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 Options • VDD = 2.5V ±0.2V; VDDQ = 2.5V ±0.2V VDD = 2.6V ±0.1V; VDDQ = 2.6V ±0.1V (DDR400)1 • 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 • Longer-lead TSOP for improved reliability (OCPL) • 2.5V I/O (SSTL_2-compatible) • Concurrent auto precharge option supported • tRAS lockout supported (tRAP = tRCD) • Configuration 64M4 – 64 Meg x 4 (16 Meg x 4 x 4 banks) 32M8 – 32 Meg x 8 (8 Meg x 8 x 4 banks) 16M16 – 16 Meg x 16 (4 Meg x 16 x 4 banks) • Plastic package – OCPL TG – 66-pin TSOP P – 66-pin TSOP (Pb-free) • Plastic package CV – 60-ball FBGA (8mm x 12.5mm) CY – 60-ball FBGA (8mm x 12.5mm) (Pb-free) • Timing – cycle time -5B – 5ns @ CL = 3 (DDR400) -62 – 6ns @ CL = 2.5 (DDR333) FBGA only -6T2 – 6ns @ CL = 2.5 (DDR333) TSOP only • Self refresh None – Standard L – Low-power self refresh • Temperature rating None – Commercial (0C to +70C) IT – Industrial (–40C to +85C) • Revision :K4 – x4, x8, x16 :M – x4, x8, x16 Notes: 1. DDR400 devices operating at < DDR333 conditions can use VDD/VDDQ = 2.5V +0.2V. 2. Available only on Revision K. 3. Available only on Revision M. 4. Not recommended for new designs. Table 1: Marking 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 CL = 2 CL = 2.5 CL = 3 Data-Out Window Access Window DQS–DQ Skew -5B -6 6T -75E/-75Z -75 133 133 133 133 100 167 167 167 133 133 200 n/a n/a n/a n/a 1.6ns 2.1ns 2.0ns 2.5ns 2.5ns ±0.70ns ±0.70ns ±0.70ns ±0.75ns ±0.75ns 0.40ns 0.40ns 0.45ns 0.50ns 0.50ns PDF: 09005aef80768abb/Source: 09005aef82a95a3a 256Mb_DDR_x4x8x16_D1.fm - 256Mb DDR: Rev. S, Core DDR: Rev. E 9/12 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 2: Addressing Parameter Configuration Refresh count Row address Bank address Column address Table 3: Marking 1 64 Meg x 4 32 Meg x 8 16 Meg x 16 16 Meg x 4 x 4 banks 8K 8K (A[12:0]) 4 (BA[1:0]) 2K (A[9:0], A11) 8 Meg x 8 x 4 banks 8K 8K (A[12:0]) 4 (BA[1:0]) 1K (A[9:0]) 4 Meg x 16 x 4 banks 8K 8K (A[12:0]) 4 (BA[1:0]) 512 (A[8:0]) 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) -5B Yes Yes Yes Yes Yes Yes -6 – Yes Yes Yes Yes Yes -6T – Yes Yes Yes Yes Yes -75E – – Yes Yes Yes Yes -75Z – – – Yes Yes Yes -75 – – – – Yes Yes -5B -6/-6T -75E -75Z -75 -75 Notes: Figure 1: 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. 256Mb DDR SDRAM Part Numbers Example Part Number: MT46V16M16P-6T:M MT46V Configuration Package Speed : Sp. Temp. Revision Op. Revision Configuration 64 Meg x 4 64M4 :K x4, x8, x16 32 Meg x 8 32M8 :M x4, x8, x16 16 Meg x 16 16M16 Package 400-mil TSOP Operating Temp. Commercial TG 400-mil TSOP (Pb-free) P 8mm x 12.5mm FBGA CV 8mm x 12.5mm FBGA (Pb-free) CY IT Industrial Special Options Standard L -6 Speed Grade tCK = 5ns, CL = 3 tCK = 6ns, CL = 2.5 -6T tCK = 6ns, CL = 2.5 -5B PDF: 09005aef80768abb/Source: 09005aef82a95a3a 256Mb_DDR_x4x8x16_D1.fm - 256Mb DDR: Rev. S, Core DDR: Rev. E 9/12 EN 2 Low power 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 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. S, Core DDR: Rev. E 9/12 EN 3 Micron Technology, Inc., reserves the right to change products or specifications without notice. ©2003 Micron Technology, Inc. All rights reserved. 256Mb: x4, x8, x16 DDR SDRAM Table of Contents Table of Contents Features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1 State Diagram. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7 Functional Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .8 General Notes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .8 Functional Block Diagrams. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9 Pin and Ball Assignments and Descriptions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .11 Package Dimensions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .14 Electrical Specifications – IDD . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .16 Electrical Specifications – DC and AC. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .18 Notes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .35 Commands . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .43 DESELECT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .47 NO OPERATION (NOP). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .47 LOAD MODE REGISTER (LMR) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .47 ACTIVE (ACT) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .48 READ . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .49 WRITE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .50 PRECHARGE (PRE) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .51 BURST TERMINATE (BST) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .51 AUTO REFRESH (AR). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .51 SELF REFRESH . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .51 Operations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .52 INITIALIZATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .52 REGISTER DEFINITION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .55 ACTIVE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .59 READ . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .60 WRITE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .72 PRECHARGE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .85 AUTO REFRESH . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .87 SELF REFRESH . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .88 Power-down (CKE Not Active) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .90 PDF: 09005aef80768abb/Source: 09005aef82a95a3a 256Mb_DDRTOC.fm - 256Mb DDR: Rev. S, Core DDR: Rev. E 9/12 EN 4 Micron Technology, Inc., reserves the right to change products or specifications without notice. ©2003 Micron Technology, Inc. All rights reserved. 256Mb: x4, x8, x16 DDR SDRAM List of Figures List of Figures Figure 1: Figure 2: Figure 6: Figure 9: Figure 10: Figure 11: Figure 12: Figure 13: Figure 14: Figure 15: Figure 16: Figure 17: Figure 18: Figure 19: Figure 20: Figure 21: Figure 22: Figure 23: Figure 24: Figure 25: Figure 26: Figure 29: Figure 30: Figure 31: Figure 32: Figure 33: Figure 34: Figure 35: Figure 36: Figure 37: Figure 38: Figure 39: Figure 41: Figure 42: Figure 43: Figure 44: Figure 45: Figure 46: Figure 47: Figure 48: Figure 49: Figure 50: Figure 51: Figure 52: Figure 53: Figure 54: 256Mb DDR SDRAM Part Numbers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2 Simplified State Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7 66-Pin TSOP Pin Assignments (Top View) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .11 60-Ball FBGA (8mm x 12.5mm) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .15 Input Voltage Waveform . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .20 SSTL_2 Clock Input . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .21 Derating Data Valid Window (tQH – tDQSQ) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .37 Full Drive Pull-Down Characteristics. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .38 Full Drive Pull-Up Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .38 Reduced Drive Pull-Down Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .39 Reduced Drive Pull-Up Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .39 Activating a Specific Row in a Specific Bank. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .48 READ Command. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .49 WRITE Command. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .50 PRECHARGE Command . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .51 INITIALIZATION Flow Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .53 INITIALIZATION Timing Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .54 Mode Register Definition . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .55 CAS Latency . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .57 Extended Mode Register Definition . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .59 Example: Meeting tRCD (tRRD) MIN When 2 < tRCD (tRRD) MIN/tCK 3 . . . . . . . . . . . . . . . . . . . . . .60 Nonconsecutive READ Bursts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .64 Random READ Accesses . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .65 Terminating a READ Burst . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .66 READ-to-WRITE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .67 READ-to-PRECHARGE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .68 Bank READ – Without Auto Precharge . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .69 x4, x8 Data Output Timing – tDQSQ, tQH, and Data Valid Window . . . . . . . . . . . . . . . . . . . . . . . . . . . .70 x16 Data Output Timing – tDQSQ, tQH, and Data Valid Window . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .71 Data Output Timing – tAC and tDQSCK. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .72 WRITE Burst. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .74 Consecutive WRITE-to-WRITE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .75 Random WRITE Cycles . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .76 WRITE-to-READ – Uninterrupting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .77 WRITE-to-READ – Interrupting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .78 WRITE-to-READ – Odd Number of Data, Interrupting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .79 WRITE-to-PRECHARGE – Uninterrupting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .80 WRITE-to-PRECHARGE – Interrupting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .81 WRITE-to-PRECHARGE – Odd Number of Data, Interrupting. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .82 Bank WRITE – Without Auto Precharge. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .83 WRITE – DM Operation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .84 Data Input Timing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .85 Bank READ – with Auto Precharge . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .86 Bank WRITE – with Auto Precharge . