Shown with nominal tAC, tDQSCK, and tDQSQ. PDF: 09005aef80768abb/Source: 09005aef82a95a3a DDR_x4x8x16_Core2.fm - 256Mb DDR: Rev. O, Core DDR: Rev. B 1/09 EN 66 Micron Technology, Inc., reserves the right to change products or specifications without notice. ©2003 Micron Technology, Inc. All rights reserved. 256Mb: x4, x8, x16 DDR SDRAM Operations Figure 32: READ-to-WRITE T0 CK# CK Command Address READ Bank, Col n 1 BST NOP WRITE Bank, Col b NOP NOP T1 T2 T2n T3 T4 T4n T5 T5n CL = 2 DQS DQ DM DO n tDQSS (NOM) DI b T0 CK# CK Command Address READ Bank, Col n T1 T2 T2n T3 T3n T4 T5 T5n 1 BST NOP NOP WRITE Bank, Col b NOP CL = 2.5 DQS DO n tDQSS (NOM) DQ DM DI b T0 CK# CK Command Address READ Bank a, Col n T1 T2 T3 T3n T4 T5 T5n BST1 NOP NOP WRITE NOP CL = 3 DQS DO n tDQSS (NOM) DQ DM DI b Transitioning Data Don’t Care Notes: 1. 2. 3. 4. 5. 6. Page remains open. DO n = data-out from column n; DI b = data-in from column b. BL = 4 (applies for bursts of 8 as well; if BL = 2, the BURST command shown can be NOP). One subsequent element of data-out appears in the programmed order following DO n. Data-in elements are applied following DI b in the programmed order. Shown with nominal tAC, tDQSCK, and tDQSQ. PDF: 09005aef80768abb/Source: 09005aef82a95a3a DDR_x4x8x16_Core2.fm - 256Mb DDR: Rev. O, Core DDR: Rev. B 1/09 EN 67 Micron Technology, Inc., reserves the right to change products or specifications without notice. ©2003 Micron Technology, Inc. All rights reserved. 256Mb: x4, x8, x16 DDR SDRAM Operations Figure 33: READ-to-PRECHARGE T0 CK# CK Command Address READ Bank a, Col n NOP PRE Bank a, (a or all) NOP NOP ACT Bank a, Row T1 T2 T2n T3 T3n T4 T5 CL = 2 DQS DQ DO n tRP T0 CK# CK Command Address READ Bank a, Col n T1 T2 T2n T3 T3n T4 T5 NOP PRE Bank a, (a or all) NOP NOP ACT Bank a, Row CL = 2.5 DQS DQ DO n tRP T0 CK# CK Command Address READ Bank a, Col n T1 T2 T3 T3n T4 T4n T5 NOP PRE Bank a, (a or all) NOP NOP ACT Bank a, Row CL = 3 DQS tRP DQ DO n Transitioning Data Don’t Care Notes: 1. Provided tRAS (MIN) is met, a READ command with auto precharge enabled would cause a precharge to be performed at x number of clock cycles after the READ command, where x = BL/2. 2. DO n = data-out from column n. 3. BL = 4 or an interrupted burst of 8. 4. Three subsequent elements of data-out appear in the programmed order following DO n. 5. Shown with nominal tAC, tDQSCK, and tDQSQ. 6. READ-to-PRECHARGE equals two clocks, which allows two data pairs of data-out; it is also assumed that tRAS (MIN) is met. 7. An ACTIVE command to the same bank is only allowed if tRC (MIN) is met. PDF: 09005aef80768abb/Source: 09005aef82a95a3a DDR_x4x8x16_Core2.fm - 256Mb DDR: Rev. O, Core DDR: Rev. B 1/09 EN 68 Micron Technology, Inc., reserves the right to change products or specifications without notice. ©2003 Micron Technology, Inc. All rights reserved. 256Mb: x4, x8, x16 DDR SDRAM Operations Figure 34: CK# CK tIS tIH tCK tCH tCL Bank READ – Without Auto Precharge T0 T1 T2 T3 T4 T5 T5n T6 T6n T7 T8 CKE tIS Command tIH ACT tIS Address Row tIH Col n Row NOP 1 READ 2 NOP 1 PRE 3 1 NOP NOP 1 ACT 1 NOP tIS tIH All banks Row One bank A10 Row 4 tIS tIH Bank x tRCD Bank x 5 Bank x BA0, BA1 Bank x CL = 2 tRP tRAS3 tRC DM Case 1: tAC (MIN) and tDQSCK (MIN) DQS tLZ (MIN) tRPRE tDQSCK (MIN) tRPST DQ tLZ (MIN) DO n tAC (MIN) Case 2: tAC (MAX) and tDQSCK (MAX) DQS tRPRE tDQSCK (MAX) tRPST DQ DO n tAC (MAX) tHZ (MAX) Transitioning Data Don’t Care Notes: 1. NOP commands are shown for ease of illustration; other commands may be valid at these times. 2. BL = 4. 3. The PRECHARGE command can only be applied at T5 if tRAS (MIN) is met. 4. Disable auto precharge. 5. “Don’t Care” if A10 is HIGH at T5. 6. DO n (or b) = data-out from column n (or column b); subsequent elements are provided in the programmed order. 7. Refer to Figure 35 on page 70, Figure 36 on page 71, and Figure 37 on page 72 for detailed DQS and DQ timing. PDF: 09005aef80768abb/Source: 09005aef82a95a3a DDR_x4x8x16_Core2.fm - 256Mb DDR: Rev. O, Core DDR: Rev. B 1/09 EN 69 Micron Technology, Inc., reserves the right to change products or specifications without notice. ©2003 Micron Technology, Inc. All rights reserved. 256Mb: x4, x8, x16 DDR SDRAM Operations Figure 35: x4, x8 Data Output Timing – tDQSQ, tQH, and Data Valid Window T1 CK# CK tHP1 tHP1 tDQSQ2 tHP1 tDQSQ2 tHP1 tHP1 tDQSQ2 tHP1 tDQSQ2 T2 T2n T3 T3n T4 DQS 3 DQ (last data valid) DQ4 DQ4 DQ4 DQ4 DQ4 DQ4 DQ (first data no longer valid) tQH5 tQH5 tQH5 tQH5 DQ (last data valid) DQ (first data no longer valid) T2 T2 T2n T2n T3 T3 T3n T3n 6 All DQ and DQS collectively Earliest signal transition Latest signal transition T2 T2n T3 T3n Data valid window Data valid window Data valid window Data valid window Notes: 1. 2. 3. 4. 5. 