EM68A16CBQC-25IH

EtronTech EM68A16CBQC 16M x 16 bit DDRII Synchronous DRAM (SDRAM) Advance (Rev. 1.0, May /2015) Features Overview • JEDEC Standard Compliant • JEDEC standard 1.8V I/O (SSTL_18-compatible) • Power supplies: VDD & VDDQ = +1.8V ± 0.1V • Operating temperature: -40 – 95 °C • Supports JEDEC clock jitter specification • Fully synchronous operation • Fast clock rate: 333/400/533 MHz • Differential Clock, CK & CK# • Bidirectional single/differential data strobe - DQS & DQS# 4 • internal banks for concurrent operation • 4-bit prefetch architecture • Internal pipeline architecture • Precharge & active power down • Programmable Mode & Extended Mode registers • Posted CAS# additive latency (AL): 0, 1, 2, 3, 4, 5, 6 • WRITE latency = READ latency - 1 tCK • Burst length: 4 or 8 • Burst type: Sequential / Interleave • DLL enable/disable • Off-Chip Driver (OCD) - Impedance Adjustment - Adjustable data-output drive strength • On-die termination (ODT) • RoHS compliant • Auto Refresh and Self Refresh • 8192 refresh cycles / 64ms - Average refresh period 7.8µs @ -40°C ≦TC≦ +85°C 3.9µs @ +85°C ＜TC≦ +95°C • Package: 84-ball 8 x 12.5 x 1.2mm (max) FBGA - Pb Free and Halogen Free The EM68256WQCA is a high-speed CMOS Double-Data-Rate-Two (DDR2), synchronous dynamic random-access memory (SDRAM) containing 256 Mbits in a 16-bit wide data I/Os. It is internally configured as a quad bank DRAM, 4 banks x 4Mb addresses x 16 I/Os. The device is designed to comply with DDR2 DRAM key features such as posted CAS# with additive latency, Write latency = Read latency -1, Off-Chip Driver (OCD) impedance adjustment, and On Die Termination(ODT). All of the control and address inputs are synchronized with a pair of externally supplied differential clocks. Inputs are latched at the cross point of differential clocks (CK rising and CK# falling) All I/Os are synchronized with a pair of bidirectional strobes (DQS and DQS#) in a source synchronous fashion. The address bus is used to convey row, column, and bank address information in RAS #, CAS# multiplexing style. Accesses begin with the registration of a Bank Activate command, and then it is followed by a Read or Write command. Read and write accesses to the DDR2 SDRAM are 4 or 8-bit burst oriented; accesses start at a selected location and continue for a programmed number of locations in a programmed sequence. Operating the four memory banks in an interleaved fashion allows random access operation to occur at a higher rate than is possible with standard DRAMs. An auto precharge function may be enabled to provide a self-timed row precharge that is initiated at the end of the burst sequence. A sequential and gapless data rate is possible depending on burst length, CAS latency, and speed grade of the device. Table 1. Ordering Information Part Number Clock Frequency Data Rate EM68A16CBQC-18IH 533MHz 1066Mbps/pin EM68A16CBQC-25IH 400MHz 800Mbps/pin EM68A16CBQC-3IH 333MHz 667Mbps/pin BQ: indicates 8 x 12.5 x 1.2mm FBGA Package C: indicates Generation Code I: indicates Industrial Grade H: indicates Pb Free and Halogen Free Power Supply VDD 1.8V, VDDQ 1.8V VDD 1.8V, VDDQ 1.8V VDD 1.8V, VDDQ 1.8V Package FBGA FBGA FBGA Etron Technology, Inc. No. 6, Technology Rd. V, Hsinchu Science Park, Hsinchu, Taiwan 30078, R.O.C. TEL: (886)-3-5782345 FAX: (886)-3-5778671 Etron Technology, Inc. reserves the right to change products or specification without notice. EtronTech EM68A16CBQC Table 2. Speed Grade Information Part Number Clock Frequency CAS Latency tRCD (ns) tRP (ns) EM68A16CBQC-18IH EM68A16CBQC-25IH EM68A16CBQC-3IH 533 MHz 400 MHz 333 MHz 7 5 5 13.125 12.5 15 13.125 12.5 15 Figure 1. Ball Assignment (FBGA Top View) 1 2 3 7 8 9 A VDD NC VSS VSSQ UDQS# VDDQ B DQ14 VSSQ UDM UDQS. VSSQ DQ15 C VDDQ DQ9 VDDQ VDDQ DQ8 VDDQ D DQ12 VSSQ DQ11 DQ10 VSSQ DQ13 E VDD NC VSS VSSQ LDQS# VDDQ F DQ6 VSSQ LDM LDQS VSSQ DQ7 G VDDQ DQ1 VDDQ VDDQ DQ0 VDDQ H DQ4 VSSQ DQ3 DQ2 VSSQ DQ5 J VDDL VREF VSS VSSDL CK VDD CKE WE# RAS# CK# ODT BA0 BA1 CAS# CS# A10 A1 A2 A0 A3 A5 A6 A4 A7 A9 A11 A8 A12 NC NC NC K L NC M N VSS P R VDD Rev. 1.0 2 VDD VSS May /2015 EtronTech EM68A16CBQC Figure 2. Block Diagram CK CK# DLL CLOCK BUFFER COMMAND DECODER A10/AP COLUMN COUNTER MODE REGISTER Column Decoder DATA STROBE BUFFER DQ0 4M x 16 CELL ARRAY (BANK #2) Column Decoder DQ Buffer Row Decoder ~ DQ15 ODT LDM UDM Rev. 1.0 4M x 16 CELL ARRAY (BANK #1) ADDRESS BUFFER REFRESH COUNTER LDQS LDQS# UDQS UDQS# 4M x 16 CELL ARRAY (BANK #0) Column Decoder Row Decoder A0~A9 A11 A12 BA0 BA1 CONTROL SIGNAL GENERATOR Row Decoder CS# RAS# CAS# WE# Row Decoder CKE 3 4M x 16 CELL ARRAY (BANK #3) Column Decoder May /2015 EtronTech EM68A16CBQC Figure 3. State Diagram CKEL OCD calibration Initialization Sequence SRF H CKE PR Setting MR, EMR(1) EMR(2) EMR(3) (E)MRS Idle All banks precharged ACT Self Refreshing REF CK EL CK EH Refreshing EL CK Precharge Power Down Automatic Sequence Cammand Sequence Activating Active Power Down CKEH CKE L WR Bank Active RD RD Reading W WR CKEL L CKE RA CKEL Writing WR RD A RD CKEL = CKE LOW, enter Power Down RDA A WR WRA Writing With Autoprecharge PR, PRA PR, PRA CKEH = CKE HIGH, exit Power Down,exit Self Refresh ACT = Activate RDA Reading With Autoprecharge PR, PRA WR(A) = Write (with Autoprecharge) RD(A) = Read (with Autoprecharge) PR(A) = Precharge (All) (E)MRS = (Extended) Mode Register Set SRF = Enter Self Refresh Precharging REF = Refresh Note: Use caution with this diagram. It is indented to provide a floorplan of the possible state transitions and the commands to control them, not all details. In particular situations involving more than one bank, enabling/disabling on-die termination, Power Down entry/exit, timing restrictions during state transitions, among other things, are not captured in full detail. Rev. 1.0 4 May /2015 EtronTech EM68A16CBQC Ball Descriptions Table 3. Ball Descriptions Symbol Type Description CK, CK# Input Differential Clock: CK, CK# are driven by the system clock. All SDRAM input signals are sampled on the crossing of positive edge of CK and negative edge of CK#. Output (Read) data is referenced to the crossings of CK and CK# (both directions of crossing). CKE Input Clock Enable: CKE activates (HIGH) and deactivates (LOW) the CK signal. If CKE goes LOW synchronously with clock, the internal clock is suspended from the next clock cycle and the state of output and burst address is frozen as long as the CKE remains LOW. When all banks are in the idle state, deactivating the clock controls the entry to the Power Down and Self Refresh modes. BA0, BA1 Input Bank Address: BA0 and BA1 define to which bank the BankActivate, Read, Write, or BankPrecharge command is being applied. A0-A12 Input Address Inputs: A0-A12 are sampled during the BankActivate command (row address A0-A12) and Read/Write command (column address A0-A8 with A10 defining Auto Precharge). CS# Input Chip Select: CS# enables (sampled LOW) and disables (sampled HIGH) the command decoder. All commands are masked when CS# is sampled HIGH. CS# provides for external bank selection on systems with multiple banks. It is considered part of the command code. RAS# Input Row Address Strobe: The RAS# signal defines the operation commands in conjunction with the CAS# and WE# signals and is latched at the crossing of positive edges of CK and negative edge of CK#. When RAS# and CS# are asserted "LOW" and CAS# is asserted "HIGH," either the BankActivate command or the Precharge command is selected by the WE# signal. When the WE# is asserted "HIGH," the BankActivate command is selected and the bank designated by BA is turned on to the active state. When the WE# is asserted "LOW," the Precharge command is selected and the bank designated by BA is switched to the idle state after the precharge operation. CAS# Input Column Address Strobe: The CAS# signal defines the operation commands in conjunction with the RAS# and WE# signals and is latched at the crossing of positive edges of CK and negative edge of CK#. When RAS# is held "HIGH" and CS# is asserted "LOW," the column access is started by asserting CAS# "LOW." Then, the Read or Write command is selected by asserting WE# “HIGH " or “LOW". WE# Input Write Enable: The WE# signal defines the operation commands in conjunction with the RAS# and CAS# signals and is latched at the crossing of positive edges of CK and negative edge of CK#. The WE# input is used to select the BankActivate or Precharge command and Read or Write command. LDQS, Input / LDQS# Output Bidirectional Data Strobe: Specifies timing for Input and Output data. Read Data Strobe is edge triggered. Write Data Strobe provides a setup and hold time for data and DQM. LDQS is for DQ0~7, UDQS is for DQ8~15. The data strobes LDOS and UDQS may be used in single ended mode or paired with LDQS# and UDQS# to provide differential pair signaling to the system during both reads and writes.A control bit at EMR (1)[A10] enables or disables all complementary data strobe signals. UDQS UDQS# LDM, Input UDM DQ0 - DQ15 Input / Output ODT Input Rev. 1.0 Data Input Mask: Input data is masked when DM is sampled HIGH during a write cycle. LDM masks DQ0-DQ7, UDM masks DQ8-DQ15. Data I/O: Bi-directional data bus. On Die Termination: ODT enables internal termination resistance. It is applied to each DQ, LDQS/LDQS#, UDQS/UDQS#, LDM, and UDM signal. The ODT pin is ignored if the EMR (1) is programmed to disable ODT. 5 May /2015 EtronTech EM68A16CBQC VDD Supply Power Supply: +1.8V ±0.1V VSS Supply Ground VDDL Supply DLL Power Supply: +1.8V ±0.1V VSSDL Supply DLL Ground VDDQ Supply DQ Power: +1.8V ±0.1V. VSSQ Supply DQ Ground VREF Supply Reference Voltage for Inputs: +0.5*VDDQ NC - Rev. 1.0 No Connect: These pins should be left unconnected. 6 May /2015 EtronTech EM68A16CBQC Operation Mode Table 4 shows the truth table for the operation commands. Table 4. Truth Table (Note (1), (2)) Command BankActivate State CKEn-1 CKEn DM BA0,1 A10 A0-9, 11-12 CS# RAS# CAS# WE# Row address Idle(3) H H X V Single Bank Precharge Any H H X V L All Banks Precharge Any H H X X Write Active(3) H H X Write with AutoPrecharge Active(3) H H Read Active(3) H Read and Autoprecharge Active(3) (Extended) Mode Register Set No-Operation L L H H X L L H L H X L L H L V L L H L L X V H Column address L H L L H X V L L H L H H H X V H L H L H Idle H H X V L L L L Any H X X X X X L H H H Active(4) H X X X X X L H H L Device Deselect Any H X X X X X H X X X Refresh Idle H H X X X X L L L H SelfRefresh Entry Idle H L X X X X L L L H SelfRefresh Exit Idle L H X X X X H X X X L H H H Power Down Mode Entry Idle H L X X X X H X X X L H H H Power Down Mode Exit Any L H X X X X H X X X L H H H Data Input Mask Disable Active H X L X X X X X X X X X X X Burst Stop Enable(5) (A0 – A12) (A0 - A8) Column address (A0 - A8) OP code Data Input Mask Active H X H X X X NOTE 1: V=Valid data, X=Don't Care, L=Low level, H=High level NOTE 2: CKEn signal is input level when commands are provided. NOTE 3: CKEn-1 signal is input level one clock cycle before the commands are provided. NOTE 4: These are states of bank designated by BA signal. NOTE 5: Device state is 4, and 8 burst operation. NOTE 6: LDM and UDM can be enabled respectively. Rev. 1.0 7 May /2015 EtronTech EM68A16CBQC Functional Description Read and write accesses to the DDR2 SDRAM are burst oriented; accesses start at a selected location and continue for a burst length of four or eight in a programmed sequence. Accesses begin with the registration of an Active command, which is then followed by a Read or Write command. The address bits registered coincident with the active command are used to select the bank and row to be accessed (BA0, BA1 select the bank; A0-A12 select the row). The address bits registered coincident with the Read or Write command are used to select the starting column location for the burst access and to determine if the auto precharge command is to be issued. Prior to normal operation, the DDR2 SDRAM must be initialized. The following sections provide detailed information covering device initialization, register definition, command descriptions, and device operation. z Power-up and Initialization DDR2 SDRAMs must be powered up and initialized in a predefined manner. Operational procedures other than those specified may result in undefined operation. The following sequence is required for POWER UP and Initialization. 1. Apply power and attempt to maintain CKE below 0.2*VDDQ and ODT *1 at a low state (all other inputs may be undefined.) The VDD voltage ramp time must be no greater than 200ms from when VDD ramps from 300mV to VDDmin; and during the VDD voltage ramp, |VDD-VDDQ| ≦ 0.3V - VDD, VDDL and VDDQ are driven from a single power converter output, AND - VTT is limited to 0.95 V max, AND - VREF tracks VDDQ/2. or - Apply VDD before or at the same time as VDDL. - Apply VDDL before or at the same time as VDDQ. - Apply VDDQ before or at the same time as VTT & VREF. At least one of these two sets of conditions must be met. 2. Start clock and maintain stable condition. 3. For the minimum of 200µs after stable power and clock (CK, CK#), then apply NOP or deselect and take CKE HIGH. 4. Wait minimum of 400ns then issue precharge all command. NOP or deselect applied during 400ns period. 5. Issue EMRS (2) command. (To issue EMRS (2) command, provide “LOW” to BA0, “HIGH” to BA1.) 6. Issue EMRS (3) command. (To issue EMRS (3) command, provide “HIGH” to BA0 and BA1.) 