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .87 Auto Refresh Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .88 Self Refresh Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .89 PDF: 09005aef80768abb/Source: 09005aef82a95a3a 256Mb_DDRLOF.fm - 256Mb DDR: Rev. S, Core DDR: Rev. E 9/12 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 List of Tables List of Tables Table 1: Table 2: Table 3: Table 4: Table 5: Table 6: Table 7: Table 8: Table 9: Table 10: Table 11: Table 12: Table 13: Table 14: Table 15: Table 16: Table 17: Table 18: Table 19: Table 20: Table 21: Table 22: Table 23: Table 24: Table 25: Table 26: Table 27: Table 28: Table 29: Table 30: Table 31: Table 32: Table 33: Key Timing Parameters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1 Addressing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2 Speed Grade Compatibility . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2 Pin and Ball Descriptions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .13 IDD Specifications and Conditions (x4, x8, x16: -5B, -6, -6T) – Die Revision K . . . . . . . . . . . . . . . . . . .16 IDD Specifications and Conditions (x4, x8, x16: -5B, -6, -6T) – Die Revision M. . . . . . . . . . . . . . . . . . .17 Absolute Maximum Ratings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .18 DC Electrical Characteristics and Operating Conditions (-5B). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .18 DC Electrical Characteristics and Operating Conditions (-6, -6T, -75E, -75Z, -75) . . . . . . . . . . . . . . .19 AC Input Operating Conditions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .19 Clock Input Operating Conditions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .21 Capacitance (x4, x8 TSOP) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .22 Capacitance (x4, x8 FBGA) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .22 Capacitance (x16 TSOP) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .22 Capacitance (x16 FBGA) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .22 Electrical Characteristics and Recommended AC Operating Conditions (-5B) . . . . . . . . . . . . . . . . . .23 Electrical Characteristics and Recommended AC Operating Conditions (-6). . . . . . . . . . . . . . . . . . . .25 Electrical Characteristics and Recommended AC Operating Conditions (-6T) . . . . . . . . . . . . . . . . . .27 Electrical Characteristics and Recommended AC Operating Conditions (-75E) . . . . . . . . . . . . . . . . .29 Electrical Characteristics and Recommended AC Operating Conditions (-75Z) . . . . . . . . . . . . . . . . .31 Electrical Characteristics and Recommended AC Operating Conditions (-75) . . . . . . . . . . . . . . . . . .33 Input Slew Rate Derating Values for Addresses and Commands . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .34 Input Slew Rate Derating Values for DQ, DQS, and DM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .34 Normal Output Drive Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .41 Reduced Output Drive Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .42 Truth Table 1 – Commands . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .43 Truth Table 2 – DM Operation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .43 Truth Table 3 – Current State Bank n – Command to Bank n . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .44 Truth Table 4 – Current State Bank n – Command to Bank m . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .45 Command Delays . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .46 Truth Table 5 – CKE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .47 Burst Definition. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .56 CAS Latency . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .58 PDF: 09005aef80768abb/Source: 09005aef82a95a3a 256Mb_DDRLOT.fm - 256Mb DDR: Rev. S, Core DDR: Rev. E 9/12 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 State Diagram State Diagram Figure 1: Simplified State Diagram Power on Power applied PRE Precharge all banks Self refresh LMR REFS REFSX Idle REFA all banks precharged CKEL LMR MR EMR Auto refresh CKEH Active powerdown Precharge powerdown ACT CKE HIGH CKE LOW Row active Burst stop READ WRITE BST WRITE WRITE A READ A READ Write WRITE A READ A PRE Write A READ Read READ A PRE PRE Read A Precharge PREALL PRE 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 Note: 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 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. S, Core DDR: Rev. E 9/12 EN 7 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 (DQ[7:0]) DM refers to LDM and DQS refers to LDQS. For the upper byte (DQ[15:8]) DM refers to UDM and DQS refers to UDQS. • Complete functionality is described throughout the document and any page or diagram may have been simplified to convey a topic and may not be inclusive of all requirements. • Any specific requirement takes precedence over a general statement. PDF: 09005aef80768abb/Source: 09005aef82a95a3a DDR_x4x8x16_Core1.fm - 256Mb DDR: Rev. S, Core DDR: Rev. E 9/12 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 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 1: 64 Meg x 4 Functional Block Diagram CKE CK# CK Command decode CS# WE# CAS# RAS# Control logic Bank 3 Bank 2 Bank 1 Mode registers Refresh counter 15 13 Rowaddress MUX 13 13 Bank 0 rowaddress latch and decoder 8192 CK Bank 0 memory array (8192 x 1024 x 8) Data DLL 4 8 READ latch Sense amplifiers 4 MUX Drivers 4 1 DQS generator 8192 DQ[3:0] Column 0 2 A[12:0], BA[1:0] 15 Address register 2 I/O gating DM mask logic 1 DQS 1 Mask 1024 (x8) Column decoder 11 8 Bank control logic Columnaddress counter/ latch DQS Input registers 10 8 WRITE FIFO and drivers CK out 1 1 1 4 4 4 4 2 8 CK in Rcvrs DM 4 Data CK 1 Column 0 1 PDF: 09005aef80768abb/Source: 09005aef82a95a3a 256Mb_DDR_x4x8x16_D2.fm - 256Mb DDR: Rev. S, Core DDR: Rev. E 9/12 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 Functional Block Diagrams Figure 2: 32 Meg x 8 Functional Block Diagram CKE CK# CK CONTROL LOGIC COMMAND DECODE CS# WE# CAS# RAS# BANK3 BANK2 BANK1 MODE REGISTERS REFRESH 13 COUNTER 15 ROWADDRESS MUX BANK0 ROWADDRESS LATCH & DECODER 13 13 8192 CK BANK0 MEMORY ARRAY (8192 x 512 x 16) DLL DATA 8 16 READ LATCH SENSE AMPLIFIERS 8 MUX DRVRS 8 1 DQS GENERATOR 8192 DQ[7:0] I/O GATING DM MASK LOGIC 2 A[12:0], BA[1:0] ADDRESS REGISTER 15 COL0 BANK CONTROL LOGIC 2 DQS 1 1 1 1 8 8 8 8 MASK WRITE FIFO & DRIVERS 16 512 (x16) CK Out COLUMN DECODER COLUMNADDRESS COUNTER/ LATCH 10 DQS INPUT REGISTERS 16 9 1 2 RCVRS 16 CK In DM 8 DATA CK 1 COL0 1 Figure 3: 16 Meg x 16 Functional Block Diagram CKE CK# CK COMMAND DECODE CS# WE# CAS# RAS# CONTROL LOGIC BANK3 BANK2 BANK1 REFRESH COUNTER 13 MODE REGISTERS ROWADDRESS MUX 15 13 13 BANK0 ROWADDRESS LATCH & DECODER 8192 CK BANK0 MEMORY ARRAY (8192 x 256 x 32) 16 32 READ LATCH SENSE AMPLIFIERS 16 MUX DRVRS 16 2 DQS GENERATOR 8192 DQ[15:0] COL0 I/O GATING DM MASK LOGIC 2 A[12:0], BA[1:0] 15 ADDRESS REGISTER 2 2 COLUMN DECODER 8 32 WRITE FIFO & DRIVERS CK Out CK In LDQS UDQS 2 MASK 256 (x32) 9 DQS INPUT REGISTERS 32 BANK CONTROL LOGIC COLUMNADDRESS COUNTER/ LATCH DLL DATA 2 2 2 16 16 16 16 4 32 RCVRS 16 LDM, UDM DATA CK 2 COL0 1 PDF: 09005aef80768abb/Source: 09005aef82a95a3a 256Mb_DDR_x4x8x16_D2.fm - 256Mb DDR: Rev. S, Core DDR: Rev. E 9/12 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 Pin and Ball Assignments and Descriptions Figure 4: 66-Pin TSOP Pin Assignments (Top View) x4 x16 x8 VDD VDD VDD NF DQ0 DQ0 VDDQ VDDQ VDDQ NC NC DQ1 DQ0 DQ1 DQ2 VSSQ VSSQ VSSQ NC NC DQ3 NF DQ2 DQ4 VDDQ VDDQ VDDQ NC NC DQ5 DQ1 DQ3 DQ6 VSSQ VSSQ VSSQ NC NC DQ7 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 PDF: 09005aef80768abb/Source: 09005aef82a95a3a 256Mb_DDR_x4x8x16_D2.fm - 256Mb DDR: Rev. S, Core DDR: Rev. E 9/12 EN 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 11 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 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 5: 60-Ball FBGA Ball Assignments (Top View) x4 (Top View) 1 2 3 4 NF VSSQ VSS NC VDDQ DQ3 VSSQ NC NF NC VDDQ DQ2 VSSQ DQS NC DM VREF VSS CK CK# A12 CKE A11 A9 A8 A7 A6 A5 A4 VSS 5 6 7 VDD DQ0 NF DQ1 NC NC WE# RAS# BA1 A0 A2 VDD A B C D E F G H J K L M 8 9 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 VSSQ DQ7 VSS NC VDDQ DQ6 VSSQ DQ5 NC NC VDDQ DQ4 VSSQ DQS NC DM VREF VSS CK CK# A12 CKE A11 A9 A8 A7 A6 A5 A4 VSS 5 6 7 VDD DQ1 DQ2 DQ3 NC NC WE# RAS# BA1 A0 A2 VDD A B C D E F G H J K L M 8 9 DQ0 VDDQ VSSQ NC VDDQ NC VSSQ NC VDDQ NC VDD DNU CAS# CS# BA0 A10 A1 A3 x16 (Top View) 1 2 3 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 PDF: 09005aef80768abb/Source: 09005aef82a95a3a 256Mb_DDR_x4x8x16_D2.fm - 256Mb DDR: Rev. S, Core DDR: Rev. E 9/12 EN 4 5 6 A B C D E F G H J K L M 12 7 8 VDD DQ2 DQ4 DQ6 LDQS LDM WE# RAS# BA1 A0 A2 VDD DQ0 VSSQ VDDQ VSSQ VDDQ VDD CAS# CS# BA0 A10 A1 A3 9 VDDQ DQ1 DQ3 DQ5 DQ7 DNU 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 1: Pin and Ball Descriptions Symbol Type Description A[12:0] Input BA[1:0] Input CK, CK# Input CKE Input CS# Input DM LDM, UDM Input RAS#, CAS#, WE# DQ[15:0] DQ[7:0] DQ[3:0] DQS LDQS, UDQS Input 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 BA[1:0]) or all banks (A10 HIGH). The address inputs also provide the op-code during a LOAD MODE REGISTER command. Bank address inputs: BA[1:0] define to which bank an ACTIVE, READ, WRITE, or PRECHARGE command is being applied. BA[1:0] also define which mode register (mode register or extended mode register) is loaded during the LOAD MODE REGISTER (LMR) command. 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 POWERDOWN. 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 x16 devices, LDM is DM for DQ[7:0], and UDM is DM for DQ[15:8]. Pin 20 is NC on x4 and x8 devices. Command inputs: RAS#, CAS#, and WE# (along with CS#) define the command being entered. VDD VDDQ VSS VSSQ VREF Supply Supply Supply Supply Supply – – NC DNU I/O I/O I/O I/O Data input/output: Data bus for x16 devices. Data input/output: Data bus for x8 devices. Data input/output: Data bus for x4 devices. 