6. tHP is the lesser of tCL or tCH clock transition collectively when a bank is active. is derived at each DQS clock edge, is not cumulative over time, begins with DQS transition, and ends with the last valid DQ transition. DQ transitioning after DQS transition define the tDQSQ window. DQS transitions at T2 and T2n are an “early DQS”; at T3, a “nominal DQS”; and at T3n, a “late DQS”. For a x4, only two DQ apply. t QH is derived from tHP: tQH = tHP - tQHS. The data valid window is derived for each DQS transitions and is defined as tQH - tDQSQ. tDQSQ PDF: 09005aef80768abb/Source: 09005aef82a95a3a DDR_x4x8x16_Core2.fm - 256Mb DDR: Rev. O, Core DDR: Rev. B 1/09 EN 70 Micron Technology, Inc., reserves the right to change products or specifications without notice. ©2003 Micron Technology, Inc. All rights reserved. 256Mb: x4, x8, x16 DDR SDRAM Operations Figure 36: x16 Data Output Timing – tDQSQ, tQH, and Data Valid Window T1 CK# CK tHP1 tHP1 tDQSQ2 tHP1 tDQSQ2 tHP1 tHP1 tDQSQ2 tHP1 tDQSQ2 T2 T2n T3 T3n T4 LDQS3 DQ (last data valid) 4 4 DQ 4 DQ 4 DQ 4 DQ 4 DQ 4 DQ 4 DQ (first data no longer valid) Lower byte tQH5 DQ (last data valid) DQ (first data no longer valid) 4 4 T2 T2 tQH5 T2n T2n tQH5 T3 T3 tQH5 T3n T3n DQ0–DQ7 and LDQS collectively 6 T2 T2n T3 T3n Data valid window tDQSQ2 Data valid window tDQSQ2 Data valid window tDQSQ2 tDQSQ2 Data valid window UDQS 3 DQ (last data valid) 7 7 DQ 7 DQ 7 DQ 7 DQ 7 DQ 7 DQ 7 DQ (first data no longer valid) Upper byte tQH5 DQ (last data valid) DQ (first data no longer valid) DQ8–DQ15 and UDQS collectively 7 7 6 T2 T2 tQH5 T2n T2n tQH5 T3 T3 tQH5 T3n T3n T2 T2n T3 T3n Data valid window Data valid window Data valid window Data valid window Notes: 1. 2. 3. 4. 5. 6. 7. t HP is the lesser of tCL or tCH clock transition collectively when a bank is active. is derived at each DQS clock edge, is not cumulative over time, begins with DQS transition, and ends with the last valid DQ transition. DQ transitioning after DQS transition define the tDQSQ window. LDQS defines the lower byte, and UDQS defines the upper byte. DQ0, DQ1, DQ2, DQ3, DQ4, DQ5, DQ6, or DQ7. tQH is derived from tHP: tQH = tHP - tQHS. The data valid window is derived for each DQS transition and is tQH - tDQSQ. DQ8, DQ9, DQ10, D11, DQ12, DQ13, DQ14, or DQ15. tDQSQ PDF: 09005aef80768abb/Source: 09005aef82a95a3a DDR_x4x8x16_Core2.fm - 256Mb DDR: Rev. O, Core DDR: Rev. B 1/09 EN 71 Micron Technology, Inc., reserves the right to change products or specifications without notice. ©2003 Micron Technology, Inc. All rights reserved. 256Mb: x4, x8, x16 DDR SDRAM Operations Figure 37: Data Output Timing – tAC and tDQSCK CK# CK tLZ (MIN) tRPRE tDQSCK2 (MAX) tDQSCK2 (MIN) T01 T1 T2 T2n T3 T3n T4 T4n T5 T5n T6 t tDQSCK2 (MAX) HZ (MAX) tDQSCK2 (MIN) tRPST DQS or LDQS/UDQS3 DQ (last data valid) DQ (first data valid) All DQ values collectively4 T2 T2 T2 tLZ (MIN) T2n T2n T2n T3 T3 T3 T3n T3n T3n T4 T4 T4 T4n T4n T4n T5 T5 T5 T5n T5n T5n tAC5 (MIN) tAC5 (MAX) tHZ (MAX) Notes: 1. READ command with CL = 2 issued at T0. 2. tDQSCK is the DQS output window relative to CK and is the “long term” component of the DQS skew. 3. DQ transitioning after DQS transition define the tDQSQ window. 4. All DQ must transition by tDQSQ after DQS transitions, regardless of tAC. 5. tAC is the DQ output window relative to CK and is the “long term” component of DQ skew. 6. tLZ (MIN) and tAC (MIN) are the first valid signal transitions. 7. tHZ (MAX) and tAC (MAX) are the latest valid signal transitions. WRITE During a WRITE command, the value on input A10 determines whether or not auto precharge is used. If auto precharge is selected, the row being accessed will be precharged at the end of the WRITE burst (after tWR time); if auto precharge is not selected, the row will remain open for subsequent accesses. Input data appearing on the DQ is written to the memory array subject to the DM input logic level appearing coincident with the data. If a given DM signal is registered LOW, the corresponding data will be written to memory. If the DM signal is registered HIGH, the corresponding data inputs will be ignored, and a WRITE will not be executed to that byte/column location. Note: For the WRITE commands used in the following illustrations, auto precharge is disabled. During WRITE bursts, the first valid data-in element will be registered on the first rising edge of DQS following the WRITE command, and subsequent data elements will be registered on successive edges of DQS. The LOW state on DQS between the WRITE command and the first rising edge is known as the write preamble; the LOW state on DQS following the last data-in element is known as the write postamble. The time between the WRITE command and the first corresponding rising edge of DQS (tDQSS) is specified with a relatively wide range (from 75% to 125% of one clock cycle). All of the WRITE diagrams show the nominal case, and where the two extreme cases (that is, tDQSS [MIN] and tDQSS [MAX]) might not be intuitive; they have also been included. Figure 38 on page 74 shows the nominal case and the extremes of tDQSS for BL = 4. Upon completion of a burst, assuming no other commands have been initiated, the DQ will remain High-Z and any additional input data will be ignored. PDF: 09005aef80768abb/Source: 09005aef82a95a3a DDR_x4x8x16_Core2.fm - 256Mb DDR: Rev. O, Core DDR: Rev. B 1/09 EN 72 Micron Technology, Inc., reserves the right to change products or specifications without notice. ©2003 Micron Technology, Inc. All rights reserved. 