HYB25D256400/800T/AT 256-MBit Double Data Rata SDRAM Features CAS Latency and Frequency CAS Latency 2 2.5 Maximum Operating Frequency (MHz) DDR266A DDR266B DDR200 -7 -7.5 -8 133 125 100 143 133 125 . • Double data rate architecture: two data transfers per clock cycle • Bidirectional data strobe (DQS) is transmitted and received with data, to be used in capturing data at the receiver • DQS is edge-aligned with data for reads and is center-aligned with data for writes • Differential clock inputs (CK and CK) • Four internal banks for concurrent operation • Data mask (DM) for write data • DLL aligns DQ and DQS transitions with CK transitions. • Commands entered on each positive CK edge; data and data mask referenced to both edges of DQS • Burst lengths: 2, 4, or 8 • CAS Latency: 2, 2.5 • Auto Precharge option for each burst access • Auto Refresh and Self Refresh Modes • 7.8 µs Maximum Average Periodic Refresh Interval • 2.5V (SSTL_2 compatible) I/O • VDDQ = 2.5V ± 0.2V / VDD = 2.5V ± 0.2V • TSOP66 package Description The 256Mb DDR SDRAM is a high-speed CMOS, dynamic random-access memory containing 268,435,456 bits. It is internally configured as a quad-bank DRAM. The 256Mb DDR SDRAM uses a double-data-rate architecture to achieve high-speed operation. The double data rate architecture is essentially a 2n prefetch architecture with an interface designed to transfer two data words per clock cycle at the I/O pins. A single read or write access for the 256Mb DDR SDRAM effectively consists of a single 2n-bit wide, one clock cycle data transfer at the internal DRAM core and two corresponding n-bit wide, onehalf-clock-cycle data transfers at the I/O pins. A bidirectional data strobe (DQS) is transmitted externally, along with data, for use in data capture at the receiver. DQS is a strobe transmitted by the DDR SDRAM during Reads and by the memory controller during Writes. DQS is edge-aligned with data for Reads and center-aligned with data for Writes. The 256Mb DDR SDRAM operates from a differential clock (CK and CK; the crossing of CK going HIGH and CK going LOW is referred to as the positive edge of CK). Commands (address and control signals) are registered at every positive edge of CK. Input data is registered on both edges of DQS, and output data is referenced to both edges of DQS, as well as to both edges of CK. 3/01 Page 1 of 72 Read and write accesses to the DDR SDRAM are burst oriented; accesses start at a selected location and continue for a programmed number of locations in a programmed sequence. Accesses begin with the registration of an Active command, which 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. The address bits registered coincident with the Read or Write command are used to select the bank and the starting column location for the burst access. The DDR SDRAM provides for programmable Read or Write burst lengths of 2, 4 or 8 locations. An Auto Precharge function may be enabled to provide a self-timed row precharge that is initiated at the end of the burst access. As with standard SDRAMs, the pipelined, multibank architecture of DDR SDRAMs allows for concurrent operation, thereby providing high effective bandwidth by hiding row precharge and activation time. An auto refresh mode is provided along with a power-saving power-down mode. All inputs are compatible with the JEDEC Standard for SSTL_2. All outputs are SSTL_2, Class II compatible. Note: The functionality described and the timing specifications included in this data sheet are for the DLL Enabled mode of operation. HYB25D256400/800T/AT 256-Mbit Double Data Rate SDRAM Pin Configuration 66 VSS VSS 2 65 DQ7 NC 3 64 VSSQ VSSQ NC 4 63 NC NC DQ0 DQ1 5 62 DQ6 DQ3 VSSQ VSSQ 6 61 VDDQ VDDQ NC NC 7 60 NC NC NC DQ2 8 59 DQ5 NC VDDQ VDDQ 9 58 VSSQ VSSQ NC NC 10 57 NC NC DQ1 DQ3 11 56 DQ4 DQ2 VSSQ VSSQ 12 55 VDDQ VDDQ NC NC 13 54 NC NC NC NC 14 53 NC NC VDDQ VDDQ 15 52 VSSQ VSSQ NC NC 16 51 DQS DQS NC NC 17 50 NC NC VDD VDD 18 49 VREF VREF NU, QFC NU, QFC 19 48 VSS VSS NC NC 20 47 DM* DM* WE CAS WE CAS 21 46 22 45 CK CK CK CK RAS RAS 23 44 CKE CKE CS CS 24 NC NC 25 43 42 NC A12 NC A12 BA0 BA0 BA1 26 41 A11 A11 BA1 27 40 A10/AP A10/AP 28 39 A9 A8 A9 A8 A0 A0 29 38 A7 A7 A1 A1 30 37 A6 A6 A2 A2 31 36 A5 A5 A3 A3 32 35 A4 A4 VDD VDD 33 34 VSS VSS VDD VDD NC DQ0 VDDQ VDDQ NC 1 66-pin Plastic TSOP-II 400mil 32Mb x 8 64Mb x 4 I Column Address Table Organization Column Address 64Mb x 4 A0-A9, A11 32Mb x 8 A0-A9 *DM is internally loaded to match DQ and DQS identically. Page 2 of 72 3/01 HYB25D256400/800T/AT 256-Mbit Double Data Rate SDRAM Input/Output Functional Description Symbol Type Function CK, CK Input Clock: CK and CK are differential clock inputs. All address and control input signals are sampled on the crossing of the positive edge of CK and 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 HIGH activates, and CKE Low deactivates, internal clock signals and device input buffers and output drivers. Taking CKE Low provides Precharge Power-Down