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 x16 devices, LDQS is DQS for DQ[7:0], and UDQS is DQS for DQ[15:8]. Pin 16 (E7) is NC for x4 and x8 devices. 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, x8, x4: These pins should be left unconnected. Do not use: Must float to minimize noise on VREF. PDF: 09005aef80768abb/Source: 09005aef82a95a3a 256Mb_DDR_x4x8x16_D2.fm - 256Mb DDR: Rev. S, Core DDR: Rev. E 9/12 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 6: 66-Pin Plastic TSOP (400 mil) SEE DETAIL A 22.22 ± 0.08 0.71 0.65 TYP 0.10 (2X) 0.32 ±0.075 TYP 11.76 ± 0.20 10.16 ±0.08 +0.03 0.15 –0.02 PIN #1 ID GAGE PLANE 0.10 0.25 +0.10 –0.05 0.10 0.80 TYP 1.20 MAX 0.50 ±0.10 DETAIL A Notes: 1. All dimensions in millimeters. 2. Package width and length do not include mold protrusion; allowable mold protrusion is 0.25mm per side. PDF: 09005aef80768abb/Source: 09005aef82a95a3a 256Mb_DDR_x4x8x16_D2.fm - 256Mb DDR: Rev. S, Core DDR: Rev. E 9/12 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 7: 60-Ball FBGA (8mm x 12.5mm) 0.8 ±0.1 Seating plane A 0.12 A 60X Ø0.45 Solder ball material: eutectic or SAC305. Dimensions apply to solder balls postreflow on Ø0.33 NSMD ball pads. 9 8 7 Ball A1 ID 3 2 1 Ball A1 ID A B C D E F 11 CTR G 12.5 ±0.15 H J 1 TYP K L M 0.8 TYP 1.20 MAX 6.4 CTR 0.25 MIN 8 ±0.15 Notes: 1. All dimensions are in millimeters. 2. Topside part marking decoder can be found on Micron’s Web site. PDF: 09005aef80768abb/Source: 09005aef82a95a3a 256Mb_DDR_x4x8x16_D2.fm - 256Mb DDR: Rev. S, Core DDR: Rev. E 9/12 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 Electrical Specifications – IDD Electrical Specifications – IDD Table 2: IDD Specifications and Conditions (x4, x8, x16: -5B, -6, -6T) – Die Revision K 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 1 on page 18 Parameter/Condition Operating one-bank precharge current: tRC = tRC (MIN); 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 PDF: 09005aef80768abb/Source: 09005aef82a95a3a 256Mb_DDR_x4x8x16_D2.fm - 256Mb DDR: Rev. S, Core DDR: Rev. E 9/12 EN 16 Symbol -5B -6/6T Units Notes IDD0 100 90 mA 23, 48 IDD1 120 115 mA 23, 48 IDD2P 4 4 mA 24, 33 IDD2F 50 50 mA 51 IDD3P 35 30 mA 24, 33 IDD3N 60 55 mA 23 IDD4R 180 160 mA 23, 48 IDD4W 180 160 mA 23 IDD5 160 6 4 2 290 160 6 4 2 270 mA mA mA mA mA 50 28, 50 12 12 23, 49 IDD5A IDD6 IDD6A IDD7 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 3: IDD Specifications and Conditions (x4, x8, x16: -5B, -6, -6T) – Die Revision M 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 1 on page 18 Parameter/Condition tRC tRC = (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 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 PDF: 09005aef80768abb/Source: 09005aef82a95a3a 256Mb_DDR_x4x8x16_D2.fm - 256Mb DDR: Rev. S, Core DDR: Rev. E 9/12 EN 17 Symbol -5B -6/6T Units Notes IDD0 75 65 mA 23, 48 IDD1 85 75 mA 23, 48 IDD2P 4 4 mA 24, 33 IDD2F 23 23 mA 51 IDD3P 14 14 mA 24, 33 IDD3N 30 30 mA 23 IDD4R 105 95 mA 23, 48 IDD4W 105 95 mA 23 IDD5 IDD5A IDD6 IDD6A IDD7 115 6 4 2 175 105 6 4 2 175 mA mA mA mA mA 50 28, 50 12 12 23, 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 Electrical Specifications – DC and AC Electrical Specifications – DC and AC Stresses greater than those listed in Table 1 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 1: Absolute Maximum Ratings Parameter Min Max Units 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 –1V –1V –1V –0.5V –55 – 3.6V 3.6V 3.6V VDDQ + 0.5V 150 50 V V V V °C mA Table 2: 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 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) High current (VOUT = Full-drive option output VDDQ - 0.373V, minimum levels (x4, x8, x16): Reduced-drive option output levels (Design Revision F and K only): Ambient operating temperatures 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 = 0.373V, maximum VREF, maximum VTT) Commercial Industrial PDF: 09005aef80768abb/Source: 09005aef82a95a3a DDR_x4x8x16_Core2.fm - 256Mb DDR: Rev. S, Core DDR: Rev. E 9/12 EN Symbol Min Max Units Notes VDD VDDQ VREF VTT VIH(DC) VIL(DC) II 2.5 2.5 0.49 × VDDQ VREF - 0.04 VREF + 0.15 –0.3 –2 2.7 2.7 0.51 × VDDQ VREF + 0.04 VDD + 0.3 VREF - 0.15 2 V V V V V V µA 37, 42 37, 42, 45 7, 45 8, 45 29 29 IOZ –5 5 µA IOH –16.8 – mA IOL 16.8 – mA IOHR –9 – mA IOLR 9 – mA TA TA 0 –40 70 85 °C °C 18 38, 40 39, 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 3: DC Electrical Characteristics and Operating Conditions (-6, -6T, -75E, -75Z, -75) Notes: 1–5 and 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 Reduced-drive option output levels (Design Revision F and K only): Ambient operating temperatures Table 4: 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 = 0.373V, maximum VREF, maximum VTT) Commercial Industrial Symbol Min Max Units Notes VDD VDDQ VREF VTT VIH(DC) VIL(DC) II 2.3 2.3 0.49 × VDDQ VREF - 0.04 VREF + 0.15 –0.3 –2 2.7 2.7 0.51 × VDDQ VREF + 0.04 VDD + 0.3 VREF - 0.15 2 V V V V V V µA 37, 42 37, 42, 45 7, 45 8, 45 29 29 IOZ –5 5 µA IOH –16.8 – mA IOL 16.8 – mA IOHR –9 – mA IOLR 9 – mA TA TA 0 –40 70 85 °C °C 38, 40 39, 40 AC Input Operating Conditions Notes: 1–5 and 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 Symbol Min Max Units Notes Input high (logic 1) voltage Input low (logic 0) voltage I/O reference voltage VIH(AC) VIL(AC) VREF(AC) VREF + 0.310 – 0.49 × VDDQ – VREF - 0.310 0.51 × VDDQ V V V 15, 29, 41 15, 29, 41 7 PDF: 09005aef80768abb/Source: 09005aef82a95a3a DDR_x4x8x16_Core2.fm - 256Mb DDR: Rev. S, Core DDR: Rev. E 9/12 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 1: Input Voltage Waveform VDDQ,min (2.3V) 1 VOH,min (1.670V 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) VIL(AC) Receiver 2 VOL,max (0.83V for SSTL_2 termination) VSSQ Transmitter Notes: 1. VOH,min with test load is 1.927V. 2. VOL,max with test load is 0.373V. 3. Numbers in diagram reflect nominal values utilizing circuit below for all devices other than -5B. VTT 25Ω 25Ω PDF: 09005aef80768abb/Source: 09005aef82a95a3a DDR_x4x8x16_Core2.fm - 256Mb DDR: Rev. S, Core DDR: Rev. E 9/12 EN Reference point 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 5: Clock Input Operating Conditions Notes: 1–5, 16, 17, and 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 Symbol Min Max Units Notes 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# VMP(DC) VIN(DC) VID(DC) VID(AC) VIX(AC) 1.15 –0.3 0.36 0.7 0.5 × VDDQ - 0.2 1.35 VDDQ + 0.3 VDDQ + 0.6 VDDQ + 0.6 0.5 × VDDQ + 0.2 V V V V V 7, 10 7 7, 9 9 10 Figure 2: SSTL_2 Clock Input Maximum clock level1 2.80V CK# X 1.45V 3 VMP(DC)2 VIX(AC) 1.25V 1.05V X VID(DC)4 VID(AC)5 CK Minimum clock level1 –0.30V 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. S, Core DDR: Rev. E 9/12 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 6: Capacitance (x4, x8 TSOP) Note: 14 applies to the entire table; Notes appear on page 35 Parameter Delta input/output capacitance: DQ[3:0] (x4), DQ[7:0] (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 Table 7: Symbol Min Max Units Notes DCIO DCI1 DCI2 CIO CI1 CI2 CI3 – – – 4.0 2.0 2.0 2.0 0.50 0.50 0.25 5.0 3.0 3.0 3.0 pF pF pF pF pF pF pF 25 30 30 Symbol Min Max Units Notes DCIO DCI1 DCI2 CIO CI1 CI2 CI3 – – – 3.5 1.5 1.5 1.5 0.50 0.50 0.25 4.5 2.5 2.5 2.5 pF pF pF pF pF pF pF 25 30 30 Symbol Min Max Units Notes DCIOL DCIOU DCI1 DCI2 CIO CI1 CI2 CI3 – – – – 4.0 2.0 2.0 2.0 0.50 0.50 0.50 0.25 5.0 3.0 3.0 3.0 pF pF pF pF pF pF pF pF 25 25 30 30 Symbol Min Max Units Notes DCIOL DCIOU DCI1 DCI2 CIO CI1 CI2 CI3 – – – – 3.5 1.5 1.5 1.5 0.50 0.50 0.50 0.25 4.5 2.5 2.5 2.5 pF pF pF pF pF pF pF pF 25 25 30 30 Capacitance (x4, x8 FBGA) Note: 14 applies to the entire table; Notes appear on page 35 Parameter 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 Table 8: Capacitance (x16 TSOP) Note: 14 applies to the entire table; Notes appear on page 35 Parameter Delta input/output capacitance: DQ[7:0], LDQS, LDM Delta input/output capacitance: DQ[15:8], 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 Table 9: Capacitance (x16 FBGA) Note: 14 applies to the entire table; Notes appear on page 35 Parameter Delta input/output capacitance: DQ[7:0], LDQS, LDM Delta input/output capacitance: DQ[15:8], 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 PDF: 09005aef80768abb/Source: 09005aef82a95a3a DDR_x4x8x16_Core2.fm - 256Mb DDR: Rev. S, Core DDR: Rev. E 9/12 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 10: Electrical Characteristics and Recommended AC Operating Conditions (-5B) Notes 1–6, 16–18, and 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 -5B Parameter Access window of DQ from CK/CK# CK high-level width Clock cycle time Symbol t AC tCH t 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 tREFI tRFC t RP t RPRE tRPST tRRD t VTD t WPRE tWPRES tWPST tWR tWTR 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 Average periodic refresh interval 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 Write recovery time Internal WRITE-to-READ command delay PDF: 09005aef80768abb/Source: 09005aef82a95a3a DDR_x4x8x16_Core2.fm - 256Mb DDR: Rev. S, Core DDR: Rev. E 9/12 EN 23 Min Max –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 15 2 0.70 0.55 7.5 13 13 0.55 – – 0.60 – – 0.40 1.28 – – – – 0.70 – – – – – – 0.50 – 70,000 – – 70.3 7.8 – – 1.1 0.6 – – – – 0.6 – – Units Notes ns tCK 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 ns ns t CK tCK ns ns t CK ns tCK ns tCK 31 52 46, 52 46, 52 31 27, 32 32 26, 27 27, 32 35 19, 43 15 15 19, 43 26, 27 36 55 24 24 50 44 44 21, 22 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 10: Electrical Characteristics and Recommended AC Operating Conditions (-5B) (continued) Notes 1–6, 16–18, and 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 -5B Parameter Symbol t Exit SELF REFRESH-to-non-READ command