256Mb: x4, x8, x16 DDR SDRAM Operations Data for any WRITE burst may be concatenated with or truncated with a subsequent WRITE command. In either case, a continuous flow of input data can be maintained. The new WRITE command can be issued on any positive edge of clock following the previous WRITE command. The first data element from the new burst is applied after either the last element of a completed burst or the last desired data element of a longer burst which is being truncated. The new WRITE command should be issued x cycles after the first WRITE command, where x equals the number of desired data element pairs (pairs are required by the 2n-prefetch architecture). Figure 39 on page 75 shows concatenated bursts of 4. An example of nonconsecutive WRITEs is shown in Figure 40 on page 76. Full-speed random write accesses within a page or pages can be performed as shown in Figure 41 on page 76. Data for any WRITE burst may be followed by a subsequent READ command. To follow a WRITE without truncating the WRITE burst, tWTR should be met, as shown in Figure 42 on page 77. Data for any WRITE burst may be truncated by a subsequent READ command, as shown in Figure 43 on page 78. Note that only the data-in pairs that are registered prior to the tWTR period are written to the internal array, and any subsequent data-in should be masked with DM, as shown in Figure 44 on page 79. Data for any WRITE burst may be followed by a subsequent PRECHARGE command. To follow a WRITE without truncating the WRITE burst, tWR should be met, as shown in Figure 45 on page 80. Data for any WRITE burst may be truncated by a subsequent PRECHARGE command, as shown in Figure 46 on page 81 and Figure 47 on page 82. Only the data-in pairs registered prior to the tWR period are written to the internal array; any subsequent data-in should be masked with DM, as shown in Figures 46 and 47. After the PRECHARGE command, a subsequent command to the same bank cannot be issued until tRP is met. PDF: 09005aef80768abb/Source: 09005aef82a95a3a DDR_x4x8x16_Core2.fm - 256Mb DDR: Rev. O, Core DDR: Rev. B 1/09 EN 73 Micron Technology, Inc., reserves the right to change products or specifications without notice. ©2003 Micron Technology, Inc. All rights reserved. 256Mb: x4, x8, x16 DDR SDRAM Operations Figure 38: WRITE Burst T0 CK# CK Command Address tDQSS (NOM) DQS DQ DM tDQSS (MIN) DQS DQ DM tDQSS (MAX) DQS DQ DM tDQSS DI b tDQSS DI b tDQSS DI b WRITE Bank a, Col b NOP NOP NOP T1 T2 T2n T3 Transitioning Data Don’t Care Notes: 1. 2. 3. 4. DI b = data-in for column b. Three subsequent elements of data-in are applied in the programmed order following DI b. An uninterrupted burst of 4 is shown. A10 is LOW with the WRITE command (auto precharge is disabled). PDF: 09005aef80768abb/Source: 09005aef82a95a3a DDR_x4x8x16_Core2.fm - 256Mb DDR: Rev. O, Core DDR: Rev. B 1/09 EN 74 Micron Technology, Inc., reserves the right to change products or specifications without notice. ©2003 Micron Technology, Inc. All rights reserved. 256Mb: x4, x8, x16 DDR SDRAM Operations Figure 39: Consecutive WRITE-to-WRITE T0 CK# CK T1 T1n T2 T2n T3 T3n T4 T4n T5 Command WRITE NOP WRITE NOP NOP NOP Address tDQSS (NOM) DQS Bank, Col b tDQSS Bank, Col n DQ DI b DI n DM Transitioning Data Don’t Care Notes: 1. 2. 3. 4. 5. DI b (or n) = data-in from column b (or column n). Three subsequent elements of data-in are applied in the programmed order following DI b. Three subsequent elements of data-in are applied in the programmed order following DI n. An uninterrupted burst of 4 is shown. Each WRITE command may be to any bank. PDF: 09005aef80768abb/Source: 09005aef82a95a3a DDR_x4x8x16_Core2.fm - 256Mb DDR: Rev. O, Core DDR: Rev. B 1/09 EN 75 Micron Technology, Inc., reserves the right to change products or specifications without notice. ©2003 Micron Technology, Inc. All rights reserved. 256Mb: x4, x8, x16 DDR SDRAM Operations Figure 40: Nonconsecutive WRITE-to-WRITE T0 CK# CK T1 T1n T2 T2n T3 T4 T4n T5 T5n Command WRITE NOP NOP WRITE NOP NOP Address tDQSS (NOM) DQS Bank, Col b tDQSS Bank, Col n DQ DI b DI n DM Transitioning Data Don’t Care Notes: 1. 2. 3. 4. 