7. Issue EMRS to enable DLL. (To issue "DLL Enable" command, provide "LOW" to A0, "HIGH" to BA0 and "LOW" to BA1.) 8. Issue a Mode Register Set command for “DLL reset”. (To issue DLL reset command, provide "HIGH" to A8 and "LOW" to BA0-1) 9. Issue precharge all command. 10. Issue 2 or more auto-refresh commands. 11. Issue a mode register set command with LOW to A8 to initialize device operation. (i.e. to program operating parameters without resetting the DLL. 12. At least 200 clocks after step 8, execute OCD Calibration (Off Chip Driver impedance adjustment).If OCD calibration is not used, EMRS OCD Default command (A9=A8= A7=HIGH) followed by EMRS OCD calibration Mode Exit command (A9=A8=A7=LOW) must be issued with other operating parameters of EMRS. 13. The DDR2 SDRAM is now ready for normal operation. NOTE 1: To guarantee ODT off, VREF must be valid and a LOW level must be applied to the ODT pin. Rev. 1.0 8 May /2015 EtronTech EM68A16CBQC z Mode Register Set (MRS) The mode register stores the data for controlling the various operating modes of DDR2 SDRAM. It controls CAS latency, burst length, burst sequence, test mode, DLL reset, WR, and various vendor specific options to make DDR2 SDRAM useful for various applications.The default value of the mode register is not defined, therefore the mode register must be programmed during initialization for proper operation. The mode register is written by asserting LOW on CS#, RAS#, CAS#, WE#, BA0 and BA1, while controlling the state of address pins A0 - A12. The DDR2 SDRAM should be in all bank precharge state with CKE already HIGH prior to writing into the mode register.The mode register set command cycle time (tMRD) is required to complete the write operation to the mode register. The mode register contents can be changed using the same command and clock cycle requirements during normal operation as long as all bank are in the precharge state.The mode register is divided into various fields depending on functionality. - Burst Length Field (A2, A1, A0) This field specifies the data length of column access and selects the Burst Length. - Addressing Mode Select Field (A3) The Addressing Mode can be Interleave Mode or Sequential Mode. Both Sequential Mode and Interleave Mode support burst length of 4 and 8. - CAS Latency Field (A6, A5, A4) This field specifies the number of clock cycles from the assertion of the Read command to the first read data. The minimum whole value of CAS Latency depends on the frequency of CK. The minimum whole value satisfying the following formula must be programmed into this field. tCAC(min) ≦ CAS Latency X tCK - Test Mode field: A7; DLL Reset Mode field: A8 These two bits must be programmed to "00" in normal operation. - (BA0, BA1): Bank addresses to define MRS selection. Table 5. Mode Register Bitmap BA1 BA0 A12 0 0 A11 PD A10 A9 WR A8 DLL Reset 0 No 1 Yes A12 Active power down exit time 0 Fast exit (use tXARD) 1 Slow exit (use tXARDS) BA1 BA0 MRS Mode 0 0 MR 0 1 EMR(1) 1 0 EMR(2) 1 1 EMR(3) A7 0 1 A8 A7 DLL TM A6 A5 A4 CAS Latency Mode Normal Test A3 BT A3 0 1 Write recovery for autoprecharge*1 A11 A10 A9 WR(cycles) 0 0 0 Reserved 0 0 1 2 0 1 0 3 0 1 1 4 1 0 0 5 1 0 1 6 1 1 0 7 1 1 1 8 A2 A1 A0 Burst Length Burst Type Sequential Interleave A6 0 0 0 0 1 1 1 1 A5 0 0 1 1 0 0 1 1 A2 0 0 A4 0 1 0 1 0 1 0 1 Address Field Mode Register A1 1 1 A0 0 1 BL 4 8 CAS Latency Reserved Reserved Reserved 3 4 5 6 7 Note 1:.For DDR2-667/800/1066, WR min is determined by tCK (avg) max and WR max is determined by tCK(avg) min. WR [cycles] = RU {tWR[ns]/tCK(avg)[ns]}, where RU stands for round up. The mode register must be programmed to this value.This is also used with tRP to determine tDAL. Rev. 1.0 9 May /2015 EtronTech EM68A16CBQC z Extended Mode Register Set (EMRS) - EMR(1) The extended mode register(1) stores the data for enabling or disabling the DLL, output driver strength, ODT value selection and additive latency. The default value of the extended mode register is not defined, therefore the extended mode register must be written after power-up for proper operation. The extended mode register is written by asserting LOW on CS#, RAS#, CAS#, WE# and HIGH on BA0, while controlling the states of address pins A0 ~ A12. The DDR2 SDRAM should be in all bank precharge with CKE already HIGH prior to writing into the extended mode register. The mode register set command cycle time (tMRD) must be satisfied to complete the write operation to the extended mode register. Mode register contents can be changed using the same command and clock cycle requirements during normal operation as long as all banks are in the precharge state. A0 is used for DLL enable or disable. A1 is used for enabling a half strength data-output driver. A3~A5 determine the additive latency, A2 and A6 are used for ODT value selection, A7~A9 are used for OCD control, A10 is used for DQS# disable. - DLL Enable/Disable The DLL must be enabled for normal operation. DLL enable is required during power up initialization, and upon returning to normal operation after having the DLL disabled. The DLL is automatically disabled when entering self refresh operation and is automatically re-enabled upon exit of self refresh operation. Any time the DLL is enabled (and subsequently reset), 200 clock cycles must occur before a Read command can be issued to allow time for the internal clock to be synchronized with the external clock. Failing to wait for synchronization to occur may result in a violation of the tAC or tDQSCK parameters. Table 6. Extended Mode Register EMR (1) Bitmap BA1 BA0 A12 A11 A10 0 1 Qoff 0 A9 DQS# A8 A7 A6 OCD program Rtt Additive Latency A6 0 0 1 A2 0 1 0 Rtt(NOMINAL) ODT Disable 75Ω 1 1 50Ω BA1 BA0 MRS mode 0 0 MR 0 1 EMR(1) 1 0 EMR(2) A10 0 1 1 1 EMR(3) A9 0 0 0 1 1 A8 0 0 1 0 1 A7 0 1 0 0 1 DQS# Enable Disable A5 A4 A3 A1 OCD Calibration mode exit; maintain setting Drive(1) Drive(0) Adjust mode*1 OCD Calibration default*2 *3 Qoff Output buffer enabled Output buffer disabled A0 Address Field Rtt D.I.C DLL Extended Mode Register A0 0 1 150Ω OCD Calibration Program A12 0 1 A2 A1 0 1 A5 A4 A3 0 0 0 0 0 1 0 1 0 0 1 1 1 0 0 1 0 1 1 1 0 1 1 1 DLL Enable Enable Disable Output Driver Impedance Control Full strength Reduced strength Additive Latency 0 1 2 3 4 5 6 Reserved NOTE 1: When Adjust mode is issued, AL from previously set value must be applied. NOTE 2: After setting to default, OCD calibration mode needs to be exited by setting A9-A7 to 000. NOTE 3: Output disabled – DQs, DQSs, DQSs#.This feature is intended to be used during IDD characterization of read current. Rev. 1.0 10 May /2015 EtronTech EM68A16CBQC - EMR(2) The extended mode register (2) controls refresh related features. The default value of the extended mode register (2) is not defined, therefore the extended mode register (2) must be written after power-up for proper operation. The extended mode register(2) is written by asserting LOW on CS#, RAS#, CAS#, WE#, HIGH on BA1 and LOW on BA0, while controlling the states of address pins A0 ~ A12. The DDR2 SDRAM should be in all bank precharge with CKE already HIGH prior to writing into the extended mode register (2). The mode register set command cycle time (tMRD) must be satisfied to complete the write operation to the extended mode register (2). Mode register contents can be changed using the same command and clock cycle requirements during normal operation as long as all banks are in the precharge state. Table 7. Extended Mode Register EMR (2) Bitmap BA1 BA0 A12 A11 A10 1 0*1 0 A7 0 1 A9 A8 A7 A6 SRF A5 A4 0*1 A3 DCC*3 A2 A1 A0 Address Field 0*1 Extended Mode Register(2) High Temperature Self-Refresh Rate Enable Disable *2 Enable BA1 BA0 MRS mode 0 0 MR 0 1 EMR(1) 1 0 EMR(2) 1 1 EMR(3) A3 0 1 DCC Enable Disable Enable *3 NOTE 1: The rest bits in EMRS(2) are reserved for future use and all bits in EMRS(2) except A0-A2, A7, BA0 and BA1 must be programmed to 0 when setting the extended mode register(2) during initialization. NOTE 2: Due to the migration nature, user needs to ensure the DRAM part supports higher than 85℃ Tcase temperature self-refresh entry. If the high temperature self-refresh mode is supported then controller can set the EMRS2[A7] bit to enable the self-refresh rate in case of higher than 85℃ temperature self-refresh operation. NOTE 3: DCC (Duty Cycle Corrector) implemented, user may be given the controllability of DCC thru EMR (2) [A3] bit. Rev. 1.0 11 May /2015 EtronTech EM68A16CBQC - EMR(3) No function is defined in extended mode register(3).The default value of the extended mode register(3) is not defined, therefore the extended mode register(3) must be programmed during initialization for proper operation. Table 8. Extended Mode Register EMR (3) Bitmap BA1 BA0 A12 A11 A10 1 1 A9 A8 A7 A6 0*1 A5 A4 A3 A2 A1 A0 Address Field Extended Mode Register(3) NOTE 1: All bits in EMR (3) except BA0 and BA1 are reserved for future use and must be set to 0 when programming the EMR (3). Rev. 1.0 12 May /2015 EtronTech EM68A16CBQC z Off-chip drive (OCD) impedance adjustment DDR2 SDRAM supports driver calibration feature and the following flow chart is an example of sequence.Every calibration mode command should be followed by “OCD calibration mode exit” before any other command being issued.All MR should be programmed before entering OCD impedance adjustment and ODT (On Die Termination) should be carefully controlled depending on system environment. Figure 4. OCD impedance adjustment sequence Before entering OCD impedance adjustment, all MR should be programmed and ODT should be carefully controlled depending on system environment Start EMRS:OCD calibration mode exit EMRS:Drive(1) DQ &DQS HIGH;DQS# LOW Test EMRS:Drive(0) DQ &DQS LOW;DQS# HIGH ALL OK ALL OK Test EMRS:OCD calibration mode exit EMRS:OCD calibration mode exit EMRS:Enter Adjust Mode EMRS:Enter Adjust Mode BL=4 code input to all DQs Inc, Dec, or NOP BL=4 code input to all DQs Inc, Dec, or NOP EMRS:OCD calibration mode exit EMRS:OCD calibration mode exit EMRS:OCD calibration mode exit End Rev. 1.0 13 May /2015 EtronTech EM68A16CBQC - Extended mode register for OCD impedance adjustment OCD impedance adjustment can be done using the following EMRS mode. In drive mode all outputs are driven out by DDR2 SDRAM. In Drive (1) mode, all DQ, DQS signals are driven HIGH and all DQS# signals are driven LOW. In Drive (0) mode, all DQ, DQS signals are driven LOW and all DQS# signals are drive HIGH. In adjust mode, BL = 4 of operation code data must be used. In case of OCD calibration default, output driver characteristics have a nominal impedance value of 18 Ohms during nominal temperature and voltage conditions. Output driver characteristics for OCD calibration default are specified in the following table. OCD applies only to normal full strength output drive setting defined by EMRS and if half strength is set, OCD default driver characteristics are not applicable. When OCD calibration adjust mode is used, OCD default output driver characteristics are not applicable. After OCD calibration is completed or driver strength is set to default, subsequent EMRS commands not intended to adjust OCD characteristics must specify A7~A9 as ’000’ in order to maintain the default or calibrated value. Table 9. OCD drive mode program A9 A8 A7 operation 0 0 0 1 1 0 0 1 0 1 0 1 0 0 1 OCD calibration mode exit Drive(1) DQ, DQS, HIGH and DQS# LOW Drive(0) DQ, DQS, LOW and DQS# HIGH Adjust mode OCD calibration default - OCD impedance adjust To adjust output driver impedance, controllers must issue the ADJUST EMRS command along with a 4bit burst code to DDR2 SDRAM as in the following table. For this operation, Burst Length has to be set to BL = 4 via MRS command before activating OCD and controllers must drive this burst code to all DQs at the same time. DT0 in the following table means all DQ bits at bit time 0, DT1 at bit time 1, and so forth. The driver output impedance is adjusted for all DDR2 SDRAM DQs simultaneously and after OCD calibration, all DQs of a given DDR2 SDRAM will be adjusted to the same driver strength setting. The maximum step count for adjustment is 16 and when the limit is reached, further increment or decrement code has no effect. The default setting maybe any step within the 16 step range. When Adjust mode command is issued, AL from previously set value must be applied. Table 10. OCD adjust mode program 4bit burst code inputs to all DQs DT0 DT1 DT2 DT3 0 0 0 0 0 0 0 1 0 0 1 0 0 1 0 0 1 0 0 0 0 1 0 1 0 1 1 0 1 0 0 1 1 0 1 0 Other Combinations Rev. 1.0 Pull-up driver strength NOP Increase by 1 step Decrease by 1 step NOP NOP Increase by 1 step Decrease by 1 step Increase by 1 step Decrease by 1 step 14 Operation Pull-down driver strength NOP NOP NOP Increase by 1 step Decrease by 1 step Increase by 1 step Increase by 1 step Decrease by 1 step Decrease by 1 step Reserved May /2015 EtronTech EM68A16CBQC z ODT (On Die Termination) On Die Termination (ODT) is a feature that allows a DRAM to turn on/off termination resistance for each DQ, UDQS/UDQS#, LDQS/LDQS#, UDM, and LDM signal via the ODT control pin. The ODT feature is designed to improve signal integrity of the memory channel by allowing the DRAM controller to independently turn on/off termination resistance for any or all DRAM devices. The ODT function is supported for ACTIVE and STANDBY modes. It is turned off and not supported in SELF REFRESH mode. Figure 5. Functional representation of