Exit SELF REFRESH-to-READ command Data valid output window PDF: 09005aef80768abb/Source: 09005aef82a95a3a DDR_x4x8x16_Core2.fm - 256Mb DDR: Rev. S, Core DDR: Rev. E 9/12 EN XSNR tXSRD n/a 24 Min Max 70 – 200 – t QH - tDQSQ Units Notes ns tCK ns 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 11: 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 -6 (FBGA) Parameter Access window of DQ from CK/CK# CK high-level width Clock cycle time Symbol t AC tCH t 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 tREFI t RFC t RP tRPRE tRPST tRRD t VTD tWPRE tWPRES tWPST tWR CL = 2.5 CL = 2 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 Average periodic refresh interval 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 DQS write preamble setup time DQS write postamble Write recovery time PDF: 09005aef80768abb/Source: 09005aef82a95a3a DDR_x4x8x16_Core2.fm - 256Mb DDR: Rev. S, Core DDR: Rev. E 9/12 EN 25 Min Max –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 0 0.4 15 0.70 0.55 13 13 0.55 – – 0.6 – – 0.4 1.25 – – – – 0.7 – – – – – – – – 0.50 – 70,000 – – 70.3 7.8 – – 1.1 0.6 – – – – 0.6 – Units Notes ns tCK 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 ns ns tCK tCK ns ns tCK ns tCK ns 31 46, 52 46, 52 31 27, 32 32 26, 27 27, 32 35 19, 43 15 15 19, 43 26, 27 36, 54 55 24 24 50 44 44 21, 22 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 11: 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 -6 (FBGA) Parameter Symbol t Internal WRITE-to-READ command delay Exit SELF REFRESH-to-non-READ command Exit SELF REFRESH-to-READ command Data valid output window PDF: 09005aef80768abb/Source: 09005aef82a95a3a DDR_x4x8x16_Core2.fm - 256Mb DDR: Rev. S, Core DDR: Rev. E 9/12 EN WTR tXSNR t 26 XSRD n/a Min Max 1 – 75 – 200 – tQH - tDQSQ Units Notes t CK ns t CK ns 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 12: Electrical Characteristics and Recommended AC Operating Conditions (-6T) Notes: 1–6, 16–18, and 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 -6T (TSOP) Parameter Access window of DQ from CK/CK# CK high-level width Clock cycle time Symbol t AC tCH t CK (2.5) tCK (2) t CL t DH tDIPW tDQSCK tDQSH tDQSL tDQSQ tDQSS tDS tDSH tDSS tHP CL = 2.5 CL = 2 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 t 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 Average periodic refresh interval 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 DQS write preamble setup time DQS write postamble PDF: 09005aef80768abb/Source: 09005aef82a95a3a DDR_x4x8x16_Core2.fm - 256Mb DDR: Rev. S, Core DDR: Rev. E 9/12 EN HZ tIH F tIH S tIPW tIS F tIS S tLZ tMRD tQH tQHS tRAP tRAS tRC t RCD tREFC tREFI tRFC t RP RPRE tRPST t RRD t VTD t WPRE tWPRES tWPST t 27 Min Max –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 0 0.4 0.70 0.55 13 13 0.55 – – 0.6 – – 0.45 1.25 – – – – 0.7 – – – – – – – – 0.55 – 70,000 – – 70.3 7.8 – – 1.1 0.6 – – – – 0.6 Units Notes ns tCK 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 ns ns t CK tCK ns ns t CK ns tCK 31 46, 52 46, 52 31 27, 32 32 26, 27 27, 32 35 19, 43 15 15 19, 43 26, 27 36, 54 55 24 24 50 44 44 21, 22 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 12: Electrical Characteristics and Recommended AC Operating Conditions (-6T) (continued) Notes: 1–6, 16–18, and 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 -6T (TSOP) Parameter Symbol t 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 PDF: 09005aef80768abb/Source: 09005aef82a95a3a DDR_x4x8x16_Core2.fm - 256Mb DDR: Rev. S, Core DDR: Rev. E 9/12 EN WR tWTR t XSNR tXSRD n/a 28 Min Max 15 – 1 – 75 – 200 – t QH - tDQSQ Units Notes ns tCK ns tCK ns 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 13: 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 -75E Parameter Access window of DQ from CK/CK# CK high-level width Clock cycle time Symbol t AC tCH t CK (2.5) tCK (2) t CL t DH tDIPW tDQSCK tDQSH tDQSL tDQSQ tDQSS tDS tDSH tDSS tHP CL = 2.5 CL = 2 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 t 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 Average periodic refresh interval 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 DQS write preamble setup time DQS write postamble PDF: 09005aef80768abb/Source: 09005aef82a95a3a DDR_x4x8x16_Core2.fm - 256Mb DDR: Rev. S, Core DDR: Rev. E 9/12 EN HZ tIH F tIH S tIPW tIS F tIS S tLZ tMRD tQH tQHS tRAP tRAS tRC t RCD tREFC tREFI tRFC t RP RPRE tRPST t RRD t VTD t WPRE tWPRES tWPST t 29 Min Max –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 0 0.4 0.75 0.55 13 13 0.55 – – 0.75 – – 0.5 1.25 – – – – 0.75 – – – – – – – – 0.75 – 120,000 – – 70.3 7.8 – – 1.1 0.6 – – – – 0.6 Units Notes ns tCK 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 ns ns t CK tCK ns ns t CK ns tCK 31 46, 52 46, 52 31 27, 32 32 26, 27 27, 32 35 19, 43 15 15 19, 43 26, 27 36, 54 55 24 24 50 44 44 21, 22 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: 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 -75E Parameter Symbol t 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 PDF: 09005aef80768abb/Source: 09005aef82a95a3a DDR_x4x8x16_Core2.fm - 256Mb DDR: Rev. S, Core DDR: Rev. E 9/12 EN WR tWTR t XSNR tXSRD n/a 30 Min Max 15 – 1 – 75 – 200 – t QH - tDQSQ Units Notes ns tCK ns tCK ns 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 14: 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 -75Z Parameter Access window of DQ from CK/CK# CK high-level width Clock cycle time Symbol t AC tCH t 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 tREFI t RFC t RP tRPRE tRPST tRRD t VTD tWPRE tWPRES tWPST tWR CL = 2.5 CL = 2 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 Average periodic refresh interval 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 Write recovery time PDF: 09005aef80768abb/Source: 09005aef82a95a3a DDR_x4x8x16_Core2.fm - 256Mb DDR: Rev. S, Core DDR: Rev. E 9/12 EN 31 Min Max –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 0.4 15 0.75 0.55 13 13 0.55 – – 0.75 – – 0.5 1.25 – – – – 0.75 – – – – – – – – 0.75 – 120,000 – – 70.3 7.8 – – 1.1 0.6 – – – – 0.6 – Units Notes ns tCK 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 ns ns tCK tCK ns ns tCK ns tCK ns 31 46 46 31 27, 32 32 26, 27 27, 32 35 19, 43 15 15 19, 43 26, 27 36 55 24 24 50 44 44 21, 22 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 14: 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 -75Z Parameter Symbol t Internal WRITE-to-READ command delay Exit SELF REFRESH-to-non-READ command Exit SELF REFRESH-to-READ command Data valid output window PDF: 09005aef80768abb/Source: 09005aef82a95a3a DDR_x4x8x16_Core2.fm - 256Mb DDR: Rev. S, Core DDR: Rev. E 9/12 EN WTR tXSNR t 32 XSRD n/a Min Max 1 – 75 – 200 – tQH - tDQSQ Units Notes t CK ns t CK ns 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 15: Electrical Characteristics and Recommended AC Operating Conditions (-75) Notes: 1–6, 16–18, and 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 -75 Parameter Access window of DQ from CK/CK# CK high-level width Clock cycle time Symbol t AC tCH t 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 tREFI tr FC t RP tRPRE tRPST tRRD t VTD tWPRE tWPRES tWPST tWR CL = 2.5 CL = 2 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 Average periodic refresh interval 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 Write recovery time PDF: 09005aef80768abb/Source: 09005aef82a95a3a DDR_x4x8x16_Core2.fm - 256Mb DDR: Rev. S, Core DDR: Rev. E 9/12 EN 33 Min Max –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 0.4 15 0.75 0.55 13 13 0.55 – – 0.75 – – 0.5 1.25 – – – – 0.75 – – – – – – – – 0.75 – 120,000 – – 70.3 7.8 – – 1.1 0.6 – – – – 0.6 – Units Notes ns tCK 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 ns ns tCK tCK ns ns tCK ns tCK ns 31 46 46 31 27, 32 32 26, 27 27, 32 35 19, 43 15 15 19, 43 26, 27 36 55 24 24 50 44 44 21, 22 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 15: Electrical Characteristics and Recommended AC Operating Conditions (-75) (continued) Notes: 1–6, 16–18, and 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 -75 Parameter Symbol t Internal WRITE-to-READ command delay Exit SELF REFRESH-to-non-READ command Exit SELF REFRESH-to-READ command Data valid output window Table 16: WTR tXSNR t XSRD n/a Min Max 1 – 75 – 200 – tQH - tDQSQ Units Notes t CK ns t CK ns 26 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 Slew Rate tIS tIH Units -75Z/-75E -75Z/-75E -75Z/-75E 0.500 V/ns 0.400 V/ns 0.300 V/ns 1.00 1.05 1.10 1 1 1 ns ns ns DH Units 0.50 0.55 0.60 ns ns ns Table 17: 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 Slew Rate t -75Z/-75E -75Z/-75E -75Z/-75E 0.500 V/ns 0.400 V/ns 0.300 V/ns 0.50 0.55 0.60 PDF: 09005aef80768abb/Source: 09005aef82a95a3a DDR_x4x8x16_Core2.fm - 256Mb DDR: Rev. S, Core DDR: Rev. E 9/12 EN DS 34 t 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 Output (VOUT) 50 Reference point 30pF 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. S, Core DDR: Rev. E 9/12 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 t RAS. 24. The refresh period is 64ms. This equates to an average refresh rate of 7.8125µs. However, an AUTO REFRESH command must be asserted at least once every 70.3µs; 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 3 on page 37 for duty cycles ranging between 50/50 and 45/55. 27. Referenced to each output group: x4 = DQS with DQ[3:0]; x8 = DQS with DQ[7:0]; x16 = LDQS with DQ[7:0] and UDQS with DQ[15:8]. 28. This limit is actually a nominal value and does not result in a fail value. CKE is HIGH during the REFRESH command period (tRFC [MIN]), else CKE is LOW (that is, during standby). 29. To maintain a valid level, the transitioning edge of the input must: 29a. Sustain a constant slew rate from the current AC level through to the target AC level, VIL(AC) or VIH(AC). 29b. Reach at least the target AC level. 