5. DI b (or n) = data-in from column b (or column n). Three subsequent elements of data-in are applied in the programmed order following DI b. Three subsequent elements of data-in are applied in the programmed order following DI n. An uninterrupted burst of 4 is shown. Each WRITE command may be to any bank. Figure 41: Random WRITE Cycles T0 CK# CK T1 T1n T2 T2n T3 T3n T4 T4n T5 T5n Command WRITE WRITE WRITE WRITE WRITE NOP Address Bank, Col b Bank, Col x Bank, Col n Bank, Col a Bank, Col g tDQSS (NOM) DQS DQ DI b DI b' DI x DI x' DI n DI n' DI a DI a' DI g DI g' DM Transitioning Data Don’t Care Notes: 1. DI b (or x or n or a or g) = data-in from column b (or column x, or column n, or column a, or column g). 2. b', x', n', a' or g' indicate the next data-in following DO b, DO x, DO n, DO a, or DO g, respectively. 3. Programmed BL = 2, BL = 4, or BL = 8 in cases shown. 4. Each WRITE command may be to any bank. Micron Technology, Inc., reserves the right to change products or specifications without notice. ©2003 Micron Technology, Inc. All rights reserved. PDF: 09005aef80768abb/Source: 09005aef82a95a3a DDR_x4x8x16_Core2.fm - 256Mb DDR: Rev. O, Core DDR: Rev. B 1/09 EN 76 256Mb: x4, x8, x16 DDR SDRAM Operations Figure 42: CK# CK Command WRITE NOP NOP NOP tWTR READ NOP NOP WRITE-to-READ – Uninterrupting T0 T1 T1n T2 T2n T3 T4 T5 T6 T6n Address tDQSS (NOM) Bank a, Col b tDQSS Bank a, Col n CL = 2 DQS DQ DM tDQSS (MIN) tDQSS DI b DO n CL = 2 DQS DQ DM tDQSS (MAX) tDQSS DI b DO n CL = 2 DQS DQ DM DI b DO n Transitioning Data Don’t Care Notes: 1. 2. 3. 4. 5. DI b = data-in for column b; DO n = data-out for column n. Three subsequent elements of data-in are applied in the programmed order following DI b. An uninterrupted burst of 4 is shown. t WTR is referenced from the first positive CK edge after the last data-in pair. The READ and WRITE commands are to the same device. However, the READ and WRITE commands may be to different devices, in which case tWTR is not required, and the READ command could be applied earlier. 6. A10 is LOW with the WRITE command (auto precharge is disabled). PDF: 09005aef80768abb/Source: 09005aef82a95a3a DDR_x4x8x16_Core2.fm - 256Mb DDR: Rev. O, Core DDR: Rev. B 1/09 EN 77 Micron Technology, Inc., reserves the right to change products or specifications without notice. ©2003 Micron Technology, Inc. All rights reserved. 256Mb: x4, x8, x16 DDR SDRAM Operations Figure 43: CK# CK Command WRITE NOP NOP tWTR READ NOP NOP NOP WRITE-to-READ – Interrupting T0 T1 T1n T2 T2n T3 T3n T4 T5 T5n T6 T6n Address tDQSS (NOM) Bank a, Col b tDQSS Bank a, Col n CL = 2 DQS DQ DM tDQSS (MIN) tDQSS DI b DO n CL = 2 DQS DQ DM tDQSS (MAX) tDQSS DI b DO n CL = 2 DQS DQ DM DI b DO n Transitioning Data Don’t Care Notes: 1. 2. 3. 4. 5. 6. 7. DI b = data-in for column b; DO n = data-out for column n. An interrupted burst of 4 is shown; two data elements are written. One subsequent element of data-in is applied in the programmed order following DI b. tWTR is referenced from the first positive CK edge after the last data-in pair. A10 is LOW with the WRITE command (auto precharge is disabled). DQS is required at T2 and T2n (nominal case) to register DM. If the burst of 8 is used, DM and DQS are required at T3 and T3n because the READ command will not mask these two data elements. PDF: 09005aef80768abb/Source: 09005aef82a95a3a DDR_x4x8x16_Core2.fm - 256Mb DDR: Rev. O, Core DDR: Rev. B 1/09 EN 78 Micron Technology, Inc., reserves the right to change products or specifications without notice. ©2003 Micron Technology, Inc. All rights reserved. 256Mb: x4, x8, x16 DDR SDRAM Operations Figure 44: CK# CK Command WRITE NOP NOP tWTR Address tDQSS (NOM) DQS DQ DM tDQSS (MIN) DQS DQ DM tDQSS (MAX) DQS DQ DM DI b DO n tDQSS DI b DO n tDQSS DI b DO n Bank a, Col b tDQSS Bank a, Col n CL = 2 READ NOP NOP NOP WRITE-to-READ – Odd Number of Data, Interrupting T0 T1 T1n T2 T2n T3 T3n T4 T5 T5n T6 T6n CL = 2 CL = 2 Transitioning Data Don’t Care Notes: 1. 2. 3. DI b = data-in for column b; DO n = data-out for column n. An interrupted burst of 4 is shown; one data element is written. t WTR is referenced from the first positive CK edge after the last desired data-in pair (not the last two data elements). 4. A10 is LOW with the WRITE command (auto precharge is disabled). 5. DQS is required at T1n, T2, and T2n (nominal case) to register DM. 6. If the burst of 8 is used, DM and DQS are required at T3–T3n because the READ command will not mask these data elements. PDF: 09005aef80768abb/Source: 09005aef82a95a3a DDR_x4x8x16_Core2.fm - 256Mb DDR: Rev. O, Core DDR: Rev. B 1/09 EN 79 Micron Technology, Inc., reserves the right to change products or specifications without notice. ©2003 Micron Technology, Inc. All rights reserved. 256Mb: x4, x8, x16 DDR SDRAM Operations Figure 45: CK# CK Command WRITE NOP NOP NOP tWR Address tDQSS (NOM) DQS DI b Bank a, Col b tDQSS Bank, (a or all) NOP PRE tRP NOP WRITE-to-PRECHARGE – Uninterrupting T0 T1 T1n T2 T2n T3 T4 T5 T6 DQ DM tDQSS (MIN) DQS DI b tDQSS DQ DM tDQSS (MAX) DQS DI b tDQSS DQ DM Transitioning Data Don’t Care Notes: 1. 