and Self Refresh operation (all banks idle), or Active Power-Down (row Active in any bank). CKE is synchronous for power down entry and exit, and for self refresh entry. CKE is asynchronous for self refresh exit. CKE must be maintained high throughout read and write accesses. Input buffers, excluding CK, CK and CKE are disabled during power-down. Input buffers, excluding CKE, are disabled during self refresh. CS Input Chip Select: All commands are masked when CS is registered HIGH. CS provides for external bank selection on systems with multiple banks. CS is considered part of the command code. The standard pinout includes one CS pin. RAS, CAS, WE Input Command Inputs: RAS, CAS and WE (along with CS) define the command being entered. DM Input Input Data Mask: DM is an input mask signal for write data. Input data is masked when DM is sampled HIGH coincident with that input data during a Write access. DM is sampled on both edges of DQS. Although DM pins are input only, the DM loading matches the DQ and DQS loading. BA0, BA1 Input Bank Address Inputs: BA0 and BA1 define to which bank an Active, Read, Write or Precharge command is being applied. BA0 and BA1 also determines if the mode register or extended mode register is to be accessed during a MRS or EMRS cycle. A0 - A12 Input Address Inputs: Provide the row address for Active commands, and the column address and Auto Precharge bit for Read/Write commands, to select one location out of the memory array in the respective bank. A10 is sampled during a Precharge command to determine whether the Precharge applies to one bank (A10 LOW) or all banks (A10 HIGH). If only one bank is to be precharged, the bank is selected by BA0, BA1. The address inputs also provide the op-code during a Mode Register Set command. DQ Input/Output Data Input/Output: Data bus. DQS Input/Output Data Strobe: Output with read data, input with write data. Edge-aligned with read data, centered in write data. Used to capture write data. Output FET control: Optional. Output during every Read and Write access. Is provided to control isolation switches on modules. Open drain output. Pullup resistor must be tied to VDDQ at second level of assembly. The QFC pin is present on this product version, but all timings parameters related to this pin are not tested on the final product and are only guaranteed by design. VDDQ Supply DQ Power Supply: 2.5V ± 0.2V. VSSQ Supply DQ Ground VDD Supply Power Supply: 2.5V ± 0.2V. VSS Supply Ground VREF Supply SSTL_2 reference voltage: (V DDQ / 2) QFC NC Page 3 of 72 No Connect: No internal electrical connection is present. 3/01 HYB25D256400/800T/AT 256-Mbit Double Data Rate SDRAM Ordering Information Part Number (ASTC) CAS Latency HYB25D256400T-7 HYB25D256800T-7.5 2.5 HYB25D256400T-8 CAS Latency HYB25D256400AT-7 HYB25D256800AT-7.5 HYB25D256400AT-8 HYB25D256800AT-8 Page 4 of 72 2 Clock (MHz) CAS Latency 143 HYB25D256800AT-7 HYB25D256400AT-7.5 133 125 HYB25D256800T-8 Part Number (WOS) CAS Latency 143 HYB25D256800T-7 HYB25D256400T-7.5 Clock (MHz) 2.5 133 125 2 Clock (MHz) Speed 133 DDR266A 125 DDR266B 100 DDR200 Clock (MHz) Speed 133 DDR266A 125 DDR266B 100 DDR200 Org. Package x4 x8 x4 x8 66 pin TSOP-II x4 x8 Org. Package x4 x8 x4 x8 66 pin TSOP-II x4 x8 3/01 HYB25D256400/800T/AT 256-Mbit Double Data Rate SDRAM Block Diagram (64Mb x 4) Control Logic QFC generator 2 Bank2 Bank3 CK, CK DLL 8 8192 4 4 1 DQS Generator COL0 I/O Gating DM Mask Logic 1024 (x8) Column Decoder 8 8 Write FIFO & Drivers Column-Address Counter/Latch COL0 1 Input Register 1 Mask 1 1 1 4 4 4 clk clk out in Data 4 2 8 10 11 Drivers Data 4 MUX Bank0 Memory Array (8192 x 1024 x 8) Read Latch 8192 Sense Amplifiers 2 QFC (Optional) DRVR CK, CK DQS DQ0-DQ3, DM DQS 1 Receivers 15 Refresh Counter 13 A0-A12, BA0, BA1 13 Address Register 15 13 Bank Control Logic Mode Registers Bank0 Row-Address Latch & Decoder Bank1 Row-Address MUX Command Decode CKE CK CK CS WE CAS RAS 4 COL0 1 Note: This Functional Block Diagram is intended to facilitate user understanding of the operation of the device; it does not represent an actual circuit implementation. Note: DM is a unidirectional signal (input only), but is internally loaded to match the load of the bidirectional DQ and DQS signals. Page 5 of 72 3/01 HYB25D256400/800T/AT 256-Mbit Double Data Rate SDRAM Block Diagram (32Mb x 8) Control Logic QFC generator DLL 16 Data 8 8 512 (x16) Column Decoder 16 16 Write FIFO & Drivers 1 Column-Address Counter/Latch COL0 1 Input Register 1 Mask 1 1 1 8 8 8 clk clk out in Data 8 2 16 9 10 8 DQS Generator COL0 I/O Gating DM Mask Logic Drivers Bank0 Memory Array (8192 x 512 x 16) MUX 8192 CK, CK DQS DQ0-DQ7, DM DQS 1 Receivers 2 CK, CK Sense Amplifiers 2 QFC (Optional) DRVR Bank3 Read Latch Refresh Counter 13 15 Address Register A0-A12, BA0, BA1 Bank2 8192 13 15 13 Bank Control Logic Mode Registers Bank0 Row-Address Latch & Decoder Bank1 Row-Address MUX Command Decode CKE CK CK CS WE CAS RAS 8 COL0 1 Note: This Functional Block