29c. After the AC target level is reached, continue to maintain at least the target DC level, VIL(DC) or VIH(DC). PDF: 09005aef80768abb/Source: 09005aef82a95a3a DDR_x4x8x16_Core2.fm - 256Mb DDR: Rev. S, Core DDR: Rev. E 9/12 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 3: Derating Data Valid Window (tQH – tDQSQ) -6T @ tCK = 7.5ns -75E / -75 @ tCK = 7.5ns 3.0ns 2.75 Data Valid Window 2.5ns 2.50 2.10 2.71 2.46 2.07 2.68 2.43 2.04 2.0ns 2.00 1.5ns 1.60 1.97 1.58 1.94 1.55 -6 @ tCK = 6ns -6T @ tCK = 6ns 2.64 2.39 2.01 1.91 1.53 2.60 2.35 1.98 1.88 1.50 2.56 2.31 1.95 1.85 1.48 -5B @ tCK = 5ns 2.53 2.28 1.92 1.82 1.45 2.49 2.24 1.89 1.79 1.43 2.45 2.20 1.86 1.76 1.40 2.41 2.16 1.83 1.73 1.38 2.38 2.13 1.80 1.70 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 4 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 4 on page 38. PDF: 09005aef80768abb/Source: 09005aef82a95a3a DDR_x4x8x16_Core2.fm - 256Mb DDR: Rev. S, Core DDR: Rev. E 9/12 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 5 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 5 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 4: Full Drive Pull-Down Characteristics 160 140 120 IOUT (mA) 100 80 60 40 20 0 0.0 0.5 1.0 1.5 2.0 2.5 1.5 2.0 2.5 VOUT (V) Figure 5: Full Drive Pull-Up Characteristics 0 -20 -40 IOUT (mA) -60 -80 -100 -120 -140 -160 -180 -200 0.0 0.5 1.0 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 6 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 6 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 7. PDF: 09005aef80768abb/Source: 09005aef82a95a3a DDR_x4x8x16_Core2.fm - 256Mb DDR: Rev. S, Core DDR: Rev. E 9/12 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 7 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 6: Reduced Drive Pull-Down Characteristics 80 70 IOUT (mA) 60 50 40 30 20 10 0 0.0 0.5 1.0 1.5 2.0 2.5 VOUT (V) Figure 7: Reduced Drive Pull-Up Characteristics 0 -10 -20 IOUT (mA) -30 -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. S, Core DDR: Rev. E 9/12 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 42 of series resistance is used between the VTT supply and the input pin. 46. The current Micron part operates below 83 MHz (slowest specified JEDEC operating frequency). As such, future die may not reflect this option. 47. When an input signal is HIGH or LOW, it is defined as a steady state logic HIGH or LOW. 48. Random address is changing; 50% of data is changing at every transfer. 49. Random address is changing; 100% of data is changing at every transfer. 50. CKE must be active (HIGH) during the entire time a REFRESH command is executed. That is, from the time the AUTO REFRESH command is registered, CKE must be active at each rising clock edge, until tRFC has been satisfied. 51. IDD2N specifies the DQ, DQS, and DM to be driven to a valid HIGH or LOW logic level. IDD2Q is similar to IDD2F except IDD2Q specifies the address and control inputs to remain stable. Although IDD2F, IDD2N, and IDD2Q are similar, IDD2F is “worst case.” 52. Whenever the operating frequency is altered, not including jitter, the DLL is required to be reset followed by 200 clock cycles before any READ command. 53. This is the DC voltage supplied at the DRAM and is inclusive of all noise up to 20 MHz. Any noise above 20 MHz at the DRAM generated from any source other than that of the DRAM itself may not exceed the DC voltage range of 2.6V ±100mV. 54. The -6/-6T speed grades will operate with tRAS (MIN) = 40ns and t RAS (MAX) = 120,000ns at any slower frequency. 55. DRAM devices should be evenly addressed when being accessed. Disproportionate accesses to a particular row address may result in reduction of the product lifetime. PDF: 09005aef80768abb/Source: 09005aef82a95a3a DDR_x4x8x16_Core2.fm - 256Mb DDR: Rev. S, Core DDR: Rev. E 9/12 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 18: Normal Output Drive Characteristics Characteristics are specified under best, worst, and nominal process variation/conditions Pull-Down Current (mA) Pull-Up Current (mA) Voltage (V) Nominal Low Nominal High Min Max Nominal Low Nominal High Min Max 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 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 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 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 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 –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 –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 –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 –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. S, Core DDR: Rev. E 9/12 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 19: Reduced Output Drive Characteristics Characteristics are specified under best, worst, and nominal process variation/conditions Pull-Down Current (mA) Pull-Up Current (mA) Voltage (V) Nominal Low Nominal High Min Max Nominal Low Nominal High Min Max 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 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 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 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 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 –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 –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 –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 –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. S, Core DDR: Rev. E 9/12 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 20 and 21 provide a quick reference of available commands. Two additional Truth Tables—Table 22 on page 44 and Table 23 on page 45—provide current state/next state information. Table 20: Truth Table 1 – Commands CKE is HIGH for all commands shown except SELF REFRESH; All states and sequences not shown are illegal or reserved Function CS# RAS# CAS# WE# Address Notes H L L L L L L L X H L H H H L L X H H L L H H L X H H H L L L H X X Bank/row Bank/col Bank/col X Code X 1 1 2 3 3 4 5 6, 7 L L L L Op-code 8 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: Table 21: 1. DESELECT and NOP are functionally interchangeable. 2. BA[1:0] provide bank address and A[n:0] (128Mb: n = 11; 256Mb and 512Mb: n = 12; 1Gb: n = 13) provide row address. 3. BA[1:0] provide bank address; A[i:0] provide column address, (where Ai is the most 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: BA[1:0] determine which bank is precharged. A10 HIGH: all banks are precharged and BA[1:0] are “Don’t Care.” 6. This command is AUTO REFRESH if CKE is HIGH; SELF REFRESH if CKE is LOW. 7. Internal refresh counter controls row addressing while in self refresh mode, all inputs and I/Os are “Don’t Care” except for CKE. 8. BA[1:0] select either the mode register or the extended mode register (BA0 = 0, BA1 = 0 select the mode register; BA0 = 1, BA1 = 0 select extended mode register; other combinations of BA[1:0] are reserved). A[n:0] provide the op-code to be written to the selected mode register. Truth Table 2 – DM Operation Used to mask write data, provided coincident with the corresponding data Name (Function) DM DQ Write enable Write inhibit L H Valid X PDF: 09005aef80768abb/Source: 09005aef82a95a3a DDR_x4x8x16_Core2.fm - 256Mb DDR: Rev. S, Core DDR: Rev. E 9/12 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 22: 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 Row active Read (auto precharge disabled) Write (auto precharge disabled) Notes: CS# RAS# CAS# WE# H L L L L L L L L L L L L L L X H L L L H H L H H L H H H L X H H L L L L H L L H H L L H 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 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 25 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 22 and according to Table 23 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. S, Core DDR: Rev. E 9/12 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. After 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. After tMRD is met, the DDR SDRAM will be in the all banks idle state. 6. 7. 8. 9. 10. 11. 12. Table 23: • Precharging all: Starts with registration of a PRECHARGE ALL command and ends when t RP is met. After 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. Truth Table 4 – Current State Bank n – Command to Bank m Notes: 1–6 apply to the entire table; Notes appear on page 45 Current State Any Idle Row activating, active, or precharging Read (auto precharge disabled) Write (auto precharge disabled) Read (with autoprecharge) Write (with autoprecharge) Notes: CS# RAS# CAS# WE# H L X L L L L L L L L L L L L L L L L L L L L X H X L H H L L H H L L H H L L H H L L H H L X H X H L L H H L L H H L L H H L L H H L L H 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 7 7 7 7, 9 7, 8 7 7 7, 9 7 7 1. This table applies when CKEn-1 was HIGH and CKEn is HIGH (see Table 25 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. S, Core DDR: Rev. E 9/12 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 24. Table 24: Command Delays CLRU = CL rounded up to the next integer From Command WRITE with auto precharge READ with auto precharge To Command Minimum Delay with Concurrent Auto Precharge 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 [1 + (BL/2)] × tCK + tWTR (BL/2) × tCK 1 tCK 1 tCK (BL/2) × tCK [CLRU + (BL/2)] × tCK 1 tCK 1 tCK 4. AUTO REFRESH and LMR commands may only be issued when all banks are idle. 5. A BURST TERMINATE command cannot be issued to another bank; it applies to the bank represented by the current state only. 6. All states and sequences not shown are illegal or reserved. 7. READs or WRITEs listed in the “Command/Action” column include READs or WRITEs with auto precharge enabled and READs or WRITEs with auto precharge disabled. 8. Requires appropriate DM masking. 