ODT VDDQ VDDQ VDDQ SW1 SW2 SW3 Rval1 Rval2 Rval3 DRAM Input Buffer Input pin Rval1 SW1 VSSQ Rval2 SW2 VSSQ Rval3 SW3 VSSQ Switch (sw1, sw2, sw3) is enabled by ODT pin. Selection among sw1, sw2, and sw3 is determined by “Rtt (nominal)” in EMR. Termination included on all DQs, DM, DQS, and DQS# pins Table 11. ODT DC Electrical Characteristics Parameter/Condition Symbol Min Nom Max Unit Note Rtt effective impedance value for EMRS(A6,A2)=0,1;75Ω Rtt1(eff) Ω 60 75 90 1 Rtt effective impedance value for EMRS(A6,A2)=1,0;150Ω Rtt2(eff) Ω 120 150 180 1 Rtt effective impedance value for EMRS(A6,A2)=1,1;50Ω Rtt3(eff) Ω 40 50 60 1 % Rtt mismatch tolerance between any pull-up/pull-down pair Rtt(mis) -6 6 2 NOTE 1: Measurement Definition for Rtt(eff): Apply VIH (ac) and VIL (ac) to test pin separately, then measure current I(VIH(ac)) and I(VIL(ac)) respectively. Rtt(eff)= VIH (ac ) − VIL (ac ) I(VIH (ac))-I(VIL (ac)) NOTE 2: Measurement Definition for Rtt (mis): Measure voltage (VM) at test pin (midpoint) with no load. ⎛ 2xVM ⎞ Rtt(mis)= ⎜ − 1⎟ × 100% ⎝ VDDQ ⎠ Rev. 1.0 15 May /2015 EtronTech EM68A16CBQC z Bank activate command The Bank Activate command is issued by holding CAS# and WE# HIGH with CS# and RAS# LOW at the rising edge of the clock. The bank addresses BA0 and BA1 are used to select the desired bank. The row addresses A0 through A12 are used to determine which row to activate in the selected bank. The Bank Activate command must be applied before any Read or Write operation can be executed. Immediately after the bank active command, the DDR2 SDRAM can accept a read or write command (with or without Auto-Precharge) on the following clock cycle. If a R/W command is issued to a bank that has not satisfied the tRCDmin specification, then additive latency must be programmed into the device to delay the R/W command which is internally issued to the device. The additive latency value must be chosen to assure tRCDmin is satisfied. Additive latencies of 0, 1, 2, 3, 4, and 5 are supported. Once a bank has been activated it must be precharged before another Bank Activate command can be applied to the same bank. The bank active and precharge times are defined as tRAS and tRP, respectively. The minimum time interval between successive Bank Activate commands to the same bank is determined (tRC). The minimum time interval between Bank Active commands is tRRD z Read and Write access modes After a bank has been activated, a Read or Write cycle can be executed. This is accomplished by setting RAS# HIGH, CS# and CAS# LOW at the clock’s rising edge. WE# must also be defined at this time to determine whether the access cycle is a Read operation (WE# HIGH) or a Write operation (WE# LOW). The DDR2 SDRAM provides a fast column access operation. A single Read or Write Command will initiate a serial Read or Write operation on successive clock cycles. The boundary of the burst cycle is strictly restricted to specific segments of the page length. Any system or application incorporating random access memory products should be properly designed, tested, and qualified to ensure proper use or access of such memory products. Disproportionate, excessive, and/or repeated access to a particular address or addresses may result in reduction of product life. z Posted CAS# Posted CAS# operation is supported to make command and data bus efficient for sustainable bandwidths in DDR2 SDRAM. In this operation, the DDR2 SDRAM allows a CAS# Read or Write command to be issued immediately after the RAS bank activate command (or any time during the RAS# -CAS#-delay time, tRCD, period). The command is held for the time of the Additive Latency (AL) before it is issued inside the device. The Read Latency (RL) is controlled by the sum of AL and the CAS latency (CL). Therefore if a user chooses to issue a R/W command before the tRCDmin, then AL (greater than 0) must be written into the EMR (1). The Write Latency (WL) is always defined as RL - 1 (Read Latency -1) where Read Latency is defined as the sum of additive latency plus CAS latency (RL=AL+CL). Read or Write operations using AL allow seamless bursts (refer to seamless operation timing diagram examples in Read burst and Write burst section) z Burst Mode Operation Burst mode operation is used to provide a constant flow of data to memory locations (Write cycle), or from memory locations (Read cycle). The parameters that define how the burst mode will operate are burst sequence and burst length. The DDR2 SDRAM supports 4 bit and 8 bit burst modes only. For 8 bit burst mode, full interleave address ordering is supported, however, sequential address ordering is nibble based for ease of implementation. The burst length is programmable and defined by the addresses A0 ~ A2 of the MRS. The burst type, either sequential or interleaved, is programmable and defined by the address bit 3 (A3) of the MRS. Seamless burst Read or Write operations are supported. Interruption of a burst Read or Write operation is prohibited, when burst length = 4 is programmed. For burst interruption of a Read or Write burst when burst length = 8 is used, see the “Burst Interruption“section of this datasheet. A Burst Stop command is not supported on DDR2 SDRAM devices. Rev. 1.0 16 May /2015 EtronTech EM68A16CBQC Table 12. Burst Definition, Addressing Sequence of Sequential and Interleave Mode Burst Length 4 8 Start Address A2 A1 A0 X 0 0 X 0 1 X 1 0 X 1 1 0 0 0 0 0 1 0 1 0 0 1 1 1 0 0 1 0 1 1 1 0 1 1 1 Sequential Interleave 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, 0, 5, 6, 7, 4 2, 3, 0, 1, 6, 7, 4, 5 3, 0, 1, 2, 7, 4, 5, 6 4, 5, 6, 7, 0, 1, 2, 3 5, 6, 7, 4, 1, 2, 3, 0 6, 7, 4, 5, 2, 3, 0, 1 7, 4, 5, 6, 3, 0, 1, 2 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 z Burst read command The Burst Read command is initiated by having CS# and CAS# LOW while holding RAS# and WE# HIGH at the rising edge of the clock. The address inputs determine the starting column address for the burst. The delay from the start of the command to when the data from the first cell appears on the outputs is equal to the value of the Read Latency (RL). The data strobe output (DQS) is driven LOW 1 clock cycle before valid data (DQ) is driven onto the data bus. The first bit of the burst is synchronized with the rising edge of the data strobe (DQS). Each subsequent data-out appears on the DQ pin in phase with the DQS signal in a source synchronous manner. The RL is equal to an additive latency (AL) plus CAS# Latency (CL). The CL is defined by the Mode Register Set (MRS), similar to the existing SDR and DDR SDRAMs. The AL is defined by the Extended Mode Register Set (1) (EMRS (1)). DDR2 SDRAM pin timings are specified for either single ended mode or differential mode depending on the setting of the EMRS “Enable DQS” mode bit; timing advantages of differential mode are realized in system design. The method by which the DDR2 SDRAM pin timings are measured is mode dependent. In single ended mode, timing relationships are measured relative to the rising or falling edges of DQS crossing at VREF. In differential mode, these timing relationships are measured relative to the crosspoint of DQS and its complement, DQS#. This distinction in timing methods is guaranteed by design and characterization. Note that when differential data strobe mode is disabled via the EMRS, the complementary pin, DQS#, must be tied externally to VSS through a 20 Ω to 10 KΩresistor to insure proper operation. z Burst write operation The Burst Write command is initiated by having CS#, CAS# and WE# LOW while holding RAS# HIGH at the rising edge of the clock. The address inputs determine the starting column address. Write latency (WL) is defined by a Read latency (RL) minus one and is equal to (AL + CL -1);and is the number of clocks of delay that are required from the time the Write command is registered to the clock edge associated to the first DQS strobe. A data strobe signal (DQS) should be driven LOW (preamble) one clock prior to the WL. The first data bit of the burst cycle must be applied to the DQ pins at the first rising edge of the DQS following the preamble. The tDQSS specification must be satisfied for each positive DQS transition to its associated clock edge during write cycles. The subsequent burst bit data are issued on successive edges of the DQS until the burst length is completed, which is 4 or 8 bit burst. When the burst has finished, any additional data supplied to the DQ pins will be ignored. The DQ Signal is ignored after the burst write operation is complete. The time from the completion of the burst Write to bank precharge is the write recovery time (WR). DDR2 SDRAM pin timings are specified for either single ended mode or differential mode depending on the setting of the EMRS “Enable DQS” mode bit; timing advantages of differential mode are realized in system design. The method by which the DDR2 SDRAM pin timings are measured is mode dependent. In single ended mode, timing relationships are measured relative to the rising or falling edges of DQS crossing at the specified AC/DC levels. In differential mode, these timing relationships are measured relative to the crosspoint of DQS and its complement, DQS#. This distinction in timing methods is guaranteed by design and characterization. Note that when differential data strobe mode is disabled via the EMRS, the complementary pin, DQS#, must be tied externally to VSS through a 20Ω to 10KΩ resistor to insure proper operation. Rev. 1.0 17 May /2015 EtronTech EM68A16CBQC z Write data mask One Write data mask (DM) pin for each 8 data bits (DQ) will be supported on DDR2 SDRAMs, Consistent with the implementation on DDR SDRAMs. It has identical timings on Write operations as the data bits, and though used in a uni-directional manner, is internally loaded identically to data bits to insure matched system timing. DM is not used during read cycles. z Precharge operation The Precharge command is used to precharge or close a bank that has been activated. The Precharge Command is triggered when CS#, RAS# and WE# are LOW and CAS# is HIGH at the rising edge of the clock. The Precharge Command can be used to precharge each bank independently or all banks simultaneously. Three address bits A10, BA1, and BA0 are used to define which bank to precharge when the command is issued. Table 13. Bank Selection for Precharge by address bits A10 BA1 BA0 Precharged Bank(s) LOW LOW LOW LOW HIGH LOW LOW HIGH HIGH DON’T CARE LOW HIGH LOW HIGH DON’T CARE Bank 0 only Bank 1 only Bank 2 only Bank 3 only ALL Banks z Burst read operation followed by precharge Minimum Read to precharge command spacing to the same bank = AL + BL/2 + max (RTP, 2) - 2 clocks. For the earliest possible precharge, the precharge command may be issued on the rising edge which “Additive latency (AL) + BL/2 clocks” after a Read command. A new bank active (command) may be issued to the same bank after the RAS# precharge time (tRP). A precharge command cannot be issued until tRAS is satisfied. The minimum Read to Precharge spacing has also to satisfy a minimum analog time from the rising clock edge that initiates the last 4-bit prefetch of a Read to Precharge command. This time is called tRTP (Read to Precharge). For BL = 4 this is the time from the actual read (AL after the Read command) to Precharge command. For BL = 8 this is the time from AL + 2 clocks after the Read to the Precharge command. z Burst Write operation followed by precharge Minimum Write to Precharge command spacing to the same bank = WL + BL/2 + tWR. For write cycles, a delay must be satisfied from the completion of the last burst write cycle until the Precharge command can be issued. This delay is known as a write recovery time (tWR) referenced from the completion of the burst write to the Precharge command. No Precharge command should be issued prior to the tWR delay, as DDR2 SDRAM does not support any burst interrupt by a Precharge command. tWR is an analog timing parameter and is not the programmed value for tWR in the MRS. z Auto precharge operation Before a new row in an active bank can be opened, the active bank must be precharged using either the Precharge Command or the auto-precharge function. When a Read or a Write Command is given to the DDR2 SDRAM, the CAS# timing accepts one extra address, column address A10, to allow the active bank to automatically begin precharge at the earliest possible moment during the burst read or write cycle. If A10 is LOW when the READ or WRITE Command is issued, then normal Read or Write burst operation is executed and the bank remains active at the completion of the burst sequence. If A10 is HIGH when the Read or Write Command is issued, then the auto-precharge function is engaged. During auto-precharge, a Read Command will execute as normal with the exception that the active bank will begin to precharge on the rising edge which is CAS latency (CL) clock cycles before the end of the read burst. Auto-precharge also be implemented during Write commands. The precharge operation engaged by the Auto precharge command will not begin until the last data of the burst write sequence is properly stored in the memory array. This feature allows the precharge operation to be partially or completely hidden during burst Read cycles (dependent upon CAS latency) thus improving system performance for random data access. The RAS# lockout circuit internally delays the Precharge operation until the array restore