Diagram is intended to facilitate user understanding of the operation of the device; it does not represent an actual circuit implementation. Note: DM is a unidirectional signal (input only), but is internally loaded to match the load of the bidirectional DQ and DQS signals. Page 6 of 72 3/01 HYB25D256400/800T/AT 256-Mbit Double Data Rate SDRAM Functional Description The 256Mb DDR SDRAM is a high-speed CMOS, dynamic random-access memory containing 268, 435, 456 bits. The 256Mb DDR SDRAM is internally configured as a quad-bank DRAM. The 256Mb DDR SDRAM uses a double-data-rate architecture to achieve high-speed operation. The doubledata-rate architecture is essentially a 2n prefetch architecture, with an interface designed to transfer two data words per clock cycle at the I/O pins. A single read or write access for the 256Mb DDR SDRAM consists of a single 2n-bit wide, one clock cycle data transfer at the internal DRAM core and two corresponding n-bit wide, one-half clock cycle data transfers at the I/O pins. Read and write accesses to the DDR SDRAM are burst oriented; accesses start at a selected location and continue for a programmed number of locations in a programmed sequence. Accesses begin with the registration of an Active command, which 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. Prior to normal operation, the DDR SDRAM must be initialized. The following sections provide detailed information covering device initialization, register definition, command descriptions and device operation. Initialization DDR SDRAMs must be powered up and initialized in a predefined manner. Operational procedures other than those specified may result in undefined operation. The following two conditions must be met: No power sequening is specified during power up or power down given the follwing criteria VDD and VDDQ are driven from a single power converter output VTT meets the specification A minimum resistance of 42 ohms limits the input current from the VTT supply into any pin and VREF tracks VDDQ/2 or The following relationship must be followed VDDQ is driven after or with VDD such that VDDQ < VDD + 0.3 V VTT is driven after or with VDDQ such that VTT < VDDQ + 0.3V VREF is driven after or with VDDQ such that VREF < VDDQ + 0.3V The DQ and DQS outputs are in the High-Z state, where they remain until driven in normal operation (by a read access). After all power supply and reference voltages are stable, and the clock is stable, the DDR SDRAM requires a 200µs delay prior to applying an executable command. Once the 200µs delay has been satisfied, a Deselect or NOP command should be applied, and CKE must be brought HIGH. Following the NOP command, a Precharge ALL command must be applied. Next a Mode Register Set command must be issued for the Extended Mode Register, to enable the DLL, then a Mode Register Set command must be issued for the Mode Register, to reset the DLL, and to program the operating parameters. 200 clock cycles are required between the DLL reset and any read command. A Precharge ALL command should be applied, placing the device in the “all banks idle” state Once in the idle state, two AUTO REFRESH cycles must be performed. Additionally, a Mode Register Set command for the Mode Register, with the reset DLL bit deactivated (i.e. to program operating parameters without resetting the DLL) must be performed. Following these cycles, the DDR SDRAM is ready for normal operation. Page 7 of 72 3/01 HYB25D256400/800T/AT 256-Mbit Double Data Rate SDRAM Register Definition Mode Register The Mode Register is used to define the specific mode of operation of the DDR SDRAM. This definition includes the selection of a burst length, a burst type, a CAS latency, and an operating mode. The Mode Register is programmed via the Mode Register Set command (with BA0 = 0 and BA1 = 0) and retains the stored information until it is programmed again or the device loses power (except for bit A8, which is self-clearing). Mode Register bits A0-A2 specify the burst length, A3 specifies the type of burst (sequential or interleaved), A4-A6 specify the CAS latency, and A7-A12 specify the operating mode. The Mode Register must be loaded when all banks are idle, and the controller must wait the specified time before initiating the subsequent operation. Violating either of these requirements results in unspecified operation. Burst Length Read and write accesses to the DDR SDRAM are burst oriented, with the burst length being programmable. The burst length determines the maximum number of column locations that can be accessed for a given Read or Write command. Burst lengths of 2, 4, or 8 locations are available for both the sequential and the interleaved burst types. Reserved states should not be used, as unknown operation or incompatibility with future versions may result. When a Read or Write command is issued, a block of columns equal to the burst length is effectively selected. All accesses for that burst take place within this