9. A WRITE command may be applied after the completion of the READ burst; otherwise, a BURST TERMINATE must be used to end the READ burst prior to asserting a WRITE command. PDF: 09005aef80768abb/Source: 09005aef82a95a3a DDR_x4x8x16_Core2.fm - 256Mb DDR: Rev. S, Core DDR: Rev. E 9/12 EN 46 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 25: Truth Table 5 – CKE Notes 1–6 apply to the entire table; Notes appear below CKEn-1 CKEn Current State Commandn Actionn Notes L L L H Power-down Self refresh Power-down Self refresh All banks idle Bank(s) active All banks idle X X DESELECT or NOP DESELECT or NOP DESELECT or NOP DESELECT or NOP AUTO REFRESH See Table 20 on page 43 Maintain power-down Maintain self refresh Exit power-down Exit self refresh Precharge power-down entry Active power-down entry Self refresh entry 7 H L H H Notes: 1. CKEn is the logic state of CKE at clock edge n; CKEn-1 was the state of CKE at the previous clock edge. 2. Current state is the state of the DDR SDRAM immediately prior to clock edge n. 3. COMMANDn is the command registered at clock edge n, and ACTIONn is a result of 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. S, Core DDR: Rev. E 9/12 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 8. The value on the BA0, BA1 inputs selects the bank, and the address provided on inputs A[n:0] selects the row. Figure 8: Activating a Specific Row in a Specific Bank CK# CK CKE HIGH CS# RAS# CAS# WE# Address BA0, BA1 Row Bank Don’t Care PDF: 09005aef80768abb/Source: 09005aef82a95a3a DDR_x4x8x16_Core2.fm - 256Mb DDR: Rev. S, Core DDR: Rev. E 9/12 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 9 on page 49. The value on the BA0, BA1 inputs selects the bank, and the address provided on inputs A[i:0] (where Ai is the most significant column address bit for a given density and configuration, see Table 2 on page 2) selects the starting column location. Figure 9: READ Command CK# CK CKE HIGH CS# RAS# CAS# WE# Address Col EN AP A10 DIS AP BA0, BA1 Bank Don’t Care Note: EN AP = enable auto precharge; DIS AP = disable auto precharge. PDF: 09005aef80768abb/Source: 09005aef82a95a3a DDR_x4x8x16_Core2.fm - 256Mb DDR: Rev. S, Core DDR: Rev. E 9/12 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 10. The value on the BA0, BA1 inputs selects the bank, and the address provided on inputs A[i:0] (where Ai is the most significant column address bit for a given density and configuration, see Table 2 on page 2) selects the starting column location. Figure 10: 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. S, Core DDR: Rev. E 9/12 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 11. 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 11: PRECHARGE Command CK# CK CKE HIGH CS# RAS# CAS# WE# Address All banks A10 One bank BA0, BA1 Bank1 Don’t Care Notes: 1. If A10 is HIGH, bank address becomes “Don’t Care.” BURST TERMINATE (BST) The BURST TERMINATE command is used to truncate READ bursts (with auto precharge disabled). The most recently registered READ command prior to the BURST TERMINATE command will be truncated, as shown in “Operations” on page 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). PDF: 09005aef80768abb/Source: 09005aef82a95a3a DDR_x4x8x16_Core2.fm - 256Mb DDR: Rev. S, Core DDR: Rev. E 9/12 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. S, Core DDR: Rev. E 9/12 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 12: 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. S, Core DDR: Rev. E 9/12 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 13: INITIALIZATION Timing Diagram (( )) VDD VDDQ (( )) tVTD1 VTT1 (( )) VREF (( )) CK# (( )) (( )) T1 T0 CK tIS CKE LVCMOS LOW level ( ( )) Command (( )) (( )) tCH tIH tCL tIS tIH NOP PRE tCK Ta0 Tb0 Tc0 Td0 Te0 Tf0 (( )) (( )) (( )) (( )) (( )) (( )) (( )) (( )) (( )) (( )) (( )) (( )) (( )) (( )) (( )) (( )) (( )) (( )) (( )) (( )) (( )) (( )) (( )) (( )) (( )) (( )) DM (( )) (( )) (( )) (( )) Address (( )) (( )) (( )) (( )) A10 (( )) (( )) All banks ( ( )) (( ) tIS tIH ) BA0, BA1 (( )) (( )) (( )) (( )) DQS (( )) High-Z (( )) DQ (( )) High-Z (( )) LMR (( )) (( )) LMR (( )) (( )) (( )) (( )) PRE (( )) (( )) AR (( )) (( )) AR (( )) (( )) (( )) (( )) (( )) (( )) (( )) (( )) (( )) (( )) ACT2 tIS tIH Code (( )) (( )) Code3 (( )) (( )) (( )) (( )) (( )) (( )) (( )) (( )) RA (( )) (( )) Code ( ( All banks )) (( )) tIS tIH (( )) (( )) (( )) (( )) (( )) (( )) RA (( )) (( )) BA0 = 0 BA1 = 0 (( )) (( )) (( )) (( )) (( )) (( )) (( )) (( )) BA (( )) (( )) (( )) (( )) (( )) (( )) (( )) (( )) (( )) (( )) tRP tRFC tRFC tIS tIH Code tIS tIH BA0 = 1 BA1 = 0 T = 200µs Power-up: VDD and CK stable Notes: tRP tMRD tMRD Load extended mode register Load mode register5 200 cycles of CK4 Indicates A Break in Time Scale Don’t Care 1. VTT is not applied directly to the device; however, tVTD 0 to avoid device latch-up. VDDQ, VTT, and VREF VDD + 0.3V. Alternatively, VTT may be 1.35V maximum during power-up, even if VDD/VDDQ are 0V, provided a minimum of 42of series resistance is used between the VTT supply and the input pin. Once initialized, VREF must always be powered within the specified range. 2. Although not required by the Micron device, JEDEC specifies issuing another LMR command (A8 = 0) prior to activating any bank. If another LMR command is issued, the same, 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. S, Core DDR: Rev. E 9/12 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 14. 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 A[2:0] specify the burst length, A3 specifies the type of burst (sequential or interleaved), A[6:4] specify the CAS latency, and A[n:7] specify the operating mode. Figure 14: Mode Register Definition BA1 BA0 An . . . n + 2 n + 1 n1 . . . 0 A9 A8 A7 A6 A5 A4 A3 A2 A1 A0 Address bus 9 8 7 Operating mode 0 6 5 4 3 2 1 0 Mode register (Mx) CAS Latency BT Burst length M2 M1 M0 Burst Length Mn + 2 Mn + 1 Mode Register Definition 0 0 Base mode register 0 1 Extended mode register 1 0 1 1 M3 Burst Type Reserved 0 Sequential Reserved 1 Interleaved Mn . . . M9 M8 M7 M6–M0 Operating Mode Notes: 0 0 0 0 0 Valid Normal operation 0 0 0 1 0 Valid Normal operation/reset DLL – – – – – – All other states reserved 0 0 0 Reserved 0 0 1 2 0 1 0 4 0 1 1 8 1 0 0 Reserved 1 0 1 Reserved 1 1 0 Reserved 1 1 1 Reserved M6 M5 M4 CAS Latency 0 0 0 Reserved 0 0 1 Reserved 0 1 0 2 0 1 1 3 (-5B only) 1 0 0 Reserved 1 0 1 Reserved 1 1 0 2.5 1 1 1 Reserved 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. S, Core DDR: Rev. E 9/12 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 14 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 A[i:1] when BL = 2, by A[i:2] when BL = 4, and by A[i:3] when BL = 8 (where Ai is the most significant column address bit for a given configuration). The remaining (least significant) address bit(s) is (are) used to select the starting location within the block. For example: for BL = 8, A[i:3]select the eight-data-element block; A[2:0] select the first access within the block. Burst Type Accesses within a given burst may be programmed to be either sequential or interleaved; this is referred to as the burst type and is selected via bit M3. The ordering of accesses within a burst is determined by the burst length, the burst type, and the starting column address, as shown in Table 26. Table 26: Burst Definition Order of Accesses Within a Burst Burst Length 2 4 8 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 PDF: 09005aef80768abb/Source: 09005aef82a95a3a DDR_x4x8x16_Core2.fm - 256Mb DDR: Rev. S, Core DDR: Rev. E 9/12 EN A0 0 1 A0 0 1 0 1 A0 0 1 0 1 0 1 0 1 Type = Sequential Type = Interleaved – 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 – 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 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 15. 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 27 on page 58 indicates the operating frequencies at which each CL setting can be used. Figure 15: CAS Latency T0 T1 T2 READ NOP NOP T2n T3 T3n CK# CK Command NOP CL = 2 DQS DQ T0 T1 T2 T2n T3 READ NOP NOP NOP T3n CK# CK Command CL = 2.5 DQS DQ T0 T1 T2 T3 READ NOP NOP NOP T3n CK# CK Command CL = 3 DQS DQ Transitioning Data Note: Don’t Care BL = 4 in the cases shown; shown with nominal tAC, tDQSCK, and tDQSQ. PDF: 09005aef80768abb/Source: 09005aef82a95a3a DDR_x4x8x16_Core2.fm - 256Mb DDR: Rev. S, Core DDR: Rev. E 9/12 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 27: CAS Latency Allowable Operating Clock Frequency (MHz) Speed CL = 2 CL = 2.5 CL = 3 -5B 75 f 133 75 f 167 133 f 200 -6/-6T 75 f 133 75 f 167 – -75E 75 f 133 75 f 133 – -75Z 75 f 133 75 f 133 – -75 75 f 100 75 f 133 – Operating Mode The normal operating mode is selected by issuing an LMR command with bits A7–An each set to zero and bits A[6:0] set to the desired values. A DLL reset is initiated by issuing an LMR command with bits A7 and A[n:9] each set to zero, bit A8 set to one, and bits A[6:0] set to the desired values. Although not required by the Micron device, JEDEC specifications recommend that an LMR command resetting the DLL should always be followed by an LMR command selecting normal operating mode. All other combinations of values for A[n:7] are reserved for future use and/or test modes. Test modes and reserved states should not be used, as unknown operation or 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 16 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. S, Core DDR: Rev. E 9/12 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 16: Extended Mode Register Definition BA1 BA0 An . . . A9 A8 A7 A6 A5 A4 A3 A2 A1 A0 n + 2 n + 1 n1 . . . 9 8 7 6 5 Operating Mode 0 1 Mn + 2 Mn + 1 3 Mode Register Definition 2 1 0 DS DLL DLL 0 Enable 1 Disable 0 Base mode register 0 1 Extended mode register E1 1 0 Reserved 0 Normal 1 1 Reserved 1 Reduced 2 Extended mode register (Ex) E0 0 En . . . E9 E8 E7 E6 E5 E4 E3 E2 Notes: 4 Address bus Drive Strength E1, E0 Operating Mode 0 0 0 0 0 0 0 0 0 0 Valid Reserved – – – – – – – – – – – Reserved 1. n is the most significant row address bit from Table 2 on page 2. 