operation has been completed (tRAS satisfied) so that the auto precharge command may be issued with any Read or Write command. Rev. 1.0 18 May /2015 EtronTech EM68A16CBQC z Burst read with auto precharge If A10 is HIGH when a Read Command is issued, the Read with Auto-Precharge function is engaged. The DDR2 SDRAM starts an Auto-Precharge operation on the rising edge which is (AL + BL/2) cycles later from the Read with AP command if tRAS(min) and tRTP are satisfied. If tRAS(min) is not satisfied at the edge, the start point of Auto-Precharge operation will be delayed until tRAS(min) is satisfied. If tRTP(min) is not satisfied at the edge, the start point of Auto-precharge operation will be delayed until tRTP(min) is satisfied. In case the internal precharge is pushed out by tRTP, tRP starts at the point where the internal precharge happens (not at the next rising clock edge after this event). So for BL = 4 the minimum time from Read with Auto-Precharge to the next Activate command becomes AL + tRTP + tRP. For BL = 8 the time from Read with Auto-Precharge to the next Activate command is AL + 2 + tRTP + tRP. Note that both parameters tRTP and tRP have to be rounded up to the next integer value. In any event internal precharge does not start earlier than two clocks after the last 4-bit prefetch. A new bank active (command) may be issued to the same bank if the following two conditions are satisfied simultaneously: (1) The RAS# precharge time (tRP) has been satisfied from the clock at which the Auto-Precharge begins. (2) The RAS# cycle time (tRC) from the previous bank activation has been satisfied. z Burst write with auto precharge If A10 is HIGH when a Write Command is issued, the Write with Auto-Precharge function is engaged. The DDR2 SDRAM automatically begins precharge operation after the completion of the burst write plus Write recovery time (tWR). The bank undergoing auto-precharge from the completion of the write burst may be reactivated if the following two conditions are satisfied. (1) The data-in to bank activate delay time (WR + tRP) has been satisfied. (2) The RAS# cycle time (tRC) from the previous bank activation has been satisfied. Table 14. Precharge &Auto Precharge Clariification Minimum Delay between “From Unit Notes Command” to “To Command” Precharge (to same Bank as Read) AL+BL/2+max(RTP,2)-2 Read tCK 1,2 Precharge All AL+BL/2+max(RTP,2)-2 Precharge (to same Bank as Read w/AP) AL+BL/2+max(RTP,2)-2 tCK Read w/AP 1,2 Precharge All AL+BL/2+max(RTP,2)-2 Precharge (to same Bank as Write) WL+BL/2+tWR tCK Write 2 Precharge All WL+BL/2+tWR Precharge (to same Bank as Write w/AP) WL+BL/2+tWR tCK Write w/AP 2 Precharge All WL+BL/2+tWR Precharge (to same Bank as Precharge) 1 tCK Precharge 2 Precharge All 1 Precharge 1 tCK Precharge All 2 Precharge All 1 NOTE 1: RTP [cycles] =RU {tRTP [ns]/tCK (avg) [ns]}, where RU stands for round up. NOTE 2: For a given bank, the precharge period should be counted from the latest precharge command, either one bank precharge or precharge all, issued to that bank.The prechrage period is satisfied after tRP or tRPall(=tRP for 4 bank device) depending on the latest precharge command issued to that bank. From Command Rev. 1.0 To Command 19 May /2015 EtronTech EM68A16CBQC z Refresh command When CS#, RAS# and CAS# are held LOW and WE# HIGH at the rising edge of the clock, the chip enters the Refresh mode (REF). All banks of the DDR2 SDRAM must be precharged and idle for a minimum of the Precharge time (tRP) before the Refresh command (REF) can be applied. An address counter, internal to the device, supplies the bank address during the refresh cycle. No control of the external address bus is required once this cycle has started. When the refresh cycle has completed, all banks of the DDR2 SDRAM will be in the precharged (idle) state. A delay between the Refresh command (REF) and the next Activate command or subsequent Refresh command must be greater than or equal to the Refresh cycle time (tRFC).To allow for improved efficiency in scheduling and switching between tasks, some flexibility in the absolute refresh interval is provided. A maximum of eight Refresh commands can be posted to any given DDR2 SDRAM, meaning that the maximum absolute interval between any Refresh command and the next Refresh command is 9 * tREFI. z Self refresh operation The Self Refresh command can be used to retain data in the DDR2 SDRAM, even if the rest of the system is powered down. When in the Self Refresh mode, the DDR2 SDRAM retains data without external clocking. The DDR2 SDRAM device has a built-in timer to accommodate Self Refresh operation. The Self Refresh Command is defined by having CS#, RAS#, CAS# and CKE# held LOW with WE# HIGH at the rising edge of the clock. ODT must be turned off before issuing Self Refresh command, by either driving ODT pin LOW or using EMRS command. Once the Command is registered, CKE must be held LOW to keep the device in Self Refresh mode. The DLL is automatically disabled upon entering Self Refresh and is automatically enabled upon exiting Self Refresh. When the DDR2 SDRAM has entered Self Refresh mode all of the external signals except CKE, are “don’t care”. For proper Self Refresh operation all power supply pins (VDD, VDDQ, VDDL and VREF) must be at valid levels. The DRAM initiates a minimum of one refresh command internally within tCKE period once it enters Self Refresh mode. The clock is internally disabled during Self Refresh Operation to save power. The minimum time that the DDR2 SDRAM must remain in Self Refresh mode is tCKE. The user may change the external clock frequency or halt the external clock one clock after Self Refresh entry is registered, however, the clock must be restarted and stable before the device can exit Self Refresh operation. The procedure for exiting Self Refresh requires a sequence of commands. First, the clock must be stable prior to CKE going back HIGH. Once Self Refresh Exit is registered, a delay of at least tXSNR must be satisfied before a valid command can be issued to the device to allow for any internal refresh in progress. CKE must remain HIGH for the entire Self Refresh exit period tXSRD for proper operation except for Self Refresh re-entry. Upon exit from Self Refresh, the DDR2 SDRAM can be put back into Self Refresh mode after waiting at least tXSNR period and issuing one refresh command(refresh period of tRFC). NOP or deselect commands must be registered on each positive clock edge during the Self Refresh exit interval tXSNR. ODT should be turned off during tXSRD. The use of Self Refresh mode introduces the possibility that an internally timed refresh event can be missed when CKE is raised for exit from Self Refresh mode. Upon exit from Self Refresh, the DDR2 SDRAM requires a minimum of one extra auto refresh command before it is put back into Self Refresh mode. Rev. 1.0 20 May /2015 EtronTech EM68A16CBQC z Power-Down Power-down is synchronously entered when CKE is registered LOW along with NOP or Deselect command. No read or write operation may be in progress when CKE goes LOW. These operations are any of the following: read burst or write burst and recovery. CKE is allowed to go LOW while any of other operations such as row activation, precharge or autoprecharge, mode register or extended mode register command time, or autorefresh is in progress. The DLL should be in a locked state when power-down is entered. Otherwise DLL should be reset after exiting power-down mode for proper read operation. If power-down occurs when all banks are precharged, this mode is referred to as Precharge Power-down; if power-down occurs when there is a row active in any bank, this mode is referred to as Active Power-down. For Active Power-down two different power saving modes can be selected within the MRS register, address bit A12. When A12 is set to “LOW” this mode is referred as “standard active power-down mode” and a fast power-down exit timing defined by the tXARD timing parameter can be used. When A12 is set to “HIGH” this mode is referred as a power saving “LOW power active power-down mode”. This mode takes longer to exit from the power-down mode and the tXARDS timing parameter has to be satisfied. Entering power-down deactivates the input and output buffers, excluding CK, CK#, ODT and CKE. Also the DLL is disabled upon entering precharge powerdown or slow exit active power-down, but the DLL is kept enabled during fast exit active power-down. In powerdown mode, CKE LOW and a stable clock signal must be maintained at the inputs of the DDR2 SDRAM, and all other input signals are “Don’t Care”. Power-down duration is limited by 9 times tREFI of the device. The power-down state is synchronously exited when CKE is registered HIGH (along with a NOP or Deselect command). A valid, executable command can be applied with power-down exit latency, tXP, tXARD or tXARDS, after CKE goes HIGH. Power-down exit latencies are defined in the AC spec table of this data sheet. z Asynchronous CKE LOW Event DRAM requires CKE to be maintained “HIGH” for all valid operations as defined in this datasheet. If CKE asynchronously drops “LOW” during any valid operation DRAM is not guaranteed to preserve the contents of array. If this event occurs, memory controller must satisfy DRAM timing specification tDelay before turning off the clocks. Stable clocks must exist at the input of DRAM before CKE is raised “HIGH” again. DRAM must be fully re-initialized. DRAM is ready for normal operation after the initialization sequence. z Input clock frequency change during precharge power down DDR2 SDRAM input clock frequency can be changed under following condition: DDR2 SDRAM is in precharged power down mode. ODT must be turned off and CKE must be at logic LOW level. A minimum of 2 clocks must be waited after CKE goes LOW before clock frequency may change. SDRAM input clock frequency is allowed to change only within minimum and maximum operating frequency specified for the particular speed grade. During input clock frequency change, ODT and CKE must be held at stable LOW levels. Once input clock frequency is changed, stable new clocks must be provided to DRAM before precharge power down may be exited and DLL must be RESET via EMRS after precharge power down exit. Depending on new clock frequency an additional MRS command may need to be issued to appropriately set the WR, CL etc. During DLL re-lock period, ODT must remain off. After the DLL lock time, the DRAM is ready to operate with new clock frequency. z No operation command The No Operation Command should be used in cases when the DDR2 SDRAM is in an idle or a wait state. The purpose of the No Operation Command (NOP) is to prevent the DDR2 SDRAM from registering any unwanted commands between operations. A No Operation Command is registered when CS# is LOW with RAS#, CAS#, and WE# held HIGH at the rising edge of the clock. A No Operation Command will not terminate a previous operation that is still executing, such as a burst read or write cycle. z Deselect command The Deselect Command performs the same function as a No Operation Command. Deselect Command occurs when CS# is brought HIGH at the rising edge of the clock, the RAS#, CAS#, and WE# signals become don’t cares. Rev. 1.0 21 May /2015 EtronTech EM68A16CBQC Table 15. Absolute Maximum DC Ratings Symbol Parameter Values Unit Note VDD Voltage on VDD pin relative to Vss -1.0 ~ 2.3 V 1,3 VDDQ Voltage on VDDQ pin relative to Vss -0.5 ~ 2.3 V 1,3 VDDL Voltage on VDDL pin relative to Vss -0.5 ~ 2.3 V 1,3 VIN, VOUT Voltage on any pin relative to Vss -0.5 ~ 2.3 V 1,4 TSTG Storage temperature -55~100 1,2 °C NOTE1: Stress greater than those listed under “Absolute Maximum Ratings” may cause permanent damage to the devices. 