2. 3. 4. 5. DI b = data-in for column b. Three subsequent elements of data-in are applied in the programmed order following DI b. An uninterrupted burst of 4 is shown. t WR is referenced from the first positive CK edge after the last data-in pair. The PRECHARGE and WRITE commands are to the same device. However, the PRECHARGE and WRITE commands may be to different devices, in which case tWR is not required, and the PRECHARGE command could be applied earlier. 6. A10 is LOW with the WRITE command (auto precharge is disabled). PDF: 09005aef80768abb/Source: 09005aef82a95a3a DDR_x4x8x16_Core2.fm - 256Mb DDR: Rev. O, Core DDR: Rev. B 1/09 EN 80 Micron Technology, Inc., reserves the right to change products or specifications without notice. ©2003 Micron Technology, Inc. All rights reserved. 256Mb: x4, x8, x16 DDR SDRAM Operations Figure 46: CK# CK Command WRITE NOP NOP tWR Address tDQSS (NOM) DQS DI b Bank a, Col b tDQSS Bank, (a or all) NOP PRE NOP tRP NOP WRITE-to-PRECHARGE – Interrupting T0 T1 T1n T2 T2n T3 T3n T4 T4n T5 T6 DQ DM tDQSS (MIN) DQS DI b tDQSS DQ DM tDQSS (MAX) DQS tDQSS DQ DI b DM Transitioning Data Don’t Care Notes: 1. 2. 3. 4. 5. 6. 7. DI b = data-in for column b. Subsequent element of data-in is applied in the programmed order following DI b. An interrupted burst of 8 is shown; two data elements are written. t WR is referenced from the first positive CK edge after the last data-in pair. A10 is LOW with the WRITE command (auto precharge is disabled). DQS is required at T4 and T4n (nominal case) to register DM. If the burst of 4 is used, DQS and DM are not required at T3, T3n, T4, and T4n. PDF: 09005aef80768abb/Source: 09005aef82a95a3a DDR_x4x8x16_Core2.fm - 256Mb DDR: Rev. O, Core DDR: Rev. B 1/09 EN 81 Micron Technology, Inc., reserves the right to change products or specifications without notice. ©2003 Micron Technology, Inc. All rights reserved. 256Mb: x4, x8, x16 DDR SDRAM Operations Figure 47: CK# CK Command WRITE NOP NOP tWR Address tDQSS (NOM) DQS DI b Bank a, Col b tDQSS Bank, (a or all) NOP PRE NOP tRP NOP WRITE-to-PRECHARGE – Odd Number of Data, Interrupting T0 T1 T1n T2 T2n T3 T3n T4 T4n T5 T6 DQ DM tDQSS (MIN) DQS DI b tDQSS DQ DM tDQSS (MAX) DQS tDQSS DQ DM DI b Transitioning Data Don’t Care Notes: 1. 2. 3. 4. 5. 6. DI b = data-in for column b. An interrupted burst of 8 is shown; one data element is written. tWR is referenced from the first positive CK edge after the last data-in pair. A10 is LOW with the WRITE command (auto precharge is disabled). DQS is required at T4 and T4n (nominal case) to register DM. If the burst of 4 is used, DQS and DM are not required at T3, T3n, T4, and T4n. PDF: 09005aef80768abb/Source: 09005aef82a95a3a DDR_x4x8x16_Core2.fm - 256Mb DDR: Rev. O, Core DDR: Rev. B 1/09 EN 82 Micron Technology, Inc., reserves the right to change products or specifications without notice. ©2003 Micron Technology, Inc. All rights reserved. 256Mb: x4, x8, x16 DDR SDRAM Operations Figure 48: CK# CK tIS tIH tCK tCH tCL Bank WRITE – Without Auto Precharge T0 T1 T2 T3 T4 T4n T5 T5n T6 T7 T8 CKE tIS tIH ACT tIS tIH Col n tIS tIH NOP1 WRITE2 NOP1 NOP1 NOP1 NOP1 PRE Command NOP1 Address Row All banks A10 Row tIS tIH 3 One bank BA0, BA1 Bank x tRCD tRAS Bank x tWR Bank x4 tRP tDQSS (NOM) DQS tWPRES tWPRE tDQSL tDQSH tWPST DQ5 DM tDS DI b tDH Transitioning Data Don’t Care Notes: 1. NOP commands are shown for ease of illustration; other commands may be valid at these times. 2. BL = 4. 3. Disable auto precharge. 4. “Don’t Care” if A10 is HIGH at T8. 5. DI b = data-in from column b; subsequent elements are provided in the programmed order. 6. See Figure 50 on page 85 for detailed DQ timing. PDF: 09005aef80768abb/Source: 09005aef82a95a3a DDR_x4x8x16_Core2.fm - 256Mb DDR: Rev. O, Core DDR: Rev. B 1/09 EN 83 Micron Technology, Inc., reserves the right to change products or specifications without notice. ©2003 Micron Technology, Inc. All rights reserved. 256Mb: x4, x8, x16 DDR SDRAM Operations Figure 49: CK# CK tIS CKE tIS Command tIH ACT tIS Address Row tIH Col n tIS A10 Row tIS BA0, BA1 tIH Bank x tRCD tRAS tDQSS (NOM) DQS tWPRES tWPRE DQ 5 DI b tDQSL tDQSH tWPST tWR tRP 3 One bank 4 tIH 1 NOP WRITE 2 1 NOP 1 NOP 1 NOP 1 NOP PRE tIH tCK tCH tCL WRITE – DM Operation T0 T1 T2 T3 T4 T4n T5 T5n T6 T7 T8 1 NOP All banks Bank x Bank x DM tDS tDH Transitioning Data Don’t Care Notes: 1. NOP commands are shown for ease of illustration; other commands may be valid at these times. 2. BL = 4. 3. Disable auto precharge. 4. “Don’t Care” if A10 is HIGH at T8. 5. DI b = data-in from column b; subsequent elements are provided in the programmed order. 