2. The QFC# option is not supported. ACTIVE After a row is opened with an ACTIVE command, a READ or WRITE command may be issued to that row, subject to the tRCD specification. tRCD (MIN) should be divided by the clock period and rounded up to the next whole number to determine the earliest clock edge after the ACTIVE command on which a READ or WRITE command can be entered. For example, a tRCD specification of 20ns with a 133 MHz clock (7.5ns period) results in 2.7 clocks rounded to 3. This is reflected in Figure 17 on page 60, which covers any case where 2 < tRCD (MIN)/tCK 3 (Figure 17 also shows the same case for tRRD; the same procedure is used to convert other specification limits from time units to clock cycles). A row remains active (or open) for accesses until a PRECHARGE command is issued to that bank. A PRECHARGE command must be issued before opening a different row in the same bank. A subsequent ACTIVE command to a different row in the same bank can only be issued after the previous active row has been “closed” (precharged). The minimum time interval between successive ACTIVE commands to the same bank is defined by tRC. A subsequent ACTIVE command to another bank can be issued while the first bank is being accessed, which results in a reduction of total row-access overhead. The minimum time interval between successive ACTIVE commands to different banks is defined by t RRD. PDF: 09005aef80768abb/Source: 09005aef82a95a3a DDR_x4x8x16_Core2.fm - 256Mb DDR: Rev. S, Core DDR: Rev. E 9/12 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 17: Example: Meeting tRCD (tRRD) MIN When 2 < tRCD (tRRD) MIN/tCK 3 T0 T1 T2 NOP NOP T3 T4 T5 T6 T7 NOP NOP RD/WR NOP CK# CK Command ACT Address Row Row Col Bank x Bank y Bank y BA0, BA1 ACT tRCD tRRD 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 18 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 26 on page 70 and Figure 27 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 28 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 19 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 20 on page 64. Full-speed random read accesses within a page (or pages) can be performed, as shown in Figure 21 on page 65. PDF: 09005aef80768abb/Source: 09005aef82a95a3a DDR_x4x8x16_Core2.fm - 256Mb DDR: Rev. S, Core DDR: Rev. E 9/12 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 22 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 23 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 24 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. S, Core DDR: Rev. E 9/12 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 18: READ Burst CK# T0 T1 T2 READ NOP NOP T2n T3 T3n T4 T5 NOP NOP T4 T5 NOP NOP CK Command Address NOP Bank a, Col n CL = 2 DQS DO n DQ T0 T1 T2 Command READ NOP NOP Address Bank a, Col n T2n T3 T3n CK# CK NOP CL = 2.5 DQS DO n DQ T0 T1 T2 T3 Command READ NOP NOP NOP Address Bank a, Col n T3n T4 T4n T5 CK# CK NOP NOP CL = 3 DQS DO n DQ Transitioning Data Notes: 1. 2. 3. 4. Don’t Care 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. S, Core DDR: Rev. E 9/12 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 19: Consecutive READ Bursts T0 T1 T2 Command READ NOP READ Address Bank, Col n CK# T2n T3 T3n T4 T4n T5 T5n CK NOP NOP NOP Bank, Col b CL = 2 DQS DO n DQ T0 T1 T2 Command READ NOP READ Address Bank, Col n CK# DO b T2n T3 T3n T4 T4n T5 T5n CK NOP NOP NOP Bank, Col b CL = 2.5 DQS DO n DQ DO b T0 T1 T2 T3 Command READ NOP READ NOP Address Bank, Col n T3n T4 T4n T5 T5n CK# CK NOP NOP Bank, Col b CL = 3 DQS DO n DQ DO b Transitioning Data Notes: Don’t Care 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. S, Core DDR: Rev. E 9/12 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 20: Nonconsecutive READ Bursts T0 T1 T2 Command READ NOP NOP Address Bank, Col n T2n T3 T3n T4 T5 NOP NOP T5n T6 CK# CK READ NOP Bank, Col b CL = 2 DQS DO n DQ T0 T1 T2 Command READ NOP NOP Address Bank, Col n DO b T2n T3 T3n T4 T5 NOP NOP T5n T6 CK# CK READ NOP Bank, Col b CL = 2.5 DQS DO n DQ DO b T0 T1 T2 T3 T3n Command READ NOP NOP READ Address Bank, Col n T4n T4 T5 T6 NOP NOP CK# CK NOP Bank, Col b CL = 3 DQS DO n DQ DO b Transitioning Data Notes: Don’t Care 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. S, Core DDR: Rev. E 9/12 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 21: Random READ Accesses T0 T1 Command READ READ READ Address Bank, Col n Bank, Col x Bank, Col b CK# T2 T2n T3 T3n T4 T4n T5 T5n CK READ NOP NOP Bank, Col g CL = 2 DQS DO n DQ DO n' T2n DO x T0 T1 T2 T3 Command READ READ READ READ Address Bank, Col n Bank, Col x Bank, Col b Bank, Col g DO x' T3n DO b T4 DO b' T4n DO g T5 T5n CK# CK NOP NOP CL = 2.5 DQS DO n DQ DO n' T0 T1 T2 T3 Command READ READ READ READ Address Bank, Col n Bank, Col x Bank, Col b Bank, Col g CK# DO x T3n DO x' T4 DO b T4n DO b' T5 T5n CK NOP NOP CL = 3 DQS DO n DQ DO n' DO x Transitioning Data Notes: 1. 2. 3. 4. 5. DO x' DO b DO b' Don’t Care 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. S, Core DDR: Rev. E 9/12 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 22: Terminating a READ Burst T0 T1 T2 READ BST1 NOP T2n T3 T4 T5 NOP NOP NOP T3 T4 T5 NOP NOP NOP T4 T5 NOP NOP CK# CK Command Address Bank a, Col n CL = 2 DQS DO n DQ T0 T1 T2 READ BST1 NOP T2n CK# CK Command Address Bank a, Col n CL = 2.5 DQS DO n DQ T0 T1 T2 T3 READ BST1 NOP NOP T3n CK# CK Command Address Bank a, Col n CL = 3 DQS DO n DQ Transitioning Data Notes: 1. 2. 3. 4. 5. Don’t Care 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. S, Core DDR: Rev. E 9/12 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 23: READ-to-WRITE T0 T1 T2 Command READ 1 BST NOP Address Bank, Col n T2n T3 T4 T4n T5 T5n CK# CK WRITE NOP NOP Bank, Col b tDQSS (NOM) CL = 2 DQS DO n DQ DI b DM T0 T1 T2 Command READ 1 BST NOP Address Bank, Col n T2n T3n T3 T4 T5 T5n CK# CK NOP WRITE NOP Bank, Col b tDQSS (NOM) CL = 2.5 DQS DO n DQ DI b DM T0 T1 T2 T3 READ BST1 NOP NOP T3n T4 T5 T5n CK# CK Command Address WRITE NOP Bank a, Col n tDQSS (NOM) CL = 3 DQS DO n DQ DI b DM Transitioning Data Notes: 1. 2. 3. 4. 5. 6. Don’t Care 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. S, Core DDR: Rev. E 9/12 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 24: READ-to-PRECHARGE T0 T1 T2 READ NOP PRE T2n T3 T3n T4 T5 NOP ACT CK# CK Command Address Bank a, Col n NOP Bank a, (a or all) Bank a, Row tRP CL = 2 DQS DO n DQ T0 T1 T2 READ NOP PRE T2n T3 T3n T4 T5 NOP ACT CK# CK Command Address NOP Bank a, (a or all) Bank a, Col n Bank a, Row tRP CL = 2.5 DQS DO n DQ T0 T1 READ NOP T2 T3 PRE NOP T3n T4 T4n T5 CK# CK Command Address NOP Bank a, (a or all) Bank a, Col n ACT Bank a, Row tRP CL = 3 DQS DO n DQ Transitioning Data Notes: Don’t Care 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. S, Core DDR: Rev. E 9/12 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 25: CK# Bank READ – Without Auto Precharge T1 T0 T2 T3 T4 T5 T5n T6 T6n T7 T8 CK tIS tIH tIS tIH tCK tCH tCL CKE Command 1 NOP 1 ACT tIS NOP tIS A10 NOP 1 3 1 NOP PRE 1 NOP Col n Row Address 2 READ ACT tIH Row tIH All banks 4 Row Row One bank tIS BA0, BA1 tIH Bank x Bank x tRCD Bank x 5 Bank x CL = 2 tRAS3 tRP tRC DM Case 1: tAC (MIN) and tDQSCK (MIN) tRPRE tDQSCK (MIN) tRPST DQS tLZ (MIN) DO n DQ tLZ (MIN) Case 2: tAC (MAX) and tDQSCK (MAX) tRPRE tAC (MIN) tDQSCK (MAX) tRPST DQS DO n DQ tAC (MAX) tHZ (MAX) Transitioning Data Notes: Don’t Care 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 26 on page 70, Figure 27 on page 71, and Figure 28 on page 72 for detailed DQS and DQ timing. PDF: 09005aef80768abb/Source: 09005aef82a95a3a DDR_x4x8x16_Core2.fm - 256Mb DDR: Rev. S, Core DDR: Rev. E 9/12 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 26: x4, x8 Data Output Timing – tDQSQ, tQH, and Data Valid Window T1 T2 T2n T3 T3n T4 CK# CK tHP1 tHP1 tHP1 tHP1 tDQSQ2 tDQSQ2 tHP1 tHP1 tDQSQ2 tDQSQ2 tQH5 tQH5 3 DQS DQ (last data valid) DQ4 DQ4 DQ4 DQ4 DQ4 DQ4 DQ (first data no longer valid) tQH5 tQH5 DQ (last data valid) T2 T2n T3 T3n DQ (first data no longer valid) T2 T2n T3 T3n 6 All DQ and DQS collectively T2 T2n T3 T3n Data valid window Data valid window Data valid window Earliest signal transition Latest signal transition Notes: 1. 2. 3. 4. 5. 6. Data valid window 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. S, Core DDR: Rev. E 9/12 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 27: x16 Data Output Timing – tDQSQ, tQH, and Data Valid Window T1 T2 T2n T3 T3n T4 CK# CK tHP1 tHP1 tHP1 tHP1 tDQSQ2 tDQSQ2 tQH5 tQH5 tHP1 tHP1 tDQSQ2 tDQSQ2 tQH5 tQH5 LDQS3 DQ (last data valid) 4 DQ (last data valid) DQ (first data no longer valid) DQ0–DQ7 and LDQS collectively 4 4 6 Lower byte 4 DQ 4 DQ 4 DQ 4 DQ 4 DQ 4 DQ 4 DQ (first data no longer valid) T2 T2n T3 T3n T2 T2n T3 T3n T2 T2n T3 T3n Data valid window Data valid window Data valid window UDQS DQ (last data valid) Data valid window tDQSQ2 tDQSQ2 tDQSQ2 tDQSQ2 tQH5 tQH5 tQH5 tQH5 3 7 DQ (last data valid) DQ (first data no longer valid) DQ8–DQ15 and UDQS collectively 7 7 6 Upper byte 7 DQ 7 DQ 7 DQ 7 DQ 7 DQ 7 DQ 7 DQ (first data no longer valid) T2 T2n T2 T2n T2 T2n Data valid window Notes: 1. 2. 3. 4. 5. 6. 7. Data valid window T3 T3 T3 Data valid window T3n T3n T3n Data valid window 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. S, Core DDR: Rev. E 9/12 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 28: Data Output Timing – tAC and tDQSCK CK# T01 T1 T2 T3 T2n T3n T4 T4n CK T5n tRPST tRPRE DQS or LDQS/UDQS3 DQ (last data valid) T6 t tDQSCK2 (MAX) HZ (MAX) tDQSCK2 (MIN) tDQSCK2 (MAX) tDQSCK2 (MIN) tLZ (MIN) T5 T2 T2n T3 T3n T4 T4n T5 T5n DQ (first data valid) T2 T2n T3 T3n T4 T4n T5 T5n All DQ values collectively4 T2 T2n T3 T3n T4 T4n T5 T5n tLZ (MIN) Notes: tAC5 (MIN) tAC5 (MAX) tHZ (MAX) 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 29 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. S, Core DDR: Rev. E 9/12 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 30 on page 75 shows concatenated bursts of 4. An example of nonconsecutive WRITEs is shown in Figure 31 on page 76. Full-speed random write accesses within a page or pages can be performed as shown in Figure 32 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 33 on page 77. Data for any WRITE burst may be truncated by a subsequent READ command, as shown in Figure 34 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 35 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 36 on page 80. Data for any WRITE burst may be truncated by a subsequent PRECHARGE command, as shown in Figure 37 on page 81 and Figure 38 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 37 and 38. 