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. NOTE2: Storage temperature is the case temperature on the center/top side of the DRAM. NOTE3: When VDD and VDDQ and VDDL are less than 500mV, Vref may be equal to or less than 300mV. NOTE4: Voltage on any input or I/O may not exceed voltage on VDDQ. Table 16. Operating Temperature Condition Symbol Parameter Values Unit Note Industrial temperature -40~95 TOPER °C 1, 2 NOTE1: Operating temperature is the case surface temperature on center/top of the DRAM. NOTE2: The operating temperature range is the temperature where all DRAM specification will be supported. Outside of this temperature range, even if it is still within the limit of stress condition, some deviation on portion of operating specification may be required.During operation, the DRAM case temperature must be maintained between 0-85°C under all other specification parameter. Supporting 0 - 85 °C with full JEDEC AC & DC specifications and being able to extend to 95 °C withdoubling auto-refresh commands in frequency to a 32 ms period ( tREFI = 3.9 us). Supporting higher temperature Self-Refresh entry via the control of EMSR(2) bit A7. Table 17. Recommended DC Operating Conditions (SSTL_1.8) Symbol Parameter Min. Typ. Max. Unit Note VDD Power supply voltage 1.7 1.8 1.9 V 1 VDDL Power supply voltage for DLL 1.7 1.8 1.9 V 5 VDDQ Power supply voltage for I/O Buffer 1.7 1.8 1.9 V 1,5 VREF Input reference voltage 0.49 x VDDQ 0.5 x VDDQ 0.51 x VDDQ mV 2,3 VTT Termination voltage VREF - 0.04 VREF VREF + 0.04 V 4 NOTE1: There is no specific device VDD supply voltage requirement for SSTL_18 compliance. However under all conditions VDDQ must be less than or equal to VDD. NOTE2: The value of VREF may be selected by the user to provide optimum noise margin in the system. Typically the value of VREF is expected to be about 0.5 x VDDQ of the transmitting device and VREF is expected to track variations in VDDQ. NOTE3: Peak to peak ac noise on VREF may not exceed +/-2 % VREF (dc). NOTE4: VTT of transmitting device must track VREF of receiving device. NOTE5: VDDQ tracks with VDD, VDDL tracks with VDD. AC parameters are measured with VDD, VDDQ and VDDL tied together Rev. 1.0 22 May /2015 EtronTech EM68A16CBQC Table 18. Input logic level Symbol Parameter -18I -25I/3I Unit Note Min. Max. Min. Max. VREF + 0.125 VDDQ + 0.3 VREF + 0.125 VDDQ + 0.3 V -0.3 VREF - 0.125 V VREF + 0.2 VDDQ + Vpeak V 1 VIH (dc) DC Input logic High Voltage VIL (dc) DC Input Low Voltage -0.3 VREF - 0.125 VIH (ac) AC Input High Voltage VREF + 0.2 - VIL (ac) AC Input Low Voltage - VREF – 0.2 VSSQ - Vpeak VREF – 0.2 V 1 VID (ac) AC Differential Voltage 0.5 VDDQ + 0.6 0.5 VDDQ V 1 0.5 x 0.5 x 0.5 x 0.5 x VIX (ac) AC Differential crosspoint Voltage V VDDQ -0.175 VDDQ+0.175 VDDQ -0.175 VDDQ+0.175 NOTE1: Refer to Overshoot/undershoot specifications for Vpeak value: maximum peak amplitude allowed for overshoot and undershoot. Table 19. AC Input test conditions Symbol Parameter Values Unit Note VREF Input reference voltage 0.5 x VDDQ V 1 VSWING(max) Input signal maximum peak to peak swing 1.0 V 1 Slew Rate Input signal minimum slew rate 1.0 V/ns 2, 3 NOTE1: Input waveform timing is referenced to the input signal crossing through the VIH /IL (ac) level applied to the device under test. NOTE2: The input signal minimum slew rate is to be maintained over the range from VREF to VIH(ac) min for rising edges and the range from VREF to VIL (ac) max for falling edges . NOTE3: AC timings are referenced with input waveforms switching from VIL (ac) to VIH (ac) on the positive transitions and VIH (ac) to VIL (ac) on the negative transitions. Table 20. Differential AC output parameters Symbol Values Parameter Min. Unit Note Max. Vox(ac) AC Differential Cross Point Voltage 0.5xVDDQ-0.125 0.5xVDDQ+0.125 V 1 NOTE1: The typical value of VOX (ac) is expected to be about 0.5 x VDDQ of the transmitting device and VOX (ac) is expected to track variations in VDDQ. VOX (ac) indicates the voltage at which differential output signals must cross. Table 21. AC overshoot/undershoot specification for address and control pins (A0-A12, BA0-BA1, CS#, RAS#, CAS#, WE#, CKE, ODT) Parameter -18I -25I -3I Unit Maximum peak amplitude allowed for overshoot area 0.5 0.5 0.5 V Maximum peak amplitude allowed for undershoot area 0.5 0.5 0.5 V Maximum overshoot area above VDD 0.5 0.66 0.8 V-ns Maximum undershoot area below VSS 0.5 0.66 0.8 V-ns Rev. 1.0 23 May /2015 EtronTech EM68A16CBQC Table 22. AC overshoot/undershoot specification for clock, data, strobe, and mask pins (DQ, UDQS, LDQS, UDQS#, LDQS#, DM, CK, CK#) Parameter -18I -25I -3I Unit Maximum peak amplitude allowed for overshoot area 0.5 0.5 0.5 V Maximum peak amplitude allowed for undershoot area 0.5 0.5 0.5 V Maximum overshoot area above VDD 0.19 0.23 0.23 V-ns Maximum undershoot area below VSS 0.19 0.23 0.23 V-ns Table 23. Output AC test conditions Symbol VOTR Parameter Values Output timing measurement reference level Unit Note 0.5xVDDQ V 1 NOTE1: The VDDQ of the device under test is referenced. Table 24. Output DC current drive Symbol IOH(dc) Parameter Output minimum source DC current Values Unit Note -13.4 mA 1, 3, 4 IOL(dc) Output minimum sink DC current 13.4 mA 2, 3, 4 NOTE1: VDDQ = 1.7V; VOUT = 1420 mV. (VOUT - VDDQ)/IOH must be less than 21 Ω for values of VOUT between VDDQ and VDDQ - 280 mV. NOTE2: VDDQ = 1.7V; VOUT = 280 mV. VOUT/IOL must be less than 21 Ω for values of VOUT between 0 V and 280 mV. NOTE3: The dc value of VREF applied to the receiving device is set to VTT NOTE4: The values of IOH(dc) and IOL(dc) are based on the conditions given in Notes 1 and 2. They are used to test device drive current capability to ensure VIH min plus a noise margin and VIL max minus a noise margin are delivered to an SSTL_18 receiver. The actual current values are derived by shifting the desired driver operating point (see JEDEC standard: Section 3.3 of JESD8-15A) along a 21 Ω load line to define a convenient driver current for measurement. Table 25. Capacitance (VDD = 1.8V, f = 1MHz, TOPER = 25 °C) Symbol CIN CCK CI/O DCIN DCCK DCIO Values Parameter Input Capacitance, all other input-only pins Input Capacitance (CK, CK#) Input/Output Capacitance DM, DQ, DQS, DQS# Delta Input Capacitance: Command and Address Delta Input Capacitance: CK, CK# Delta Input/Output Capacitance: DM, DQ, DQS, DQS# Min. 1.0 1.0 2.5 - Max. 1.75 2.0 3.5 0.25 0.25 0.5 Unit pF pF pF pF pF pF NOTE: These parameters are periodically sampled and are not 100% tested. Rev. 1.0 24 May /2015 EtronTech EM68A16CBQC Table 26. IDD specification parameters and test conditions (VDD = 1.8V ± 0.1V, TOPER = -40~95 °C) Parameter & Test Condition Operating one bank active-precharge current: tCK =tCK (min), tRC = tRC (min), tRAS = tRAS(min); CKE is HIGH, CS# is HIGH between valid commands; Address bus inputs are SWITCHING; Data bus inputs are SWITCHING Operating one bank active-read-precharge current: IOUT = 0mA; BL = 4, CL = CL (min), AL = 0; tCK = tCK (min),tRC = tRC (min), tRAS = tRAS(min), tRCD = tRCD (min);CKE is HIGH, CS# is HIGH between valid commands;Address bus inputs are switching; Data pattern is same as IDD4W Precharge power-down current: All banks idle;tCK =tCK (min); CKE is LOW; Other control and address bus inputs are STABLE; Data bus inputs are FLOATING Precharge quiet standby current: All banks idle; tCK =tCK (min); CKE is HIGH, CS# is HIGH; Other control and address bus inputs are STABLE; Data bus inputs are FLOATING Precharge standby current: All banks idle; tCK = tCK (min); CKE is HIGH, CS# is HIGH; Other control and address bus inputs are SWITCHING; Data bus inputs are SWITCHING Active power-down current: MRS(A12)=0 All banks open; tCK =tCK (min); CKE is LOW; Other control and address bus inputs are STABLE; Data bus inputs are MRS(A12)=1 FLOATING Active standby current: All banks open; tCK = tCK(min), tRAS = tRAS (max), tRP = tRP (min); CKE is HIGH,CS# is HIGH between valid commands; Other control and address bus inputs are SWITCHING; Data bus inputs are SWITCHING Operating burst write current: All banks open,continuous burst writes; BL = 4, CL = CL (min), AL = 0; tCK= tCK (min), tRAS = tRAS (max), tRP = tRP (min); CKE is HIGH, CS# is HIGH between valid commands; Address bus inputs are switching; Data bus inputs are switching Operating burst read current: All banks open, continuous burst reads, IOUT = 0mA; BL = 4, CL = CL (min), AL = 0; tCK = tCK (min), tRAS = tRAS (max), tRP = tRP (min); CKE is HIGH, CS# is HIGH between valid commands; Address bus inputs are SWITCHING; Data bus inputs are SWITCHING Burst refresh current: tCK = tCK (min); refresh command at every tRFC (min) interval; CKE is HIGH, CS# is HIGH between valid commands; Other control and address bus inputs are SWITCHING; Data bus inputs are SWITCHING Self refresh current: CK and CK# at 0V; CKE ≤ 0.2V;Other control and address bus inputs are FLOATING; Data bus inputs are FLOATING Operating bank interleave read current: All bank interleaving reads, IOUT= 0mA; BL = 4, CL = CL (min), AL =tRCD (min) - 1 x tCK (min); tCK = tCK (min), tRC = tRC (min), tRRD = tRRD (min), tRCD = tRCD (min); CKE is HIGH, CS# is HIGH between valid commands; Address bus inputs are STABLE during DESELECTs.Data pattern is same as IDD4R Rev. 1.0 -18I -25I Max. -3I IDD0 70 60 55 mA IDD1 80 70 65 mA IDD2P 6 6 6 mA IDD2Q 40 35 35 mA IDD2N 40 35 35 mA 20 20 20 mA 14 14 14 mA IDD3N 60 55 55 mA IDD4W 125 105 95 mA IDD4R 120 100 90 mA IDD5B 80 75 70 mA IDD6 6 6 6 mA IDD7 165 140 120 mA Symbol 25 Unit IDD3P May /2015 EtronTech EM68A16CBQC Table 27. Electrical Characteristics and Recommended A.C. Operating Conditions (VDD = 1.8V ± 0.1V, TOPER = -40~95 °C) Symbol tCK -18I Min. Max. -25I Min. Max. Min. Max. CL=4 3.75 8 3.75 8 3.75 8 CL=5 2.5 8 2.5 8 3 8 CL=6 2.5 8 2.5 8 - - CL=7 1.875 8 - - - - 0.52 0.48 0.52 0.48 0.52 0.52 0.48 0.52 0.48 Parameter Clock cycle time tCH(avg) tCL(avg) WL Average clock HIGH pulse width 0.48 Average Clock LOW pulse width 0.48 tDQSS DQS latching rising transitions to associated clock edges tDSS tDSH Write command to DQS associated clock edge RL-1 -3I RL-1 0.52 RL-1 Unit Specific Notes ns ns ns ns tCK tCK tCK 15, 33, 34 15, 33, 34 15, 33, 34 15, 33, 34 34, 35 34, 35 -0.25 0.25 -0.25 0.25 -0.25 0.25 tCK 28 DQS falling edge to CK setup time 0.2 - 0.2 - 0.2 - 28 DQS falling edge hold time from CK 0.2 - 0.2 - 0.2 - tCK tCK tDQSH DQS input HIGH pulse width 0.35 - 0.35 - 0.35 - tCK tDQSL tWPRE tWPST DQS input LOW pulse width 0.35 - 0.35 - 0.35 - Write preamble 0.35 - 0.35 - 0.35 - Write postamble 0.4 0.6 0.4 0.6 0.4 0.6 tCK tCK tCK 10 tIS(base) Address and Control input setup time 0.125 - 0.175 - 0.2 - ns 5, 7, 9, 22, 27 tIH(base) Address and Control input hold time 0.2 - 0.25 - 0.275 - ns 5, 7, 9, 23, 27 tIPW Control & Address input pulse width for each input 0.6 - 0.6 - 0.6 - tCK tDS(base) DQ & DM input setup time (differential strobe) 0 - 0.05 - 0.1 - ns 6, 7, 8, 20, 26, 29 tDH(base) DQ & DM input hold time (differential strobe) 0.075 - 0.125 - 0.175 - ns 6, 7, 8, 21, 26, 29 tCK ns ns ns ns ns ns ns ns ns tCK tCK ns tCK ns ns ns ns tCK ns tCK tCK tCK tDIPW tAC tDQSCK tHZ tLZ(DQS) tLZ(DQ) tDQSQ tHP tQHS tQH tRPRE tRPST tRRD tCCD tWR tDAL tWTR tRTP tCKE tXSNR tXSRD tXP tXARD Rev. 1.0 DQ and DM input pulse width for each input 0.35 - 0.35 - 0.35 - DQ output access time from CK, CK# -0.35 0.35 -0.4 0.4 -0.45 0.45 DQS output access time from CK, CK# -0.325 0.325 -0.35 0.35 -0.4 0.4 Data-out high-impedance time from CK, CK# DQS(DQS#) low-impedance time from CK, CK# DQ low-impedance time from CK, CK# - tAC(min) 2tAC(min) DQS-DQ skew for DQS and associated DQ signals CK half pulse width tAC(max) tAC(max) tAC(max) tAC(max) tAC(min) tAC(max) tAC(min) tAC(max) tAC(max) 2tAC(min) tAC(max) 2tAC(min) tAC(max) - - - 0.175 - 0.2 - 0.24 min(tCL, tCH) - min(tCL, tCH) - min(tCL, tCH) - DQ hold skew factor - 0.25 - 0.3 - 0.34 tHP -tQHS - tHP -tQHS - tHP -tQHS - Read preamble 0.9 1.1 0.9 1.1 0.9 1.1 Read postamble 0.4 0.6 0.4 0.6 0.4 0.6 Active to active command period 7.5 - 7.5 - 7.5 - CAS# to CAS# command delay 2 - 2 - 2 - Write recovery time 15 - 15 - 15 - WR + tRP - WR + tRP - WR + tRP - Internal Write to Read Command Delay 7.5 - 7.5 - 7.5 - Internal read to precharge command delay 7.5 - 7.5 - 7.5 - 3 - 3 - 3 - tRFC+10 - tRFC+10 - tRFC+10 - 200 - 200 - 200 - DQ/DQS output hold time from DQS Auto Power write recovery + precharge time CKE minimum pulse width Exit self refresh to non-read command delay Exit self refresh to a read command Exit precharge power down to any command 3 - 2 - 2 - Exit active power down to read command 3 - 2 - 2 - 26 38 38 18, 38 18, 38 18, 38 13 11, 12, 35 12, 36 37 19, 39 19, 40 4, 30 30 14, 31 3, 24, 30 3, 30 25 30 1 May /2015 EtronTech EM68A16CBQC tXARDS Exit active power down to read command (slow exit, lower power) tAOND ODT turn-on delay tAON 10-AL - 8-AL - 7-AL - tCK 1, 2 2 2 2 2 2 2 tCK 16 ODT turn-on tAC(min) tAC(max)+ 2.575 tAC(min) tAC(max)+ 0.7 tAC(min) tAC(max)+ 0.7 ns 6, 16, 38 tAONPD ODT turn-on (Power-Down mode) 2 tCK 2 tCK 3 tCK tAC(min) +tAC(max) tAC(min)+2 +tAC(max) tAC(min)+2 +tAC(max) +2 +1 +1 +1 ns tAOFD ODT turn-off delay tAOF ODT turn-off tAOFPD ODT turn-off (Power-Down mode) tANPD tAXPD tMRD tMOD tOIT ODT to power down entry latency 4 ODT power down exit latency 11 - 8 - 8 - Mode register set command cycle time 2 - 2 - 2 - MRS command to ODT update delay 0 12 0 12 0 12 OCD drive mode output delay 0 12 0 12 0 12 tCK tCK tCK ns ns tIS+tCK+tIH - tIS+tCK+tIH - tIS+tCK+tIH - ns 15 2.5 2.5 2.5 2.5 2.5 2.5 tCK tAC(min) tAC(max)+ tAC(min) tAC(max)+ tAC(min) tAC(max)+ ns 0.6 Minimum time clocks remains ON after CKE asynchronously drops LOW tRFC Refresh to active/Refresh command time Average periodic refresh interval tRCD tRP tRC tRAS RAS# to CAS# Delay time 0.6 2.5 tCK 2.5 tCK 2.5 tCK tAC(min)+2 +tAC(max) tAC(min)+2 +tAC(max) tAC(min)+2 +tAC(max) +1 +1 +1 tDelay tREFI 0.6 - 3 - 3 - 17, 42 17, 41, 42 ns 30 30 75 - 75 - 75 - ns 43 -40°C≦TC≦ +85°C - 7.8 - 7.8 - 7.8 µs 43 +85°C＜TC≦ +95°C - 3.9 - 3.9 - 3.9 43 13.125 - 12.5 - 15 - µs ns ns ns ns Row precharge Delay time 13.125 - 12.5 - 15 - Row cycle Delay time 58.125 - 57.5 - 60 - Row active Delay time 45 70k 45 70k 45 70k General notes, which may apply for all AC parameters: NOTE 1: DDR2 SDRAM AC timing reference load The below figure represents the timing reference load used in defining the relevant timing parameters of the part. It is not intended to be either a precise representation of the typical system environment or a depiction of the actual load presented by a production tester. Figure 6. AC timing reference load VDDQ DUT DQ Ouput DQS DQS# 25Ω VTT=VDDQ/2 Timing reference point The output timing reference voltage level for single ended signals is the crosspoint with VTT. The output timing reference voltage level for differential signals is the crosspoint of the true (e.g. DQS) and the complement (e.g. DQS#) signal. Rev. 1.0 27 May /2015 EtronTech EM68A16CBQC NOTE 2: Slew Rate Measurement Levels a) Output slew rate for falling and rising edges is measured between VTT - 250 mV and VTT + 250 mV for single ended signals. For