block, meaning that the burst wraps within the block if a boundary is reached. The block is uniquely selected by A1-Ai when the burst length is set to two, by A2-Ai when the burst length is set to four and by A3-Ai when the burst length is set to eight (where Ai is the most significant column address bit for a given configuration). The remaining (least significant) address bit(s) is (are) used to select the starting location within the block. The programmed burst length applies to both Read and Write bursts. Page 8 of 72 3/01 HYB25D256400/800T/AT 256-Mbit Double Data Rate SDRAM Mode Register Operation BA1 BA0 0* 0* A12 - A9 0 0 A8 0 1 A12 A11 A10 A9 A8 A7 0 0 A5 A4 CAS Latency Operating Mode A7 A6 A3 BT A2 Burst Length A6 - A0 Operating Mode Valid Normal operation Do not reset DLL A3 Burst Type 0 Sequential Normal operation in DLL Reset 1 Interleave Valid 0 0 1 Reserved − − − Reserved CAS Latency A1 A0 Address Bus Mode Register Burst Length A6 A5 A4 Latency A2 A1 A0 Burst Length 0 0 0 Reserved 0 0 0 Reserved 0 0 1 Reserved 0 0 1 2 0 1 0 2 0 1 0 4 0 1 1 Reserved 0 1 1 8 1 0 0 Reserved 1 0 0 Reserved 1 0 1 Reserved 1 0 1 Reserved 1 1 0 2.5 1 1 0 Reserved 1 1 1 Reserved 1 1 1 Reserved VS** Vendor Specific * BA0 and BA1 must be 0, 0 to select the Mode Register (vs. the Extended Mode Register). Page 9 of 72 3/01 HYB25D256400/800T/AT 256-Mbit Double Data Rate SDRAM Burst Definition Starting Column Address Order of Accesses Within a Burst Burst Length A2 A1 A0 Type = Sequential Type = Interleaved 0 0-1 0-1 1 1-0 1-0 0 0 0-1-2-3 0-1-2-3 0 1 1-2-3-0 1-0-3-2 1 0 2-3-0-1 2-3-0-1 1 1 3-0-1-2 3-2-1-0 0 0 0 0-1-2-3-4-5-6-7 0-1-2-3-4-5-6-7 0 0 1 1-2-3-4-5-6-7-0 1-0-3-2-5-4-7-6 0 1 0 2-3-4-5-6-7-0-1 2-3-0-1-6-7-4-5 0 1 1 3-4-5-6-7-0-1-2 3-2-1-0-7-6-5-4 1 0 0 4-5-6-7-0-1-2-3 4-5-6-7-0-1-2-3 1 0 1 5-6-7-0-1-2-3-4 5-4-7-6-1-0-3-2 1 1 0 6-7-0-1-2-3-4-5 6-7-4-5-2-3-0-1 1 1 1 7-0-1-2-3-4-5-6 7-6-5-4-3-2-1-0 2 4 8 Notes: 1. For a burst length of two, A1-Ai selects the two-data-element block; A0 selects the first access within the block. 2. For a burst length of four, A2-Ai selects the four-data-element block; A0-A1 selects the first access within the block. 3. For a burst length of eight, A3-Ai selects the eight-data- element block; A0-A2 selects the first access within the block. 4. Whenever a boundary of the block is reached within a given sequence above, the following access wraps within the block. Burst Type Accesses within a given burst may be programmed to be either sequential or interleaved; this is referred to as the burst type and is selected via bit A3. The ordering of accesses within a burst is determined by the burst length, the burst type and the starting column address, as shown in Burst Definition on page 10. Read Latency The Read latency, or CAS latency, is the delay, in clock cycles, between the registration of a Read command and the availability of the first burst of output data. The latency can be programmed 2 or 2.5 clocks. If a Read command is registered at clock edge n, and the latency is m clocks, the data is available nominally coincident with clock edge n + m. Reserved states should not be used as unknown operation or incompatibility with future versions may result. Page 10 of 72 3/01 HYB25D256400/800T/AT 256-Mbit Double Data Rate SDRAM Operating Mode The normal operating mode is selected by issuing a Mode Register Set Command with bits A7-A12 to zero, and bits A0-A6 set to the desired values. A DLL reset is initiated by issuing a Mode Register Set command with bits A7 and A9-A12 each set to zero, bit A8 set to one, and bits A0-A6 set to the desired values. A Mode Register Set command issued to reset the DLL should always be followed by a Mode Register Set command to select normal operating mode. All other combinations of values for A7-A12 are reserved for future use and/or test modes. Test modes and reserved states should not be used as unknown operation or incompatibility with future versions may result. Required CAS Latencies CAS Latency = 2, BL = 4 CK CK Command Read NOP NOP NOP NOP NOP CL=2 DQS DQ CAS Latency = 2.5, BL = 4 CK CK Command Read NOP NOP NOP NOP NOP CL=2.5 DQS DQ Shown with nominal tAC , tDQSCK, and tDQSQ. Page 11 of 72 Don’t Care 3/01 HYB25D256400/800T/AT 256-Mbit Double Data Rate SDRAM Extended Mode Register The Extended Mode Register controls functions beyond those controlled by the Mode Register; these additional functions include DLL enable/disable, output drive strength selection (optional), and QFC output enable/disable (optional). These functions are controlled via the bits shown in the Extended Mode Register Definition. The Extended Mode Register is programmed via the Mode Register Set command (with BA0 = 1 and BA1 = 0) and retains the stored information until it is programmed again or the device loses power. The Extended Mode Register must be loaded when all banks are idle, and the controller must wait the specified time before initiating any subsequent operation. Violating either of these requirements result in unspecified operation. 