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. S, Core DDR: Rev. E 9/12 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 29: WRITE Burst T0 T1 T2 Command WRITE NOP NOP Address Bank a, Col b T2n T3 CK# CK NOP tDQSS (NOM) DQS tDQSS DI b DQ DM tDQSS (MIN) DQS DQ tDQSS DI b DM tDQSS (MAX) DQS tDQSS DI b DQ DM Transitioning Data Notes: 1. 2. 3. 4. Don’t Care 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. S, Core DDR: Rev. E 9/12 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 30: Consecutive WRITE-to-WRITE T0 T1 Command WRITE NOP Address Bank, Col b T1n T2 T2n T3 T3n T4 T4n T5 CK# CK tDQSS (NOM) WRITE NOP NOP NOP Bank, Col n tDQSS DQS DI b DQ DI n DM Transitioning Data Notes: 1. 2. 3. 4. 5. Don’t Care 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. S, Core DDR: Rev. E 9/12 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 31: Nonconsecutive WRITE-to-WRITE T0 T1 Command WRITE NOP Address Bank, Col b T1n T2 T2n T3 T4 T4n T5 T5n CK# CK NOP WRITE NOP NOP Bank, Col n tDQSS tDQSS (NOM) DQS DI n DI b DQ DM Transitioning Data Notes: Figure 32: 1. 2. 3. 4. 5. Don’t Care 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. Random WRITE Cycles T0 T1 T1n T2 T2n T3 T3n T4 Command WRITE WRITE WRITE WRITE WRITE Address Bank, Col b Bank, Col x Bank, Col n Bank, Col a Bank, Col g T4n T5 T5n CK# CK NOP tDQSS (NOM) DQS DI b DQ DI b' DI x DI x' DI n DI n' DI a DI a' DI g DI g' DM Transitioning Data Notes: Don’t Care 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. PDF: 09005aef80768abb/Source: 09005aef82a95a3a DDR_x4x8x16_Core2.fm - 256Mb DDR: Rev. S, Core DDR: Rev. E 9/12 EN 76 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: WRITE-to-READ – Uninterrupting T0 T1 WRITE NOP T1n T2 T2n T3 T4 T5 T6 T6n READ NOP NOP CK# CK Command NOP NOP tWTR Bank a, Col b Address tDQSS (NOM) Bank a, Col n tDQSS CL = 2 DQS DI b DQ DO n DM tDQSS (MIN) tDQSS CL = 2 DQS DI b DQ DO n DM tDQSS (MAX) tDQSS CL = 2 DQS DI b DQ DO n DM Transitioning Data Notes: Don’t Care 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. S, Core DDR: Rev. E 9/12 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 34: WRITE-to-READ – Interrupting T0 T1 WRITE NOP T1n T2 T2n T3 T3n T4 T5 NOP NOP T5n T6 T6n CK# CK Command NOP READ NOP tWTR Bank a, Col b Address tDQSS (NOM) Bank a, Col n tDQSS CL = 2 DQS DI b DQ DO n DM tDQSS (MIN) tDQSS CL = 2 DQS DI b DQ DO n DM tDQSS (MAX) tDQSS CL = 2 DQS DI b DQ DO n DM Transitioning Data Notes: 1. 2. 3. 4. 5. 6. 7. Don’t Care 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. S, Core DDR: Rev. E 9/12 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 35: WRITE-to-READ – Odd Number of Data, Interrupting T0 T1 WRITE NOP T1n T2 T2n T3 T3n T4 T5 NOP NOP T5n T6 T6n CK# CK Command NOP READ NOP tWTR Address tDQSS (NOM) Bank a, Col b Bank a, Col n tDQSS CL = 2 DQS DI b DQ DO n DM tDQSS (MIN) tDQSS CL = 2 DQS DI b DQ DO n DM tDQSS (MAX) tDQSS CL = 2 DQS DI b DQ DO n DM Transitioning Data Notes: Don’t Care 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. S, Core DDR: Rev. E 9/12 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 36: WRITE-to-PRECHARGE – Uninterrupting T0 T1 WRITE NOP T1n T2 T2n T3 T4 T5 NOP PRE T6 CK# CK Command NOP NOP tWR Address tDQSS (NOM) NOP tRP Bank, (a or all) Bank a, Col b tDQSS DQS DI b DQ DM tDQSS (MIN) tDQSS DQS DI b DQ DM tDQSS (MAX) tDQSS DQS DI b DQ DM Transitioning Data Notes: Don’t Care 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. S, Core DDR: Rev. E 9/12 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 37: WRITE-to-PRECHARGE – Interrupting T0 T1 WRITE NOP T1n T2 T2n T3 T3n T4 T4n T5 T6 CK# CK Command NOP NOP PRE Address tDQSS (NOM) NOP NOP tRP tWR Bank, (a or all) Bank a, Col b tDQSS DQS DI b DQ DM tDQSS (MIN) tDQSS DQS DI b DQ DM tDQSS (MAX) tDQSS DQS DI b DQ DM Transitioning Data Notes: 1. 2. 3. 4. 5. 6. 7. Don’t Care 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. S, Core DDR: Rev. E 9/12 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 38: WRITE-to-PRECHARGE – Odd Number of Data, Interrupting T0 T1 WRITE NOP T1n T2 T2n T3 T3n T4 T4n T5 T6 CK# CK Command NOP NOP PRE Address tDQSS (NOM) NOP NOP tRP tWR Bank, (a or all) Bank a, Col b tDQSS DQS DI b DQ DM tDQSS (MIN) tDQSS DQS DI b DQ DM tDQSS (MAX) tDQSS DQS DI b DQ DM Transitioning Data Notes: 1. 2. 3. 4. 5. 6. Don’t Care 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. S, Core DDR: Rev. E 9/12 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 39: Bank WRITE – Without Auto Precharge T1 T0 CK# T2 T3 T4 WRITE2 NOP1 T4n T5 T5n T6 T7 T8 NOP1 NOP1 PRE CK tIS tIH tIS tIH tCK tCH tCL CKE Command NOP1 NOP1 ACT tIS tIH Row Address Col n tIS A10 BA0, BA1 tIH All banks 3 Row tIS NOP1 One bank tIH Bank x Bank x4 Bank x tWR tRCD tRP tRAS tDQSS (NOM) DQS tDQSL tWPRES tWPRE tDQSH tWPST DI b DQ5 DM tDS tDH Transitioning Data Notes: Don’t Care 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 41 on page 85 for detailed DQ timing. PDF: 09005aef80768abb/Source: 09005aef82a95a3a DDR_x4x8x16_Core2.fm - 256Mb DDR: Rev. S, Core DDR: Rev. E 9/12 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 40: WRITE – DM Operation T1 T0 T2 T3 T4 T4n T5 T5n T6 T7 T8 CK# CK tIS tIH tIS tIH tCK tCH tCL CKE Command 1 NOP 1 NOP ACT tIS BA0, BA1 1 NOP PRE tIH All banks 3 Row tIS 1 NOP Col n tIS A10 1 NOP tIH Row Address 1 NOP 2 WRITE One bank tIH Bank x 4 Bank x Bank x tWR tRCD tRP tRAS tDQSS (NOM) DQS tDQSL tWPRES tWPRE DQ 5 tDQSH tWPST DI b DM tDS tDH Transitioning Data Notes: Don’t Care 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 41 on page 85 for detailed DQ timing. PDF: 09005aef80768abb/Source: 09005aef82a95a3a DDR_x4x8x16_Core2.fm - 256Mb DDR: Rev. S, Core DDR: Rev. E 9/12 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 41: Data Input Timing 1 T0 T1 T1n T2 T2n T3 CK# CK tDQSS tDSH2 tDSS3 tDSH2 tDSS3 tDQSL tDQSH tWPST DQS tWPRES tWPRE DI b DQ DM tDS tDH Transitioning Data Notes: 1. 2. 3. 4. 5. Don’t Care 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. S, Core DDR: Rev. E 9/12 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 42: Bank READ – with Auto Precharge T1 T0 T2 T3 T4 2,3 READ 1 NOP T5 T5n T6 T6n T7 T8 1 NOP ACT CK# CK tIS tIH tIS tIH tCK tCH tCL CKE Command 1 ACT NOP tIS Address Row A10 Row NOP 1 1 NOP 1 NOP tIH Col n Row 4 IS BA0, BA1 tIS tIH Row IH Bank x Bank x tRCD, tRAP3 Bank x CL = 2 tRAS tRP5 tRC DM Case 1: tAC (MIN) and tDQSCK (MIN) tDQSCK (MIN) tRPRE tRPST DQS tLZ (MIN) DO n 6 DQ tLZ (MIN) tAC (MIN) Case 2: tAC (MAX) and tDQSCK (MAX) tRPRE tDQSCK (MAX) tRPST DQS DO n 6 DQ tAC (MAX) tHZ (MAX) Transitioning Data Notes: Don’t Care 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 26 on page 70, Figure 27 on page 71, and Figure 28 on page 72 for detailed DQS and DQ timing. PDF: 09005aef80768abb/Source: 09005aef82a95a3a DDR_x4x8x16_Core2.fm - 256Mb DDR: Rev. S, Core DDR: Rev. E 9/12 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 43: Bank WRITE – with Auto Precharge T1 T0 T2 T3 T4 T4n T5 T5n T6 T7 T8 1 NOP NOP CK# CK tIS tIH tIS tIH tCK tCH tCL CKE Command 1 NOP ACT tIS NOP 1 WRITE 2 1 NOP 1 NOP NOP 1 1 tIH Address Row A10 Row Col n 3 tIS BA0, BA1 tIS tIH tIH Bank x Bank x tWR tRCD tRP tRAS tDQSS (NOM) DQS tWPRES tWPRE tDQSL tDQSH tWPST DI b 4 DQ DM tDS tDH Transitioning Data Notes: Don’t Care 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 41 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. S, Core DDR: Rev. E 9/12 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 44: Auto Refresh Mode T0 T2 T1 T3 T4 CK# CK tIS tIH CKE tCL Valid tIS Command tCH CK tIH NOP1 PRE NOP1 NOP1 AR Address All banks A10 One bank tIS tIH Bank(s)4 BA0, BA1 5 DQS 5 DQ DM 5 tRP (( )) (( )) (( )) (( )) (( )) (( )) Ta0 NOP1,2 Ta1 AR3 (( )) (( )) (( )) (( )) (( )) (( )) (( )) (( )) (( )) (( )) (( )) (( )) (( )) (( )) (( )) (( )) (( )) (( )) (( )) (( )) (( )) (( )) (( )) (( )) (( )) (( )) (( )) (( )) (( )) (( )) tRFC Tb0 Tb1 Tb2 NOP1 ACT Valid NOP1,2 RA RA BA 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. S, Core DDR: Rev. E 9/12 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. Figure 45: Self Refresh Mode T11 T0 CK# CK1 tCH tIS tIH tCL tIS tIS Ta01 Ta1 Ta2 tCK t IS (( )) CKE Command2 (( )) (( )) tIH NOP (( )) (( )) AR NOP NOP Tb1 Tb2 (( )) (( )) (( )) (( )) (( )) (( )) (( )) (( )) (( )) (( )) Valid3 tIS Valid (( )) (( )) Valid Valid (( )) (( )) Valid tIH Address (( )) (( )) (( )) (( )) DQS (( )) (( )) (( )) (( )) DQ (( )) (( )) (( )) (( )) (( )) (( )) (( )) (( )) (( )) (( )) (( )) (( )) (( )) (( )) DM tRP4 Tc1 Valid tXSNR5 tXSRD6 Enter self refresh mode7 Notes: Exit self refresh mode7 Don’t Care 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. PDF: 09005aef80768abb/Source: 09005aef82a95a3a DDR_x4x8x16_Core2.fm - 256Mb DDR: Rev. S, Core DDR: Rev. E 9/12 EN 89 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 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 46 on page 91, is entered when CKE is registered LOW and all criteria in Table 25 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). 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. S, Core DDR: Rev. E 9/12 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 46: Power-Down Mode T0 T1 T2 CK# CK tCK tIS CKE tIH tCH tCL Ta0 (( )) (( )) tIS Ta1 Ta2 tIS 1 tIS Command Valid2 tIS Address (( )) tIH (( )) (( )) NOP tIH NOP (( )) (( )) Valid DQS (( )) (( )) DQ (( )) (( )) DM (( )) (( )) Valid Valid 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. S, Core DDR: Rev. E 9/12 EN 91 Micron Technology, Inc., reserves the right to change products or specifications without notice. ©2003 Micron Technology, Inc. All rights reserved.