differential signals (e.g. DQS – DQS#) output slew rate is measured between DQS – DQS# = - 500 mV and DQS – DQS# = + 500 mV. Output slew rate is guaranteed by design, but is not necessarily tested on each device. b) Input slew rate for single ended signals is measured from VREF (dc) to VIH (ac), min for rising edges and from VREF(dc) to VIL(ac),max for falling edges.For differential signals (e.g. CK – CK#) slew rate for rising edges is measured from CK – CK# = - 250 mV to CK -CK# = + 500 mV (+ 250 mV to - 500 mV for falling edges). c) VID is the magnitude of the difference between the input voltage on CK and the input voltage on CK#, or betweenDQS and DQS# for differential strobe. NOTE 3: DDR2 SDRAM output slew rate test load Output slew rate is characterized under the test conditions as bellow Figure 6.1 Slew rate test load VDDQ DQ DUT DQS Ouput 25Ω DQS# VTT=VDDQ/2 Test point NOTE 4: Differential data strobe DDR2 SDRAM pin timings are specified for either single ended mode or differential mode depending on the Setting of the EMRS “Enable DQS” mode bit; timing advantages of differential mode are realized in system design. The method by which the DDR2 SDRAM pin timings are measured is mode dependent. In single ended mode, timing relationships are measured relative to the rising or falling edges of DQS crossing at VREF. In differential mode, these timing relationships are measured relative to the crosspoint of DQS and its complement, DQS#. This distinction in timing methods is guaranteed by design and characterization. Note that when differential data strobe mode is disabled via the EMRS, the complementary pin, DQS#, must be tied externally to VSS through a 20 Ω to 10 kΩ resistor to insure proper operation. NOTE 5: AC timings are for linear signal transitions. NOTE 6: All voltages are referenced to VSS. NOTE 7: These parameters guarantee device behavior, but they are not necessarily tested on each device.They may be guaranteed by device design or tester correlation. NOTE 8: 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 device operation are guaranteed for the full voltage range specified. Rev. 1.0 28 May /2015 EtronTech EM68A16CBQC Specific notes for dedicated AC parameters NOTE 1: User can choose which active power down exit timing to use via MRS (bit 12). tXARD is expected to be used for fast active power down exit timing. tXARDS is expected to be used for slow active power down exit timing where a lower power value is defined by each vendor data sheet. NOTE 2: AL=Additive Latency. NOTE 3: This is a minimum requirement. Minimum read to precharge timing is AL+BL/2 provided that the tRTP and tRAS (min) have been satisfied. NOTE 4: A minimum of two clocks (2* tCK ) is required irrespective of operating frequency. NOTE 5: Timings are specified with command/address input slew rate of 1.0 V/ns. NOTE 6: Timings are specified with DQs, DM, and DQS’s (in single ended mode) input slew rate of 1.0V/ns. NOTE 7: Timings are specified with CK/CK# differential slew rate of 2.0 V/ns. Timings are guaranteed for DQS signals with a differential slew rate of 2.0 V/ns in differential strobe mode and a slew rate of 1 V/ns in single ended mode. NOTE 8: Data setup and hold time derating. For all input signals the total tDS (setup time) and tDH (hold time) required is calculated by adding the data sheet. tDS(base) and tDH(base) value to the ∆tDS and ∆tDH derating value respectively. Example: tDS (total setup time) =tDS (base) + ∆tDS.For slew rates in between the values listed in Tables 28, the derating values may obtained by linear interpolation.These values are typically not subject to production test. They are verified by design and characterization. Table 28. DDR2-667/800/1066 tDS/tDH derating with differential data strobe △tDS, △tDH derating values for DDR2-667, DDR2-800, DDR2-1066 (All units in ‘ps’; the note applies to the entire table) DQS,DQS# Differential Slew Rate 4.0 V/ns 3.0 V/ns 2.0 V/ns 1.8 V/ns 1.6 V/ns 1.4 V/ns 1.2 V/ns 1.0 V/ns 0.8 V/ns DQ Sle w Rate V/ns 2.0 1.5 1.0 0.9 0.8 0.7 0.6 0.5 0.4 Rev. 1.0 △tDS △tDH △tDS △tDH △tDS △tDH △tDS △tDH △tDS △tDH △tDS △tDH △tDS △tDH △tDS △tDH △tDS 100 45 100 45 100 45 - - - - - - - - - - - - 67 21 67 21 67 21 79 33 - - - - - - - - - - 0 0 0 0 0 0 12 12 24 24 - - - - - - - - - - -5 -14 -5 -14 7 -2 19 10 31 22 - - - - - - - - - - -13 -31 -1 -19 11 -7 23 5 35 17 - - - - - - - - - - -10 -42 2 -30 14 -18 26 -6 38 6 - - - - - - - - - - -10 -59 2 -47 14 -35 26 -23 38 -11 - - - - - - - - - - -24 -89 -12 -77 0 -65 12 -53 - - - - - - - - - - - - -52 -140 -40 -128 -28 -116 29 △tDH May /2015 EtronTech EM68A16CBQC NOTE 9: tIS and tIH (input setup and hold) derating For all input signals the total tIS (setup time) and tIH (hold time) required is calculated by adding the data sheet tIS(base) and tIH(base) value to the ∆tIS and ∆tIH derating value respectively. Example: tIS (total setup time) = tIS(base) + ∆tIS For slew rates in between the values listed in Tables 29, the derating values may obtained by linear interpolation.These values are typically not subject to production test. They are verified by design and characterization Table 29. Derating values for DDR2-667, DDR2-800, DDR2-1066 Command/ Address Slew rate (V/ns) △tIS and △tIH Derating Values for DDR2-667, DDR2-800, DDR2-1066 CK,CK# Differential Slew Rate 2.0 V/ns 1.5 V/ns 1.0 V/ns △tIS △tIH △tIS △tIH △tIS △tIH 4.0 +150 +94 +180 +124 +210 +154 3.5 +143 +89 +173 +119 +203 +149 3.0 +133 +83 +163 +113 +193 +143 2.5 +120 +75 +150 +105 +180 +135 2.0 +100 +45 +130 +75 +160 +105 1.5 +67 +21 +97 +51 +127 +81 1.0 0 0 +30 +30 +60 +60 0.9 -5 -14 +25 +16 +55 +46 0.8 -13 -31 +17 -1 +47 +29 0.7 -22 -54 +8 -24 +38 +6 0.6 -34 -83 -4 -53 +26 -23 0.5 -60 -125 -30 -95 0 -65 0.4 -100 -188 -70 -158 -40 -128 0.3 -168 -292 -138 -262 -108 -232 0.25 -200 -375 -170 -345 -140 -315 0.2 -325 -500 -295 -470 -265 -440 0.15 -517 -708 -487 -678 -457 -648 0.1 -1000 -1125 -970 -1095 -940 -1065 Units ps ps ps ps ps ps ps ps ps ps ps ps ps ps ps ps ps ps Notes 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 NOTE 10: The maximum limit for this parameter is not a device limit. The device will operate with a greater value for this parameter, but system performance (bus turnaround) will degrade accordingly. NOTE 11: MIN (tCL, tCH) refers to the smaller of the actual clock LOW time and the actual clock HIGH time as provided to the device (i.e. this value can be greater than the minimum specification limits for tCL and tCH). NOTE 12: tQH = tHP – tQHS, where: tHP = minimum half clock period for any given cycle and is defined by clock HIGH or clock LOW (tCH, tCL). tQHS accounts for: 1) The pulse duration distortion of on-chip clock circuits; and 2) The worst case push-out of DQS on one transition followed by the worst case pull-in of DQ on the next transition, both of which are, separately, due to data pin skew and output pattern effects, and p-channel to n-channel variation of the output drivers. NOTE 13: tDQSQ: Consists of data pin skew and output pattern effects, and p-channel to n-channel variation of the output drivers as well as output slew rate mismatch between DQS / DQS# and associated DQ in any given cycle. NOTE 14: tDAL = WR + RU{ tRP[ns] / tCK[ns] }, where RU stands for round up.WR refers to the tWR parameter stored in the MRS. For tRP, if the result of the division is not already an integer, round up to the next highest integer. tCK refers to the application clock period. NOTE 15: The clock frequency is allowed to change during self–refresh mode or precharge power-down mode. In case of clock frequency change during precharge power-down. NOTE 16: ODT turn on time min is when the device leaves high impedance and ODT resistance begins to turn on. ODT turn on time max is when the ODT resistance is fully on. Both are measured from tAOND, which is interpreted differently per speed bin. For DDR2-667/800/1066, tAOND is 2 clock cycles after the clock edge that registered a first ODT HIGH counting the actual input clock edges. Rev. 1.0 30 May /2015 EtronTech EM68A16CBQC NOTE 17: ODT turn off time min is when the device starts to turn off ODT resistance. ODT turn off time max is when the bus is in high impedance. Both are measured from tAOFD, which is interpreted differently per speed bin. For DDR2-667/800/1066, if tCK(avg) = 3 ns is assumed, tAOFD is 1.5 ns (= 0.5 x 3 ns) after the second trailing clock edge counting from the clock edge that registered a first ODT LOW and by counting the actual input clock edges. NOTE 18: tHZ and tLZ transitions occur in the same access time as valid data transitions. These parameters are referenced to a specific voltage level which specifies when the device output is no longer driving (tHZ), or begins driving (tLZ). NOTE 19: 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). The actual voltage measurement points are not critical as long as the calculation is consistent. NOTE 20: Input waveform timing tDS with differential data strobe enabled MR[bit10]=0, is referenced from the input signal crossing at the VIH(ac) level to the differential data strobe crosspoint for a rising signal, and from the input signal crossing at the VIL(ac) level to the differential data strobe crosspoint for a falling signal applied to the device under test. DQS, DQS# signals must be monotonic between VIL(dc)max and VIH(dc)min. NOTE 21: Input waveform timing tDH with differential data strobe enabled MR [bit10] =0, is referenced from the differential data strobe crosspoint to the input signal crossing at the VIH (dc) level for a falling signal and from the differential data strobe crosspoint to the input signal crossing at the VIL(dc) level for a rising signal applied to the device under test. DQS, DQS# signals must be monotonic between VIL (dc) max and VIH (dc) min. NOTE 22: Input waveform timing is referenced from the input signal crossing at the VIH (ac) level for a rising signal and VIL (ac) for a falling signal applied to the device under test. NOTE 23: Input waveform timing is referenced from the input signal crossing at the VIL (dc) level for a rising signal and VIH (dc) for a falling signal applied to the device under test. NOTE 24: tWTR is at lease two clocks (2 x tCK ) independent of operation frequency. NOTE 25: tCKEmin of 3 clocks means CKE must be registered on three consecutive positive clock edges. CKE must remain at the valid input level the entire time it takes to achieve the 3 clocks of registration. Thus, after any CKE transition, CKE may not transition from its valid level during the time period of tIS + 2 x tCK + tIH. NOTE 26: If tDS or tDH is violated, data corruption may occur and the data must be re-written with valid data before a valid READ can be executed. NOTE 27: These parameters are measured from a command/address signal (CKE, CS#, RAS#, CAS#, WE#, ODT, BA0, A0, A1, etc.) transition edge to its respective clock signal (CK/CK#) crossing. The spec values are not affected by the amount of clock jitter applied (i.e. tJIT(per), tJIT(cc), etc.), as the setup and hold are relative to the clock signal crossing that latches the command/address. That is, these parameters should be met whether clock jitter is present or not. NOTE 28: These parameters are measured from a data strobe signal (LDQS/UDQS) crossing to its respective clock signal (CK/CK#) crossing. The spec values are not affected by the amount of clock jitter applied (i.e. tJIT(per), tJIT(cc), etc.), as these are relative to the clock signal crossing. That is, these parameters should be met whether clock jitter is present or not. NOTE 29: These parameters are measured from a data signal ((L/U) DM, (L/U) DQ0, (L/U) DQ1, etc.) transition edge to its respective data strobe signal (LDQS/UDQS/LDQS#/UDQS#) crossing. NOTE 30: For these parameters, the DDR2 SDRAM device is characterized and verified to support tnPARAM = RU{tPARAM / tCK(avg)}, which is in clock cycles, assuming all input clock jitter specifications are satisfied. NOTE 31: tDAL [tCK] = WR [tCK] + tRP [tCK] = WR + RU {tRP [ps] / tCK(avg) [ps] }, where WR is the value programmed in the mode register set. NOTE 32: New units, ‘tCK(avg)’ is introduced in DDR2-667, DDR2-800 and DDR2-1066. Unit ‘tCK (avg)’ represents the actual tCK(avg) of the input clock under operation. NOTE 33: Input clock jitter spec parameter. These parameters and the ones in the table below are referred to as 'input clock jitter spec parameters' and these parameters apply to DDR2-667, DDR2-800 and DDR21066 only. The jitter specified is a random jitter meeting a Gaussian distribution. Rev. 1.0 31 May /2015 EtronTech EM68A16CBQC Table 30. Input clock jitter spec parameter Parameter Symbol Min. -90 Clock period jitter tJIT (per) Clock period jitter during DLL tJIT (per,lck) locking period Cycle to cycle clock period jitter tJIT (cc) Cycle to cycle clock period jitter tJIT (cc,lck) during DLL locking period Cumulative error across 2 cycles tERR (2per) Cumulative error across 3 cycles tERR (3per) Cumulative error across 4 cycles tERR (4per) Cumulative error across 5 cycles tERR (5per) Cumulative error across n cycles, tERR (6-10per) n=6...10, inclusive Cumulative error across n cycles, tERR (11-50per) n=11...50, inclusive Duty cycle jitter tJIT (duty) -18I Max. 90 Min. -100 -25I Max. 100 -3I Min. -125 Max. 125 Unit Note ps 33 -80 80 -80 80 -100 100 ps 33 -180 180 -200 200 -250 250 ps 33 -160 160 -160 160 -200 200 ps 33 -132 -157 -175 132 157 175 -150 -175 -200 150 175 