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 disabled the DLL for the purpose of debug or evaluation. 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, 200 clock cycles must occur before a Read command can be issued. This is the reason 200 clock cycles must occur before issuing a Read or Write command upon exit of self refresh operation. Output Drive Strength The normal drive strength for all outputs is specified to be SSTL_2, Class II. I-V curves for the normal drive strength are included in this document. An option for weak driver support intended for lighter load and/or point-to-point environments is under consideration for future versions of this design. Selection of the weak driver option will reduce the output drive strength by ~ 55% of that of the normal strength. QFC Enable/Disable (optional) The QFC signal is an optional DRAM output control used to isolate module loads (DIMMs) from the system memory bus by means of FET switches when the given module is not being accessed. The QFC pin is present on this product version, but all timings parameters related to this pin are not tested on the final product and are only guaranteed by design. Page 12 of 72 3/01 HYB25D256400/800T/AT 256-Mbit Double Data Rate SDRAM Extended Mode Register Definition BA1 BA0 0* 1* A12 A11 A 10 A8 A9 A7 A6 A5 A4 A3 Operating Mode A2 A1 A0 Address Bus QFC DS DLL Extended Mode Register Drive Strength An - A3 A2 - A0 Operating Mode 0 Valid Normal Operation − − All other states Reserved A2 QFC 0 Disable 1 Enable (Optional) * BA0 and BA1 must be 1, 0 to select the Extended Mode Register (vs. the base Mode Register) Page 13 of 72 A1 Drive Strength 0 Normal 1 reserved A0 DLL 0 Enable 1 Disable 3/01 HYB25D256400/800T/AT 256-Mbit Double Data Rate SDRAM Truth Table 1a: Commands Name (Function) CS RAS CAS WE Address MNE Notes Deselect (Nop) H X X X X NOP 1, 9 No Operation (Nop) L H H H X NOP 1, 9 Active (Select Bank And Activate Row) L L H H Bank/Row ACT 1, 3 Read (Select Bank And Column, And Start Read Burst) L H L H Bank/Col Read 1, 4 Write (Select Bank And Column, And Start Write Burst) L H L L Bank/Col Write 1, 4 Burst Terminate L H H L X BST 1, 8 Precharge (Deactivate Row In Bank Or Banks) L L H L Code PRE 1, 5 Auto Refresh Or Self Refresh (Enter Self Refresh Mode) L L L H X AR / SR 1, 6, 7 Mode Register Set L L L L Op-Code MRS 1, 2 1. CKE is HIGH for all commands shown except Self Refresh. 2. BA0, BA1 select either the Base or the Extended Mode Register (BA0 = 0, BA1 = 0 selects Mode Register; BA0 = 1, BA1 = 0 selects Extended Mode Register; other combinations of BA0-BA1 are reserved; A0-A12 provide the op-code to be written to the selected Mode Register.) 3. BA0-BA1 provide bank address and A0-A12 provide row address. 4. BA0, BA1 provide bank address; A0-Ai provide column address (where i = 9 for x8 and 9, 11 for x4); A10 HIGH enables the Auto Precharge feature (nonpersistent), A10 LOW disables the Auto Precharge feature. 5. A10 LOW: BA0, BA1 determine which bank is precharged. A10 HIGH: all banks are precharged and BA0, BA1 are “Don’t Care.” 6. This command is AUTO REFRESH if CKE is HIGH; Self Refresh if CKE is LOW. 7. Internal refresh counter controls row and bank addressing; all inputs and I/Os are “Don’t Care” except for CKE. 8. Applies only to read bursts with Auto Precharge disabled; this command is undefined (and should not be used) for read bursts with Auto Precharge enabled or for write bursts 9. Deselect and NOP are functionally interchangeable. Truth Table 1b: DM Operation Name (Function) DM DQs Notes Write Enable L Valid 1 Write Inhibit H X 1 1. Used to mask write data; provided coincident with the corresponding data. Page 14 of 72 3/01 HYB25D256400/800T/AT 256-Mbit Double Data Rate SDRAM Deselect The Deselect function prevents new commands from being executed by the DDR SDRAM. The DDR SDRAM is effectively deselected. Operations already in progress are not affected. No Operation (NOP) The No Operation (NOP) command is used to perform a NOP to a DDR SDRAM. This prevents unwanted commands from being registered during idle or wait states. Operations already in progress are not affected. Mode Register Set The mode registers are loaded via inputs A0-A12, BA0 and BA1. See mode register descriptions in the Register Definition section. The Mode Register Set command can only be issued when all banks are idle and no bursts are in progress. A subsequent executable command cannot be issued until tMRD is met. Active The Active command is used to open (or activate) a row in a particular bank for a subsequent access. The value on the BA0, BA1 inputs selects the bank, and the address provided on inputs A0-A12 selects the row. This row remains active (or open) for accesses until a Precharge (or Read or Write with Auto Precharge) is issued to that bank. A Precharge (or Read or Write with Auto Precharge) command must be issued and completed before opening a