6. See Figure 50 on page 85 for detailed DQ timing. PDF: 09005aef80768abb/Source: 09005aef82a95a3a DDR_x4x8x16_Core2.fm - 256Mb DDR: Rev. O, Core DDR: Rev. B 1/09 EN 84 Micron Technology, Inc., reserves the right to change products or specifications without notice. ©2003 Micron Technology, Inc. All rights reserved. 256Mb: x4, x8, x16 DDR SDRAM Operations Figure 50: Data Input Timing T0 CK# CK tDQSS DQS tWPRES tWPRE DQ DM tDS tDH Transitioning Data Don’t Care DI b tDQSL tDQSH tWPST tDSH2 tDSS3 tDSH2 tDSS3 1 T1 T1n T2 T2n T3 Notes: 1. 2. 3. 4. 5. WRITE command issued at T0. (MIN) generally occurs during tDQSS (MIN). tDSS (MIN) generally occurs during tDQSS (MAX). For x16, LDQS controls the lower byte and UDQS controls the upper byte. DI b = data-in from column b. tDSH PRECHARGE The bank(s) will be available for a subsequent row access a specified time (tRP) after the PRECHARGE command is issued, except in the case of concurrent auto precharge. With concurrent auto precharge, a READ or WRITE command to a different bank is allowed as long as it does not interrupt the data transfer in the current bank and does not violate any other timing parameters. Input A10 determines whether one or all banks are to be precharged, and in the case where only one bank is to be precharged, inputs BA0, BA1 select the bank. When all banks are to be precharged, BA0, BA1 are treated as “Don’t Care.” Once a bank has been precharged, it is in the idle state and must be activated prior to any READ or WRITE commands being issued to that bank. A PRECHARGE command will be treated as a NOP if there is no open row in that bank (idle state), or if the previously open row is already in the process of precharging. Auto Precharge Auto precharge is a feature which performs the same individual-bank precharge function described above, but without requiring an explicit command. This is accomplished by using A10 to enable auto precharge in conjunction with a specific READ or WRITE command. A precharge of the bank/row that is addressed with the READ or WRITE command is automatically performed upon completion of the READ or WRITE burst. Auto precharge is either enabled or disabled for each individual READ or WRITE command. This device supports concurrent auto precharge if the command to the other bank does not interrupt the data transfer to the current bank. Auto precharge ensures that the precharge is initiated at the earliest valid stage within a burst. This “earliest valid stage” is determined as if an explicit PRECHARGE command was issued at the earliest possible time, without violating tRAS (MIN), as described for each burst type in “Operations” on page 52. The user must not issue another command to the same bank until the precharge time (tRP) is completed. PDF: 09005aef80768abb/Source: 09005aef82a95a3a DDR_x4x8x16_Core2.fm - 256Mb DDR: Rev. O, Core DDR: Rev. B 1/09 EN 85 Micron Technology, Inc., reserves the right to change products or specifications without notice. ©2003 Micron Technology, Inc. All rights reserved. 256Mb: x4, x8, x16 DDR SDRAM Operations Figure 51: CK# CK tIS CKE tIS Command NOP tIH 1 ACT tIS Address Row tIH Col n Row NOP 1 2,3 READ 1 NOP 1 NOP 1 NOP 1 NOP ACT tIH tCK tCH tCL Bank READ – with Auto Precharge T0 T1 T2 T3 T4 T5 T5n T6 T6n T7 T8 4 A10 Row tIS tIH Row IS BA0, BA1 IH Bank x tRCD, tRAP3 tRAS tRC CL = 2 tRP5 Bank x Bank x DM Case 1: tAC (MIN) and tDQSCK (MIN) tRPRE DQS tLZ (MIN) DQ 6 tLZ (MIN) Case 2: tAC (MAX) and tDQSCK (MAX) tRPRE DQS tDQSCK (MAX) tRPST DO n tAC (MIN) tDQSCK (MIN) tRPST DQ 6 DO n tAC (MAX) tHZ (MAX) Transitioning Data Don’t Care Notes: 1. NOP commands are shown for ease of illustration; other commands may be valid at these times. 2. BL = 4. 3. The READ command can only be applied at T3 if tRAP is satisfied at T3. 4. Enable auto precharge. 5. tRP starts only after tRAS has been satisfied. 6. DO n = data-out from column n; subsequent elements are provided in the programmed order. 7. Refer to Figure 35 on page 70, Figure 36 on page 71, and Figure 37 on page 72 for detailed DQS and DQ timing. PDF: 09005aef80768abb/Source: 09005aef82a95a3a DDR_x4x8x16_Core2.fm - 256Mb DDR: Rev. O, Core DDR: Rev. B 1/09 EN 86 Micron Technology, Inc., reserves the right to change products or specifications without notice. ©2003 Micron Technology, Inc. All rights reserved. 256Mb: x4, x8, x16 DDR SDRAM Operations Figure 52: CK# CK tIS CKE tIS Command tIH ACT tIS Address tIH Col n 3 A10 tIS BA0, BA1 Row tIH Bank x tRCD tRAS tDQSS (NOM) DQS tWPRES tWPRE 4 DI b tDQSL tDQSH tWPST tWR tRP tIS tIH NOP 1 WRITE 2 1 NOP 1 NOP NOP 1 1 NOP NOP 1 tIH tCK tCH tCL Bank WRITE – with Auto Precharge T0 T1 T2 T3 T4 T4n T5 T5n T6 T7 T8 1 NOP Row Bank x DQ DM tDS tDH Transitioning Data Don’t Care Notes: 1. NOP commands are shown for ease of illustration; other commands may be valid at these times. 2. BL = 4. 3. Enable auto precharge. 4. DI n = data-out from column n; subsequent elements are provided in the programmed order. 