200 -175 -225 -250 175 225 250 ps ps ps 33 33 33 -188 188 -200 200 -250 250 ps 33 -250 250 -300 300 -350 350 ps 33 -425 425 -450 450 -450 450 ps 33 -75 75 -100 100 -125 125 ps 33 Definitions: - tCK(avg) tCK(avg) is calculated as the average clock period across any consecutive 200 cycle window. ⎡ ⎤ N t CK ( avg ) = ⎢∑ t CK ⎥ / N ⎣ j =1 j ⎦ where N=200 - tCH(avg) and tCL(avg) tCH(avg) is defined as the average HIGH pulse width, as calculated across any consecutive 200 HIGH pulses. ⎡ ⎤ t CH ( avg ) = ⎢∑ t CH ⎥ / ( N × t CK ( avg ) ) N ⎣ j =1 j ⎦ where N=200 tCL(avg) is defined as the average LOW pulse width, as calculated across any consecutive 200 LOW pulses. ⎡N ⎤ avg / N × t CK ( avg ) = t CL ( ) ⎢⎣∑ t CL j ⎥ j =1 ⎦ ( ) where N=200 tJIT (duty) is defined as the cumulative set of tCH jitter and tCL jitter. tCH jitter is the largest deviation of any single tCH from tCH(avg). tCL jitter is the largest deviation of any single tCL from tCL(avg). - tJIT(duty) = Min/max of {tJIT(CH), tJIT(CL)} where, tJIT(CH) = {tCHi- tCH(avg) where i=1 to 200} tJIT(CL) = {tCLi- tCL(avg) where i=1 to 200} - tJIT(per), tJIT(per,lck) tJIT(per) is defined as the largest deviation of any single tCK from tCK(avg). tJIT(per) = Min/max of {tCKi- tCK(avg) where i=1 to 200} tJIT(per) defines the single period jitter when the DLL is already locked. tJIT(per,lck) uses the same definition for single period jitter, during the DLL locking period only. tJIT(per) and tJIT(per,lck) are not guaranteed through final production testing. Rev. 1.0 32 May /2015 EtronTech EM68A16CBQC - tJIT(cc), tJIT(cc,lck) tJIT(cc) is defined as the difference in clock period between two consecutive clock cycles: tJIT(cc) = Max of |tCKi+1 – tCKi| tJIT(cc) defines the cycle to cycle jitter when the DLL is already locked. tJIT(cc,lck) uses the same definition for cycle to cycle jitter, during the DLL locking period only. tJIT(cc) and tJIT(cc,lck) are not guaranteed through final production testing. - tERR(2per), tERR (3per), tERR (4per), tERR (5per), tERR (6-10per) and tERR (11-50per) tERR is defined as the cumulative error across multiple consecutive cycles from tCK(avg). ⎡ i +N −1 ⎤ t ERR (nper ) = ⎢ ∑ t CK ⎥ − ( N × t CK ( avg ) ) ⎣ j =1 j ⎦ ⎧n=2 ⎪ ⎪n=3 ⎪ ⎪n=4 where ⎨ ⎪n=5 ⎪ ⎪6 ≤ n ≤ 10 ⎪11 ≤ n ≤ 50 ⎩ for for for for for for ( 2per ) ( 3 per ) ERR ( 4 per ) ERR ( 5 per ) ERR ( 6 − 10 per ) ERR (11 − 50 per ) ERR t t t t t t ERR NOTE 34: These parameters are specified per their average values, however it is understood that the following relationship between the average timing and the absolute instantaneous timing holds at all times. (Min andmax of SPEC values are to be used for calculations in the table below.) Table 31. Absolute clock period average values Parameter Symbol Min. Max. tCK(avg),min + tJIT(per),min tCK(avg),max + tJIT(per),max tCK Absolute clock period (abs) tCH tCH(avg),min * tCK(avg),min + tCH(avg),max * tCK(avg),max + Absolute clock HIGH pulse width (abs) tJIT(duty),min tJIT(duty),max tCL(avg),min * tCK(avg),min + tCL(avg), max * tCK(avg),max + tCL Absolute clock LOW pulse width (abs) tJIT(duty),min tJIT(duty), max Unit ps ps ps NOTE 35: tHP is the minimum of the absolute half period of the actual input clock. tHP is an input parameter but not an input specification parameter. It is used in conjunction with tQHS to derive the DRAM output timing tQH. The value to be used for tQH calculation is determined by the following equation; tHP = Min ( tCH(abs), tCL(abs) ), where, tCH(abs) is the minimum of the actual instantaneous clock HIGH time; tCL(abs) is the minimum of the actual instantaneous clock LOW time; NOTE 36: tQHS accounts for: 1) The pulse duration distortion of on-chip clock circuits, which represents how well the actual tHP at the input is transferred to the output; and 2) The worst case push-out of DQS on one transition followed by the worst case pull-in of DQ on the next transition, both of which are independent of each other, due to data pin skew, output pattern effects, and p-channel to n-channel variation of the output drivers NOTE 37: tQH = tHP – tQHS, where: tHP is the minimum of the absolute half period of the actual input clock; and tQHS is the specification value under the max column. {The less half-pulse width distortion present, the larger the tQH value is; and the larger the valid data eye will be.} NOTE 38: When the device is operated with input clock jitter, this parameter needs to be derated by the actual tERR(6-10per) of the input clock. (output deratings are relative to the SDRAM input clock.) Rev. 1.0 33 May /2015 EtronTech EM68A16CBQC NOTE 39: When the device is operated with input clock jitter, this parameter needs to be derated by the actual tJIT(per) of the input clock. (output deratings are relative to the SDRAM input clock.) NOTE 40: When the device is operated with input clock jitter, this parameter needs to be derated by the actual tJIT(duty) of the input clock. (output deratings are relative to the SDRAM input clock.) NOTE 41: When the device is operated with input clock jitter, this parameter needs to be derated by { tJIT(duty),max - tERR(6-10per),max } and { - tJIT(duty),min - tERR(6-10per),min } of the actual input clock. (output deratings are relative to the SDRAM input clock.) NOTE 42: For tAOFD of DDR2-667/800/1066, the 1/2 clock of tCK in the 2.5 x tCK assumes a tCH(avg), average input clock HIGH pulse width of 0.5 relative to tCK(avg). tAOF,min and tAOF,max should each be derated by the same amount as the actual amount of tCH(avg) offset present at the DRAM input with respect to 0.5. NOTE 43: If refresh timing is violated, data corruption may occur and the data must be re-writtern with valid data before a valid READ can be executed. Rev. 1.0 34 May /2015 EtronTech EM68A16CBQC Timing Waveforms Figure 7. Initialization sequence after power-up tCH tCL CK CK# tIS CKE tIS ODT Command PRE ALL NOP tRP 400ns tMRD DLL ENABLE PRE ALL MRS EMRS tMRD REF REF tRP tRFC tRFC DLL RESET MRS EMR S EMRS tMRD min 200 Cycle Follow OCD Flowchart ANY CMD t OIT OCD CAL.MOD E EXIT OCD Default NOTE 1: To guarantee ODT off, VREF must be valid and a LOW level must be applied to the ODT pin. Figure 8. OCD drive mode OCD calibration mode exit Enter Drive mode CMD EMRS NOP NOP NOP EMRS CK# CK DQS DQS# Hi-Z DQS HIGH & DQS# LOW for Drive(1), DQS LOW & DQS# HIGH for Drive(0) Hi-Z DQs HIGH for Drive(1) DQ DQs LOW for Drive(0) tOIT tOIT NOTE : Drive mode, both Drive(1) and Drive(0), is used for controllers to measure DDR2 SDRAM Driver impedance.In this mode, all outputs are driven out tOIT after "enter drive mode" command and all output drivers are turned-off tOIT after "OCD calibration mode exit" command. Rev. 1.0 35 May /2015 EtronTech EM68A16CBQC Figure 9. OCD adjust mode OCD calibration mode exit OCD adjust mode CMD EMRS NOP NOP NOP NOP EMRS NOP NOP CK# CK WL DQS_in tDS tDH VIH(ac) DQ_in WR DQS# VIH(dc) DT0 DT1 DT2 DT3 VIL(ac) VIL(dc) DM NOTE 1: For proper operation of adjust mode, WL = RL - 1 = AL + CL - 1tCK and tDS /tDH should be met as shown in the figure. NOTE 2: For input data pattern for adjustment, DT0-DT3 is a fixed order and is not affected by burst type (i.e., sequential or interleave) Figure 10. ODT update delay timing-tMOD CMD EMRS NOP NOP NOP NOP NOP CK# CK ODT tIS tAOFD Rtt Old setting tMOD, min tMOD, max Updating New setting NOTE 1: To prevent any impedance glitch on the channel, the following conditions must be met: - tAOFD must be met before issuing the EMRS command. - ODT must remain LOW for the entire duration of tMOD window, until tMOD, max is met. then the ODT is ready for normal operation with the new setting, and the ODT signal may be raised again to turned on the ODT. NOTE 2: EMRS command directed to EMR(1), which updates the information in EMR(1)[A6,A2], i.e. Rtt (Nominal). NOTE 3: "setting" in this diagram is the Register and I/O setting, not what is measured from outside. Rev. 1.0 36 May /2015 EtronTech EM68A16CBQC Figure 11. ODT update delay timing-tMOD, as measured from outside CK# CK CMD EMRS NOP NOP ODT NOP NOP tIS tAOFD Rtt NOP tAOND tMOD, max New setting Old setting NOTE 1: EMRS command directed to EMR(1), which updates the information in EMR(1)[A6,A2], i.e. Rtt (Nominal). NOTE 2: "setting" in this diagram is measured from outside. Figure 12. ODT timing for active standby mode T0 T1 T3 T2 T4 T5 T6 CK# CK tIS CKE tIS tIS VIH(ac) ODT Internal Term Res. VIL(ac) tAOND tAOFD RTT tAON,min tAON,max Rev. 1.0 37 tAOF,min tAOF,max May /2015 EtronTech EM68A16CBQC Figure 13. ODT timing for power-down mode T0 T1 T3 T2 T4 T5 T6 CK# CK CKE tIS tIS VIH(AC) VIL(AC) ODT tAOFPD,max tAOFPD,min Internal Term Res. RTT tAONPD,min tAONPD,max Figure 14. ODT timing mode switch at entering power-down mode T-5 CK# T-4 T-3 T-2 CK T-1 tANPD T0 T1 T2 T3 T4 tIS CKE Entering Slow Exit Active Power Down Mode or Precharge Power Down Mode. ODT tIS VIL(ac) tAOFD Internal Term Res. Active & Standby mode timings to be applied. RTT tIS ODT VIL(ac) Power Down mode timings to be applied. tAOFPD max Internal Term Res. RTT tIS VIH(ac) ODT tAOND RTT Internal Term Res. VIH(ac) ODT tIS tAONPD max RTT Internal Term Res. Rev. 1.0 Active & Standby mode timings to be applied. 38 Power Down mode timings to be applied. May /2015 EtronTech EM68A16CBQC Figure 15. ODT timing mode switch at exit power-down mode T0 CK# CK VIH(ac) T1 T4 T5 T6 T7 T8 T9 T10 T11 tAXPD tIS CKE Exiting from Slow Active Power Down Mode or Precharge power Down Mode. tIS ODT Active & Standby mode timings to be applied. VIL(ac) tAOFD Internal Term Res. RTT tIS ODT Power Down mode timings to be applied. VIL(ac) tAOFPD max Internal Term Res. RTT tIS Active & Standby mode timings to be applied. VIH(ac) ODT tAOND RTT Internal Term Res. VIH(ac) Power Down mode timings to be applied. tIS ODT tAONPD max Internal Term Res. RTT Figure 16. Bank activate command cycle ( tRCD=3, AL=2, tRP=3, tRRD=2, tCCD=2) T0 T1 T3 T2 Tn Tn+1 Tn+2 Tn+3 CK# CK ADDRESS Internal RAS# - CAS# delay (>=tRCD min) Bank A Row Addr. tRCD = 1 Bank A Col. Addr. Bank A Activate Bank A Addr. Bank B Addr. Bank A Row Addr. Bank A Precharge Bank B Precharge Bank A Activate CAS# - CAS# delay time (tCCD) Additive latency delay (AL) Read Begins RAS# - RAS# delay time (>=tRRD) COMMAND Bank B Col. Addr Bank B Row Addr. Bank A Post CAS# Read Bank B Activate Bank B Post CAS# Read Bank precharge time (>=tRP) Bank Active (>=tRAS) RAS# Cycle time (>=tRC) Rev. 1.0 39 May /2015 EtronTech EM68A16CBQC Figure 17.1. Posted CAS# operation: AL=2 Read followed by a write to the same bank -1 0 1 2 Active A-Bank Read A-Bank 3 4 5 6 7 8 9 10 11 12 11 12 CK# CK CMD Write A-Bank AL=2 WL=RL-1=4 CL=3 DQS DQS# >=tRCD RL=AL+CL=5 DQ Dout 0 Dout 1 Dout 2 Dout 3 Din 0 Din 1 Din 2 Din 3 [ AL=2 and CL=3, RL= (AL+CL)=5, WL= (RL-1)=4, BL=4] Figure 17.2. Posted CAS# operation: AL=0 Read followed by a write to the same bank -1 0 1 2 3 4 5 6 7 8 9 10 CK# CK AL=0 CMD Active A-Bank Write A-Bank Read A-Bank CL=3 DQS DQS# WL=RL-1=2 >=tRCD RL=AL+CL=3 DQ Dout 0 Dout 1 Dout 2 Dout 3 Din 0 Din 1 Din 2 Din 3 [ AL=0 and CL=3, RL= (AL+CL)=3, WL= (RL-1)=2, BL=4] Rev. 1.0 40 May /2015 EtronTech EM68A16CBQC Figure 18. Data output (read) timing CK tCL tCH CK# CK DQS# DQS DQS# DQS tRPRE DQ tRPST Q tDQSQ max Q Q Q tDQSQ max tQH tQH Figure 19.1. Burst read operation: RL=5 (AL=2, CL=3, BL=4) CK# CK CMD T0 T1 Posted CAS# READ A NOP T2 NOP T3 T4 NOP T5 NOP T6 NOP T7 NOP NOP T8 NOP =< tDQSCK DQS DQS# AL=2 CL=3 RL=5 DQs Dout A0 Dout A1 Dout A2 Dout A3 Figure 19.2. Burst read operation: RL=3 (AL=0 and CL=3, BL=8) CK# CK CMD T0 READ A DQS DQS# T1 NOP T2 NOP T3 T4 NOP T5 NOP T6 NOP T7 NOP NOP T8 NOP =< tDQSCK CL=3 RL=3 DQs Rev. 1.0 Dout A0 Dout A1 Dout A2 Dout A3 41 Dout A4 Dout A5 Dout A6 Dout A7 May /2015 EtronTech EM68A16CBQC Figure 20. Burst read followed by burst write: RL=5, WL= (RL-1) =4, BL=4 T0 CK# CK CMD T1 Post CAS# READ A Tn-1 NOP Tn Tn+1 Post CAS# WRITE A NOP Tn+2 NOP Tn+3 NOP Tn+4 NOP Tn+5 NOP NOP tRTW (Read to Write turn around time) DQS DQS# RL=5 WL = RL-1 = 4 DQs Dout A0 Dout A1 Dout A2 Dout A3 Din A0 Din A1 Din A2 Din A3 NOTE : The minimum time from the burst read command to the burst write command is defined by a read-to-writeturn-around-time, which is 4 clocks in case of BL = 4 operation, 6 clocks in case of BL = 8 operation. Figure 21. Seamless burst read operation: RL=5, AL=2, CL=3, BL=4 T0 CK# CK CMD T1 Post CAS# READ A NOP T2 T3 Post CAS# READ B T4 NOP NOP T5 T6 NOP T7 NOP T8 NOP NOP DQS DQS# AL=2 CL=3 RL=5 DQs Dout A0 Dout A1 Dout A2 Dout A3 Dout B0 Dout B1 Dout B2 NOTE : The seamless burst read operation is supported by enabling a read command at every other clock for BL = 4 operation, and every 4 clock for BL =8 operation. This operation is allowed regardless of same or different banks as long as the banks are activated. Rev. 1.0 42 May /2015 EtronTech EM68A16CBQC Figure 22. Read burst interrupt timing: (CL=3, AL=0, RL=3, BL=8) CK# CK CMD Read A NOP NOP Read B NOP NOP NOP NOP NOP NOP DQS DQS# DQs A0 A1 A2 A3 B0 B1 B2 B3 B4 B5 B6 B7 NOTE 1: Read burst interrupt function is only allowed on burst of 8. Burst interrupt of 4 is prohibited. NOTE 2: Read burst of 8 can only be interrupted by another Read command. Read burst interruption by Write command or Precharge command is prohibited. NOTE 3: Read burst interrupt must occur exactly two clocks after previous Read command. Any other Read burst interrupt timings are prohibited. NOTE 4: Read burst interruption is allowed to any bank inside