different row in the same bank. Read The Read command is used to initiate a burst read access to an active (open) row. The value on the BA0, BA1 inputs selects the bank, and the address provided on inputs A0-Ai, Aj (where [i = 9, j = don’t care] for x8; where [i = 9, j = 11] for x4) selects the starting column location. The value on input A10 determines whether or not Auto Precharge is used. If Auto Precharge is selected, the row being accessed is precharged at the end of the Read burst; if Auto Precharge is not selected, the row remains open for subsequent accesses. Write The Write command is used to initiate a burst write access to an active (open) row. The value on the BA0, BA1 inputs selects the bank, and the address provided on inputs A0-Ai, Aj (where [i = 9, j = don’t care] for x8; where [i = 9, j = 11] for x4) selects the starting column location. The value on input A10 determines whether or not Auto Precharge is used. If Auto Precharge is selected, the row being accessed is precharged at the end of the Write burst; if Auto Precharge is not selected, the row remains open for subsequent accesses. Input data appearing on the DQs is written to the memory array subject to the DM input logic level appearing coincident with the data. If a given DM signal is registered low, the corresponding data is written to memory; if the DM signal is registered high, the corresponding data inputs are ignored, and a Write is not executed to that byte/column location. Precharge The Precharge command is used to deactivate (close) the open row in a particular bank or the open row(s) in all banks. The bank(s) will be available for a subsequent row access a specified time (tRP) after the Precharge command is issued. Input A10 determines whether one or all banks are to be precharged, and in the case where only one bank is to be precharged, inputs BA0, BA1 select the bank. Otherwise BA0, BA1 are treated as “Don’t Care.” Once a bank has been precharged, it is in the idle state and must be activated prior to any Read or Write commands being issued to that bank. A precharge command is treated as a NOP if there is no open row in that bank, or if the previously open row is already in the process of precharging. Page 15 of 72 3/01 HYB25D256400/800T/AT 256-Mbit Double Data Rate SDRAM Auto Precharge Auto Precharge is a feature which performs the same individual-bank precharge function described above, but without requiring an explicit command. This is accomplished by using A10 to enable Auto Precharge in conjunction with a specific Read or Write command. A precharge of the bank/row that is addressed with the Read or Write command is automatically performed upon completion of the Read or Write burst. Auto Precharge is nonpersistent in that it is either enabled or disabled for each individual Read or Write command. Auto Precharge ensures that the precharge is initiated at the earliest valid stage within a burst. The user must not issue another command to the same bank until the precharge (tRP) is completed. This is determined as if an explicit Precharge command was issued at the earliest possible time, as described for each burst type in the Operation section of this data sheet. Burst Terminate The Burst Terminate command is used to truncate read bursts (with Auto Precharge disabled). The most recently registered Read command prior to the Burst Terminate command is truncated, as shown in the Operation section of this data sheet. Auto Refresh Auto Refresh is used during normal operation of the DDR SDRAM and is analogous to CAS Before RAS (CBR) Refresh in previous DRAM types. This command is nonpersistent, so it must be issued each time a refresh is required. The refresh addressing is generated by the internal refresh controller. This makes the address bits “Don’t Care” during an Auto Refresh command. The 256Mb DDR SDRAM requires Auto Refresh cycles at an average periodic interval of 7.8µs (maximum). To allow for improved efficiency in scheduling and switching between tasks, some flexibility in the absolute refresh interval is provided. A maximum of eight Auto Refresh commands can be posted in the system, meaning that the maximum absolute interval between any Auto Refresh command and the next Auto Refresh command is 9 * 7.8 µs (70.2µs). This maximum absolute interval is short enough to allow for DLL updates internal to the DDR SDRAM to be restricted to Auto Refresh cycles, without allowing too much drift in tAC between updates. Self Refresh The Self Refresh command can be used to retain data in the DDR SDRAM, even if the rest of the system is powered down. When in the self refresh mode, the DDR SDRAM retains data without external clocking. The Self Refresh command is initiated as an Auto Refresh command coincident with CKE transitioning low. The DLL is automatically disabled upon entering Self Refresh, and is automatically enabled upon exiting Self Refresh (200 clock cycles must then occur before a Read command can be issued). Input