5. See Figure 50 on page 85 for detailed DQ timing. AUTO REFRESH During auto refresh, the addressing is generated by the internal refresh controller. This makes the address bits a “Don’t Care” during an AUTO REFRESH command. The DDR SDRAM requires AUTO REFRESH cycles at an average interval of tREFI (MAX). To allow for improved efficiency in scheduling and switching between tasks, some flexibility in the absolute refresh interval is provided. A maximum of eight AUTO REFRESH commands can be posted to any given DDR SDRAM, meaning that the maximum absolute interval between any AUTO REFRESH command and the next AUTO REFRESH command is 9 × tREFI(= tREFC). JEDEC specifications only support 8 × tREFI; Micron specifications exceed the JEDEC requirement by one clock. This maximum absolute interval is to allow future support for DLL updates, internal to the DDR SDRAM, to be restricted to AUTO REFRESH cycles, without allowing excessive drift in tAC between updates. PDF: 09005aef80768abb/Source: 09005aef82a95a3a DDR_x4x8x16_Core2.fm - 256Mb DDR: Rev. O, Core DDR: Rev. B 1/09 EN 87 Micron Technology, Inc., reserves the right to change products or specifications without notice. ©2003 Micron Technology, Inc. All rights reserved. 256Mb: x4, x8, x16 DDR SDRAM Operations Although not a JEDEC requirement, to provide for future functionality features, CKE must be active (HIGH) during the AUTO REFRESH period. The AUTO REFRESH period begins when the AUTO REFRESH command is registered and ends tRFC later. Figure 53: CK# CK CKE tIS Command tIH PRE NOP1 NOP1 AR NOP1 tIS tIH CK tCH Valid tCL Auto Refresh Mode T0 T1 T2 T3 T4 (( )) (( )) (( )) (( )) (( )) (( )) (( )) (( )) (( )) (( )) (( )) (( )) (( )) (( )) (( )) (( )) (( )) (( )) Ta0 Ta1 (( )) (( )) (( )) (( )) (( )) (( )) (( )) (( )) (( )) (( )) (( )) (( )) (( )) (( )) (( )) (( )) (( )) (( )) Tb0 Tb1 Tb2 Valid NOP1,2 NOP1 NOP1,2 AR3 ACT Address All banks RA A10 One bank RA tIS tIH BA0, BA1 5 Bank(s)4 BA DQS DQ 5 DM 5 tRP tRFC tRFC Don’t Care Notes: 1. NOP commands are shown for ease of illustration; other valid commands may be possible at these times. CKE must be active during clock-positive transitions. 2. NOP or COMMAND INHIBIT are the only commands allowed until after tRFC time; CKE must be active during clock-positive transitions. 3. The second AUTO REFRESH is not required and is only shown as an example of two back-toback AUTO REFRESH commands. 4. “Don’t Care” if A10 is HIGH at this point; A10 must be HIGH if more than one bank is active (that is, must precharge all active banks). 5. DM, DQ, and DQS signals are all “Don’t Care”/High-Z for the operations shown. SELF REFRESH When in the self refresh mode, the DDR SDRAM retains data without external clocking. The DLL is automatically disabled upon entering SELF REFRESH and is automatically enabled upon exiting SELF REFRESH (a DLL reset and 200 clock cycles must then occur before a READ command can be issued). Input signals except CKE are “Don’t Care” during SELF REFRESH. VREF voltage is also required for the full duration of SELF REFRESH. The procedure for exiting SELF REFRESH requires a sequence of commands. First, CK and CK# must be stable prior to CKE going back HIGH. Once CKE is HIGH, the DDR SDRAM must have NOP commands issued for tXSNR because time is required for the completion of any internal refresh in progress. A simple algorithm for meeting both refresh and DLL requirements is to apply NOPs for tXSRD time, then a DLL RESET (via PDF: 09005aef80768abb/Source: 09005aef82a95a3a DDR_x4x8x16_Core2.fm - 256Mb DDR: Rev. O, Core DDR: Rev. B 1/09 EN 88 Micron Technology, Inc., reserves the right to change products or specifications without notice. ©2003 Micron Technology, Inc. All rights reserved. 256Mb: x4, x8, x16 DDR SDRAM Operations the extended mode register) and NOPs for 200 additional clock cycles before applying a READ. Any command other than a READ can be performed tXSNR (MIN) after the DLL reset. NOP or DESELECT commands must be issued during the tXSNR (MIN) time. Self refresh is not supported on automotive tempature (AT) devices. Figure 54: CK# CK1 tIS CKE tIS Command2 tIH AR tCH tIH tCL tIS (( )) (( )) (( )) (( )) (( )) (( )) (( )) (( )) (( )) (( )) (( )) tRP4 tXSNR5 tXSRD6 Enter self refresh mode7 Exit self refresh mode7 Don’t Care Self Refresh Mode T0 T11 (( )) (( )) Ta01 Ta1 Ta2 (( )) (( )) t IS (( )) (( )) (( )) (( )) (( )) (( )) (( )) (( )) (( )) (( )) (( )) (( )) Tb1 Tb2 (( )) (( )) (( )) (( )) (( )) (( )) (( )) (( )) (( )) (( )) (( )) (( )) (( )) (( )) Tc1 tCK NOP NOP NOP Valid3 tIS tIH Valid Valid Address Valid Valid Valid DQS DQ DM Notes: 1. Clock must be stable until after the SELF REFRESH command has been registered. A change in clock frequency is allowed before Ta0, provided it is within the specified tCK limits. Regardless, the clock must be stable before exiting self refresh mode—that is, the clock must be cycling within specifications by Ta0. 