DRAM. NOTE 5: Read burst with Auto Precharge enabled is not allowed to interrupt. NOTE 6: Read burst interruption is allowed by another Read with Auto Precharge command. NOTE 7: All command timings are referenced to burst length set in the mode register. They are not referenced to actual burst. For example, Minimum Read to Precharge timing is AL+BL/2 where BL is the burst length set in the mode register and not the actual burst (which is shorter because of interrupt). Figure 23. Data input (write) timing tDQSH DQS# tDQSL DQS DQS# DQS tWPRE DQ tWPSL VIH(ac) D VIL(ac) tDS DM Rev. 1.0 VIH(dc) D D VIL(dc) tDH tDS tDH VIH(dc) VIH(ac) DMin D DMin DMin VIL(ac) 43 DMin VIL(dc) May /2015 EtronTech EM68A16CBQC Figure 24.1. Burst write operation: RL=5 (AL=2, CL=3), WL=4, BL=4 CK# CK CMD T0 T1 Posted CAS# WRITE A T2 NOP T3 NOP T4 NOP Case 1: with tDQSS (max) DQS DQS# T5 NOP NOP tDQSS tDSS tDQSS T6 NOP tDSS NOP Tn Precharge Completion of the Burst Write WL = RL-1 =4 >=tWR DQs DNA0 Case 2: with tDQSS (min) DQS DQS# T7 tDQSS tDSH DNA1 DNA2 DNA3 tDQSS tDSH >=tWR WL = RL-1 =4 DQs DNA0 DNA1 DNA2 DNA3 Figure 24.2. Burst write operation: RL=3 (AL=0, CL=3), WL=2, BL=4 CK# CK T0 CMD T1 WRITE A NOP T2 T3 NOP T4 NOP NOP =tWR DNA1 Tm+1 NOP Precharge Tn Bank A Activate Completion of the Burst Write WL = RL-1 =2 DNA0 Tm >=tRP DNA2 DNA3 44 May /2015 EtronTech EM68A16CBQC Figure 25. Burst write followed by burst read: RL=5 (AL=2, CL=3, WL=4, tWTR=2, BL=4) CK# T0 T1 T2 T3 T4 T5 T6 T7 T8 T9 CK Write to Read = CL-1+BL/2+tWTR CKE DQS DQS# NOP NOP NOP Post CAS# READ A NOP NOP NOP NOP NOP DQS# DQS WL = RL-1 = 4 AL=2 CL=3 RL=5 >=tWTR DQ DNA0 DNA1 DNA2 DNA3 DOUT A0 NOTE : The minimum number of clock from the burst write command to the burst read command is [CL-1 + BL/2 + tWTR]. This tWTR is not a write recovery time (tWR) but the time required to transfer the 4 bit write data from the input buffer into sense amplifiers in the array. tWTR is defined in the timing parameter table of this standard. Figure 26. Seamless burst write operation RL=5, WL=4, BL=4 CK# T0 T1 T2 T3 T4 T5 T6 T7 T8 CK CMD DQS DQS# Post CAS# Write A NOP Post CAS# Write B NOP NOP NOP NOP NOP NOP DQS# DQS WL = RL-1 = 4 DQ DNA0 DNA1 DNA2 DNA3 DNB0 DNB1 DNB2 DNB3 NOTE : The seamless burst write operation is supported by enabling a write command every other clock for BL= 4 operation, every four clocks for BL = 8 operation. This operation is allowed regardless of same or different banks as long as the banks are activated. Rev. 1.0 45 May /2015 EtronTech EM68A16CBQC Figure 27. Write burst interrupt timing: (CL=3, AL=0, RL=3, WL=2, BL=8) CK# CK CMD NOP Write A NOP Write B NOP NOP NOP NOP NOP NOP DQS DQS# DQs A0 A1 A2 A3 B0 B1 B2 B3 B4 B5 B6 B7 NOTE 1: Write burst interrupt function is only allowed on burst of 8. Burst interrupt of 4 is prohibited. NOTE 2: Write burst of 8 can only be interrupted by another Write command. Write burst interruption by Read command or Precharge command is prohibited. NOTE 3: Write burst interrupt must occur exactly two clocks after previous Write command. Any other Write burst interrupt timings are prohibited. NOTE 4: Write burst interruption is allowed to any bank inside DRAM. NOTE 5: Write burst with Auto Precharge enabled is not allowed to interrupt. NOTE 6: Write burst interruption is allowed by another Write with Auto Precharge command. NOTE 7: All command timings are referenced to burst length set in the mode register. They are not referenced to actual burst. For example, minimum Write to Precharge timing is WL + BL/2 + tWR where tWR starts with the rising clock after the uninterrupted burst end and not from the end of actual burst end. Rev. 1.0 46 May /2015 EtronTech EM68A16CBQC Figure 28. Write data mask Data Mask Timing DQS DQS# DQ DM Data Mask Function, WL=3, AL=0, BL=4 shown VIH(ac)VIH(dc) VIH(ac)VIH(dc) VIL(ac)VIL(dc) VIL(ac)VIL(dc) tDS tDH tDS tDH Case 1: min tDQSS CK# CK tWR COMMAND DQS DQS# Write WL tDQSS DQ DM Case 2: max tDQSS tDQSS DQS DQS# DQ DM Rev. 1.0 47 May /2015 EtronTech EM68A16CBQC Figure 29.1. Burst read operation followed by precharge: (RL=4, AL=1, CL=3, BL=4, tRTP ≦2 clocks) T0 CK# T1 T2 T3 T4 T5 T6 T7 T8 CK Post CAS# Read A CMD NOP NOP NOP Precharge NOP Bank A Active NOP NOP AL+BL'/2 clks DQS DQS# AL=1 CL=3 >=tRP RL=4 DQ DOUTA0 DOUTA1 DOUTA2 DOUTA3 >=tRAS >=tRTP CL=3 Figure 29.2.Burst read operation followed by precharge: (RL=4, AL=1, CL=3, BL=8, tRTP≦2 clocks) CK# CK T0 CMD DQS DQS# DQ's T1 Post CAS# READ A T2 NOP T3 NOP T4 NOP NOP T5 T6 T7 NOP Precharge A T8 NOP NOP AL + BL/2 clks CL = 3 AL = 1 RL= 4 DOUT A0 DOUT A1 DOUT A2 DOUT A3 DOUT A4 DOUT A5 DOUT A6 DOUT A7 >=tRTP First 4-bit prefetch Rev. 1.0 Second 4-bit prefetch 48 May /2015 EtronTech EM68A16CBQC Figure 29.3. Burst read operation followed by precharge: (RL=5, AL=2, CL=3, BL=4, tRTP≦2 clocks) T0 T1 T2 T3 T4 T5 T6 T7 T8 CK# CK Post CAS# READ A CMD NOP NOP NOP NOP Precharge A NOP Bank A Activate NOP AL + BL/2 clks DQS DQS# CL = 3 AL = 2 >=tRP RL= 5 DOUT A0 DQ's >=tRAS DOUT A1 DOUT A2 DOUT A3 CL = 3 >=tRTP Figure 29.4. Burst read operation followed by precharge: (RL=6, AL=2, CL=4, BL=4, tRTP≦2 clocks) T0 T1 T2 T3 T4 T5 T6 T7 T8 CK# CK CMD Post CAS# READ A NOP NOP NOP Precharge A NOP NOP Bank A Activate NOP AL + BL/2 clks DQS DQS# CL = 4 AL = 2 >=tRP RL= 6 DOUT A0 DQ's >=tRAS DOUT A1 DOUT A2 DOUT A3 CL = 4 >=tRTP Rev. 1.0 49 May /2015 EtronTech EM68A16CBQC Figure 29.5. Burst read operation followed by precharge: (RL=4, AL=0, CL=4, BL=8, tRTP>2 clocks) T0 CK# T1 T2 T3 T4 T5 T6 T7 T8 CK Post CAS# READ A CMD NOP NOP NOP NOP NOP Precharge A NOP Bank A Activate AL + 2 + max( tRTP, 2 tCK)* DQS DQS# CL = 4 AL = 0 >=tRP RL= 4 DQ's DOUT A0 >=tRAS DOUT A1 DOUT A2 DOUT A3 DOUT A4 DOUT A5 DOUT A6 DOUT A7 >=tRTP First 4-bit prefetch Second 4-bit prefetch *: rounded to next integer. Figure 30.1. Burst write operation followed by precharge: WL= (RL-1) =3 CK# T0 T1 T2 T3 T4 T5 T6 T7 T8 CK CMD Post CAS# Write A NOP NOP NOP NOP NOP NOP NOP Precharge A Completion of the Burst Write DQS DQS# DQ's Rev. 1.0 >=tWR WL= 3 DNA0 DNA1 50 DNA2 DNA3 May /2015 EtronTech EM68A16CBQC Figure 30.2. Burst write followed by precharge: WL= (RL-1) =4 T0 CK# T1 T2 T3 T4 T5 T6 T7 T9 CK Post CAS# Write A CMD NOP NOP NOP NOP NOP NOP NOP Precharge A Completion of the Burst Write >=tWR DQS DQS# WL= 4 DQ's DNA0 DNA1 DNA2 DNA3 Figure 31.1. Burst read operation with auto precharge: (RL=4,AL=1, CL=3, BL=8, tRTP≦2 clocks) T0 CK# CK T1 Post CAS# READ A CMD T2 NOP NOP Autoprecharge DQS DQS# DQ's T3 T4 NOP T5 NOP T6 NOP NOP T8 Bank A Activate NOP >= tRP AL + BL/2 clks AL = 1 T7 CL = 3 RL= 4 >=tRTP DOUT A0 DOUT A1 DOUT A2 DOUT A3 DOUT A4 DOUT A5 DOUT A6 DOUT A7 tRTP First 4-bit prefetch Rev. 1.0 Second 4-bit prefetch 51 Precharge begins here May /2015 EtronTech EM68A16CBQC Figure 31.2. Burst read operation with auto precharge: (RL=4, AL=1, CL=3, BL=4, tRTP>2 clocks) T0 CK# T1 T2 T3 T4 T5 T6 T7 T8 CK Post CAS# READ A CMD NOP NOP NOP NOP NOP Bank A Activate NOP >= AL+tRTP+tRP Autoprecharge DQS DQS# NOP AL= 1 CL= 3 RL= 4 DQ's DoutA0 DoutA1 DoutA2 DoutA3 tRTP tRP First 4-bit prefetch Precharge begins here Figure 31.3. Burst read operation with auto precharge followed by activation to the same bank (tRC Limit): RL=5(AL=2, CL=3, internal tRCD=3, BL=4,tRTP≦2 clocks) T0 CK# CK T1 T2 T3 T4 T5 T6 T7 T8 A10= 1 CMD DQS DQS# Post CAS# READ A NOP NOP NOP NOP NOP NOP Bank A Activate >=tRAS(min) Auto Precharge Begins AL= 2 CL= 3 RL= 5 DQ's >=tRP DoutA0 DoutA1 DoutA2 DoutA3 CL=3 >= tRC Rev. 1.0 NOP 52 May /2015 EtronTech EM68A16CBQC Figure 31.4. Burst read operation with auto precharge followed by an activation to the same bank (tRP Limit): (RL=5 (AL=2, CL=3, internal tRCD=3, BL=4, tRTP≦2 clocks) T0 CK# CK T1 T2 T3 T4 T5 T6 T7 T8 A10= 1 Post CAS# READ A CMD NOP NOP NOP >=tRAS(min) NOP NOP Bank A Activate NOP NOP Auto Precharge Begins DQS DQS# AL= 2 >= tRP CL= 3 RL= 5 DQ's DoutA0 DoutA1 DoutA2 DoutA3 CL=3 >= tRC Figure 32.1. Burst write with auto-precharge (tRC Limit): WL=2, WR=2, BL=4, tRP=3 T0 CK# T1 T2 T3 T4 T5 T6 T7 Tm CK A10 = 1 CMD Post CAS# WRA Bank A NOP NOP NOP NOP NOP NOP NOP Bank A Active Completion of the Burst Write DQS DQS# DQ's Rev. 1.0 Auto Precharge Begins >=WR WL= RL-1=2 DNA0 DNA1 >=tRP DNA2 DNA3 >=tRC 53 May /2015 EtronTech EM68A16CBQC Figure 32.2. Burst write with auto-precharge (WR+tRP): WL=4, WR=2, BL=4, tRP=3 T0 CK# T3 T4 T5 T6 T7 T8 T9 T12 CK A10 = 1 CMD Post CAS# WRA Bank A NOP NOP NOP NOP NOP NOP NOP Bank A Active Completion of the Burst Write Auto Precharge Begins DQS DQS# >=WR >=tRP WL= RL-1=4 DQ's DNA0 DNA1 DNA2 DNA3 >=tRC Figure 33. Refresh command T0 T1 T2 T3 Tm Tn Tn+1 CK# CK HIGH CKE CMD Rev. 1.0 >=tRP Precharge NOP >=tRFC NOP REF >=tRFC REF 54 NOP ANY May /2015 EtronTech EM68A16CBQC Figure 34. Self refresh operation T0 CK# tCH tCK T1 T2 T3 T4 T5 T6 Tm Tn tCL CK >=tXSNR tRP* >=tXSRD CKE VIH(ac) VIL(ac) tAOFD ODT tIS tIS VIL(ac) tIS tIS tIH tIH tIS VIH(ac) Self VIH(dc) VIL(ac) Refresh VIL(dc) CMD tIH NOP NOP NOP Valid NOTE 1 Device must be in the "All banks idle" state prior to entering Self Refresh mode. NOTE 2 ODT must be turned off tAOFD before entering Self Refresh mode, and can be turned on again when tXSRD timing is satisfied. NOTE 3 tXSRD is applied for Read or a Read with autoprecharge command. tXSNR is applied for any command except a Read or a Read with autoprecharge command. Figure 35. Basic power down entry and exit timing diagram CK CK# CKE Command tIH tIS VALID tIH NOP tIS NOP NOP tCKE min tIS tIH VALID VALID or NOP tXP, tXARD tXARDS Exit Power-Down mode Enter Power-Down mode tIH tCKE(min) Don't Care Figure 36.1.CKE intensive environment CK# CK tCKE tCKE CKE tCKE tCKE NOTE: DRAM guarantees all AC and DC timing & voltage specifications and proper DLL operation with intensive CKE operation Rev. 1.0 55 May /2015 EtronTech EM68A16CBQC Figure 36.2.CKE intensive environment CK# CK CKE tCKE tCKE tCKE tXP CMD tCKE tXP REF REF tREFI = 7.8 µs NOTE: The pattern shown above can repeat over a long period of time. With this pattern, DRAM guarantees all AC and DC timing & voltage specifications and DLL operation with temperature and voltage drift Figure 37. Read to power-down entry T0 T1 T2 Tx Tx+1 Tx+2 Tx+3 Tx+4 Tx+5 Tx+6 Tx+7 Tx+8 Tx+9 Tx+8 Tx+9 CK# CK CMD Read operation starts with a read command and RD CKE should be kept HIGH until the end of burst operation BL=4 CKE AL+CL Q DQ Q Q tIS Q DQS DQS# T0 T1 T2 Tx Tx+1 Tx+2 Tx+3 Tx+4 Tx+5 Tx+6 Tx+7 CK# CK CMD RD CKE should be kept HIGH until the end of burst operation BL=8 CKE AL+CL DQ Q Q Q Q Q Q Q Q tIS DQS DQS# Rev. 1.0 56 May /2015 EtronTech EM68A16CBQC Figure 38. Read with autoprecharge to power-down entry T0 T1 T2 Tx Tx+1 Tx+2 Tx+3 Tx+4 Tx+5 Tx+6 Tx+7 Tx+8 Tx+9 Tx+8 Tx+9 CK# CK CMD RDA PRE BL=4 CKE should be kept HIGH until the end of burst operation AL+BL/2 with tRTP = 7.5ns & tRAS min satisfied CKE AL+CL Q DQ Q Q tIS Q DQS DQS# T0 T1 T2 Tx Tx+1 Tx+2 Tx+3 Tx+4 Tx+5 Tx+6 Tx+7 CK# CK Start internal precharge CMD RD PRE BL=8 CKE should be kept HIGH until the end of burst operation AL+BL/2 with tRTP = 7.5ns & tRAS min satisfied CKE AL+CL Q DQ Q Q Q Q Q Q tIS Q DQS DQS# Figure 39. Write to power-down entry CK# T0 T1 Tm Tm+1 Tm+2 Tm+3 Tx Tx+1 Tx+2 Ty Ty+1 Ty+2 Ty+3 Tx Tx+1 Tx+2 Tx+3 Tx+4 CK CMD WR BL=4 CKE WL Q DQ Q Q tIS Q tWTR DQS DQS# CK# T0 T1 Tm Tm+1 Tm+2 Tm+3 Tm+4 Tm+5 CK CMD WR BL=8 CKE WL DQ Q Q Q Q Q Q Q tIS Q tWTR DQS DQS# Rev. 1.0 57 May /2015 EtronTech EM68A16CBQC Figure 40. Write with autoprecharge to power-down entry T0 T1 Tm Tm+1 Tm+2 Tm+3 Tx Tx+1 Tx+2 Tx+3 Tx+4 Tx+5 Tx+6 Tx+1 Tx+2 Tx+3 Tx+4 CK# CK CMD WRA PRE BL=4 CKE WL Q DQ Q Q tIS Q WR*1 DQS DQS# T0 T1 Tm Tm+1 Tm+2 Tm+3 Tm+4 Tm+5 Tx CK# CK Start internal Precharge CMD WRA PRE BL=8 CKE WL Q DQ Q Q Q Q Q Q tIS Q WR*1 DQS DQS# *1: WR is programmed through MRS Figure 41. Refresh command to power-down entry T0 T1 T2 T3 T4 T5 T6 T7 T8 T9 T10 T11 CK# CK CMD REF CKE can go to LOW one clock after an Auto-refresh command CKE tIS Rev. 1.0 58 May /2015 EtronTech EM68A16CBQC Figure 42. Active command to power-down entry T0 CMD T1 T2 T3 T4 T5 T6 T7 T8 T9 T10 T11 ACT CKE can go to LOW one clock after an Active command CKE tIS Figure 43. Precharge/precharge-all command to power-down entry T0 CMD T1 T2 T3 T4 T5 T6 T7 T8 T9 T10 T11 PR or PRA CKE can go to LOW one clock after a Precharge or Precharge all command CKE tIS Figure 44. MRS/EMRS command to power-down entry T0 CMD T1 MRS or EMRS T2 T3 T4 T5 T6 T7 T8 T9 T10 T11 tMRD CKE tIS Rev. 1.0 59 May /2015 EtronTech EM68A16CBQC Figure 45. Asynchronous CKE LOW event Stable clocks tCK CK# CK CKE tDelay CKE asynchronously drops LOW tIS Clocks can be turned off after this point Figure 46. Clock frequency change in precharge power down mode CK# CK T0 CMD T1 T2 NOP NOP T4 Tx Tx+1 Ty Ty+1 Ty+2 Ty+3 NOP NOP Ty+4 DLL RESET Tz NOP Valid Frequency Change Occurs here CKE ODT tIS tXP tRP tAOFD Minimum 2 clocks required before changing frequency Rev. 1.0 200 Clocks tIS Stable new clock before power down exit 60 tIH ODT is off during DLL RESET May /2015 EtronTech EM68A16CBQC Figure 47. 84-Ball TFBGA Package Outline Drawing Information PIN A1 INDEX Top View Bottom View Side View DETAIL : "A" Symbol A A1 D E D1 E1 F e b Rev. 1.0 Dimension in inch Min Nom Max --0.047 0.010 -0.016 0.311 0.315 0.319 0.488 0.492 0.496 -0.252 --0.441 --0.126 --0.031 -0.016 0.018 0.020 61 Dimension in mm Min Nom Max --1.20 0.25 -0.40 7.9 8.0 8.1 12.4 12.5 12.6 -6.40 --11.2 --3.2 --0.80 -0.40 0.45 0.50 May /2015