signals except CKE (low) are “Don’t Care” during Self Refresh operation. The procedure for exiting self refresh requires a sequence of commands. CK (and CK) must be stable prior to CKE returning high. Once CKE is high, the SDRAM must have NOP commands issued for tXSNR because time is required for the completion of any internal refresh in progress. A simple algorithm for meeting both refresh and DLL requirements is to apply NOPs for 200 clock cycles before applying any other command. Page 16 of 72 3/01 HYB25D256400/800T/AT 256-Mbit Double Data Rate SDRAM Operations Bank/Row Activation Before any Read or Write commands can be issued to a bank within the DDR SDRAM, a row in that bank must be “opened” (activated). This is accomplished via the Active command and addresses A0-A12, BA0 and BA1 (see Activating a Specific Row in a Specific Bank), which decode and select both the bank and the row to be activated. After opening a row (issuing an Active command), a Read or Write command may be issued to that row, subject to the tRCD specification. A subsequent Active command to a different row in the same bank can only be issued after the previous active row has been “closed” (precharged). The minimum time interval between successive Active commands to the same bank is defined by tRC. A subsequent Active command to another bank can be issued while the first bank is being accessed, which results in a reduction of total row-access overhead. The minimum time interval between successive Active commands to different banks is defined by tRRD. Activating a Specific Row in a Specific Bank CK CK CKE HIGH CS RAS CAS WE Page 17 of 72 A0-A12 RA BA0, BA1 BA RA = row address. BA = bank address. Don’t Care 3/01 HYB25D256400/800T/AT 256-Mbit Double Data Rate SDRAM tRCD and tRRD Definition CK CK NOP ACT A0-A12 ROW ROW COL BA0, BA1 BA x BA y BA y tRRD ACT NOP NOP RD/WR Command NOP NOP tRCD Don’t Care Reads Subsequent to programming the mode register with CAS latency, burst type, and burst length, Read bursts are initiated with a Read command, as shown on Read Command on page 19. The starting column and bank addresses are provided with the Read command and Auto Precharge is either enabled or disabled for that burst access. If Auto Precharge is enabled, the row that is accessed starts precharge at the completion of the burst, provided tRAS has been satisfied. For the generic Read commands used in the following illustrations, Auto Precharge is disabled. During Read bursts, the valid data-out element from the starting column address is available following the CAS latency after the Read command. Each subsequent data-out element is valid nominally at the next positive or negative clock edge (i.e. at the next crossing of CK and CK). Read Burst: CAS Latencies (Burst Length = 4) on page 20 shows general timing for each supported CAS latency setting. DQS is driven by the DDR SDRAM along with output data. The initial low state on DQS is known as the read preamble; the low state coincident with the last data-out element is known as the read postamble. Upon completion of a burst, assuming no other commands have been initiated, the DQs goes High-Z. Data from any Read burst may be concatenated with or truncated with data from a subsequent Read command. In either case, a continuous flow of data can be maintained. The first data element from the new burst follows either the last element of a completed burst or the last desired data element of a longer burst which is being truncated. The new Read command should be issued x cycles after the first Read command, where x equals the number of desired data element pairs (pairs are required by the 2n prefetch architecture). This is shown on Consecutive Read Bursts: CAS Latencies (Burst Length = 4 or 8) on page 21. A Read command can be initiated on any clock cycle following a previous Read command. Nonconsecutive Read data is illustrated on Non-Consecutive Read Bursts: CAS Latencies (Burst Length = 4) on page 22. Full-speed Random Read Accesses: CAS Latencies (Burst Length = 2, 4 or 8) within a page (or pages) can be performed as shown on page 23. Page 18 of 72 3/01 HYB25D256400/800T/AT 256-Mbit Double Data Rate SDRAM Read Command CK CK CKE HIGH CS RAS CAS WE x4: A0-A9, A11 x8: A0-A9 CA EN AP A10 DIS AP BA0, BA1 BA CA = column address BA = bank address EN AP = enable Auto Precharge DIS AP = disable Auto Precharge Don’t Care Page 19 of 72 3/01 HYB25D256400/800T/AT 256-Mbit Double Data Rate SDRAM Read Burst: CAS Latencies (Burst Length = 4) CAS Latency = 2 CK CK Command Address Read NOP NOP NOP NOP NOP BA a,COL n CL=2 DQS DOa-n DQ tQPRE tQPST QFC (Optional) CAS Latency = 2.5 CK CK Command Address Read NOP NOP NOP NOP NOP BA a,COL n CL=2.5 DQS DOa-n DQ QFC (Optional) tQPRE tQPST Don’t Care DO a-n = data out from bank a, column n. 3 subsequent elements of data out appear in the programmed order following DO a-n. Shown with nominal tAC, tDQSCK, and tDQSQ. QFC is an open drain driver. The output high level is achieved through an external pull up resistor connected to VDDQ. Page 20 of 72 3/01 HYB25D256400/800T/AT 256-Mbit Double Data Rate SDRAM Consecutive Read Bursts: CAS Latencies (Burst Length = 4 or 8) CAS Latency = 2 CK CK Command Address Read NOP Read BAa, COL n NOP NOP NOP BAa, COL b CL=2 DQS DQ DOa-n DOa-b CAS Latency = 2.5 CK CK Command Address Read NOP Read BAa, COL n NOP NOP NOP BAa,COL b CL=2.5 DQS DQ DOa- n DO a-n (or a-b) = data out from bank a, column n (or bank a, column b). When burst length = 4, the bursts are concatenated. When burst length = 8, the second burst interrupts the first. 