2. NOPs are interchangeable with DESELECT commands. 3. AUTO REFRESH is not required at this point but is highly recommended. 4. Device must be in the all banks idle state prior to entering self refresh mode. 5. tXSNR is required before any non-READ command can be applied; that is only NOP or DESELECT commands are allowed until Tb1. 6. tXSRD (200 cycles of a valid clock with CKE = HIGH) is required before any READ command can be applied. 7. As a general rule, any time self refresh mode is exited, the DRAM may not re-enter the self refresh mode until all rows have been refreshed via the AUTO REFRESH command at the distributed refresh rate, tREFI, or faster. However, the self refresh mode may be re-entered anytime after exiting if each of the following conditions is met: 7a. The DRAM had been in the self refresh mode for a minimum of 200ms prior to exiting. 7b. tXSNR and tXSRD are not violated. 7c. At least two AUTO REFRESH commands are performed during each tREFI interval while the DRAM remains out of self refresh mode. 8. If the clock frequency is changed during self refresh mode, a DLL reset is required upon exit. 9. Once the device is initialized, VREF must always be powered within specified range. Micron Technology, Inc., reserves the right to change products or specifications without notice. ©2003 Micron Technology, Inc. All rights reserved. PDF: 09005aef80768abb/Source: 09005aef82a95a3a DDR_x4x8x16_Core2.fm - 256Mb DDR: Rev. O, Core DDR: Rev. B 1/09 EN 89 256Mb: x4, x8, x16 DDR SDRAM Operations Power-down (CKE Not Active) Unlike SDR SDRAMs, DDR SDRAMs require CKE to be active at all times an access is in progress, from the issuing of a READ or WRITE command, until completion of the access. Thus a clock suspend is not supported. For READs, an access completion is defined when the read postamble is satisfied; for WRITEs, when the write recovery time (tWR) is satisfied. Power-down, as shown in Figure 55 on page 91, is entered when CKE is registered LOW and all criteria in Table 33 on page 47 are met. If power-down occurs when all banks are idle, this mode is referred to as precharge power-down; if power-down occurs when a row is active in any bank, this mode is referred to as active power-down. Entering powerdown deactivates the input and output buffers, excluding CK, CK#, and CKE. For maximum power savings, the DLL is frozen during precharge power-down mode. Exiting power-down requires the device to be at the same voltage and frequency as when it entered power-down. However, power-down duration is limited by the refresh requirements of the device (tREFC or tREFCAT ). While in power-down, CKE LOW and a stable clock signal must be maintained at the inputs of the DDR SDRAM, while all other input signals are “Don’t Care.” The powerdown state is synchronously exited when CKE is registered HIGH (in conjunction with a NOP or DESELECT command). A valid executable command may be applied one clock cycle later. PDF: 09005aef80768abb/Source: 09005aef82a95a3a DDR_x4x8x16_Core2.fm - 256Mb DDR: Rev. O, Core DDR: Rev. B 1/09 EN 90 Micron Technology, Inc., reserves the right to change products or specifications without notice. ©2003 Micron Technology, Inc. All rights reserved. 256Mb: x4, x8, x16 DDR SDRAM Operations Figure 55: Power-Down Mode T0 CK# CK tIS tIH t CK tIS (( )) T1 T2 t CH tCL (( )) (( )) Ta0 Ta1 Ta2 tIS CKE 1 tIS tIH NOP Command Valid2 tIS tIH (( )) (( )) (( )) (( )) (( )) (( )) (( )) (( )) (( )) (( )) NOP Valid Address Valid Valid DQS DQ DM tREFC Enter 3 power-down mode Exit power-down mode Don’t Care Notes: 1. Once initialized, VREF must always be powered within the specified range. 2. If this command is a PRECHARGE (or if the device is already in the idle state), then the power-down mode shown is precharge power-down. If this command is an ACTIVE (or if at least one row is already active), then the power-down mode shown is active power-down. 3. No column accesses are allowed to be in progress at the time power-down is entered. 8000 S. Federal Way, P.O. Box 6, Boise, ID 83707-0006, Tel: 208-368-3900 www.micron.com/productsupport Customer Comment Line: 800-932-4992 Micron, the M logo, and the Micron logo are trademarks of Micron Technology, Inc.All other trademarks are the property of their respective owners. This data sheet contains minimum and maximum limits specified over the power supply and temperature range set forth herein. Although considered final, these specifications are subject to change, as further product development and data characterization sometimes occur. PDF: 09005aef80768abb/Source: 09005aef82a95a3a DDR_x4x8x16_Core2.fm - 256Mb DDR: Rev. O, Core DDR: Rev. B 1/09 EN 91 Micron Technology, Inc., reserves the right to change products or specifications without notice. ©2003 Micron Technology, Inc. All rights reserved.