3 subsequent elements of data out appear in the programmed order following DO a-n. 3 (or 7) subsequent elements of data out appear in the programmed order following DO a-b. Shown with nominal tAC , tDQSCK, and tDQSQ. Page 21 of 72 DOa- b Don’t Care 3/01 HYB25D256400/800T/AT 256-Mbit Double Data Rate SDRAM Non-Consecutive Read Bursts: CAS Latencies (Burst Length = 4) CAS Latency = 2 CK CK Read Command Address NOP NOP Read BAa, COL n NOP NOP BAa, COL b CL=2 DQS DO a-n DQ DOa- b CAS Latency = 2.5 CK CK Command Address Read NOP BAa, COL n NOP Read NOP NOP NOP BAa, COL b CL=2.5 DQS DQ DO a-n DO a-n (or a-b) = data out from bank a, column n (or bank a, column b). 3 subsequent elements of data out appear in the programmed order following DO a-n (and following DO a-b). Shown with nominal tAC, tDQSCK, and tDQSQ. Page 22 of 72 DOa- b Don’t Care 3/01 HYB25D256400/800T/AT 256-Mbit Double Data Rate SDRAM Random Read Accesses: CAS Latencies (Burst Length = 2, 4 or 8) CAS Latency = 2 CK CK Command Address Read Read Read Read NOP BAa, COL n BAa, COL x BAa, COL b BAa, COL g NOP CL=2 DQS DQ DOa-n DOa-n’ DOa-x DOa-x’ DOa-b DOa-b’ DOa-g CAS Latency = 2.5 CK CK Command Address Read Read Read Read BAa, COL n BAa, COL x BAa, COL b BAa, COL g NOP NOP CL=2.5 DQS DQ DOa-n DO a-n, etc. = data out from bank a, column n etc. n’ etc. = odd or even complement of n, etc. (i.e., column address LSB inverted). Reads are to active rows in any banks. Shown with nominal tAC , tDQSCK, and tDQSQ . Page 23 of 72 DOa-n’ DOa-x DOa-x’ DOa-b DOa-b’ Don’t Care 3/01 HYB25D256400/800T/AT 256-Mbit Double Data Rate SDRAM Data from any Read burst may be truncated with a Burst Terminate command, as shown on Terminating a Read Burst: CAS Latencies (Burst Length = 8) on page 25. The Burst Terminate latency is equal to the read (CAS) latency, i.e. the Burst Terminate command should be issued x cycles after the Read command, where x equals the number of desired data element pairs. Data from any Read burst must be completed or truncated before a subsequent Write command can be issued. If truncation is necessary, the Burst Terminate command must be used, as shown on Read to Write: CAS Latencies (Burst Length = 4 or 8) on page 26. The example is shown for tDQSS(min). The tDQSS(max) case, not shown here, has a longer bus idle time. tDQSS(min) and tDQSS(max) are defined in the section on Writes. A Read burst may be followed by, or truncated with, a Precharge command to the same bank (provided that Auto Precharge was not activated). The Precharge command should be issued x cycles after the Read command, where x equals the number of desired data element pairs (pairs are required by the 2n prefetch architecture). This is shown on Read to Precharge: CAS Latencies (Burst Length = 4 or 8) on page 27 for Read latencies of 2 and 2.5. Following the Precharge command, a subsequent command to the same bank cannot be issued until tRP is met. Note that part of the row precharge time is hidden during the access of the last data elements. In the case of a Read being executed to completion, a Precharge command issued at the optimum time (as described above) provides the same operation that would result from the same Read burst with Auto Precharge enabled. The disadvantage of the Precharge command is that it requires that the command and address busses be available at the appropriate time to issue the command. The advantage of the Precharge command is that it can be used to truncate bursts. Page 24 of 72 3/01 HYB25D256400/800T/AT 256-Mbit Double Data Rate SDRAM Terminating a Read Burst: CAS Latencies (Burst Length = 8) CAS Latency = 2 CK CK Command Address Read NOP BST NOP NOP NOP BAa, COL n CL=2 DQS DQ DOa-n No further output data after this point. DQS tristated. CAS Latency = 2.5 CK CK Command Address Read NOP BST NOP NOP NOP BAa, COL n CL=2.5 DQS DQ DOa-n No further output data after this point. DQS tristated. DO a-n = data out from bank a, column n. Cases shown are bursts of 8 terminated after 4 data elements. 3 subsequent elements of data out appear in the programmed order following DO a-n. Shown with nominal tAC, tDQSCK, and tDQSQ. Page 25 of 72 Don’t Care 3/01 HYB25D256400/800T/AT 256-Mbit Double Data Rate SDRAM Read to Write: CAS Latencies (Burst Length = 4 or 8) CAS Latency = 2 CK CK Command Address Read BST NOP BAa, COL n Write NOP NOP BAa, COL b CL=2 tDQSS (min) DQS DQ DI a-b DOa-n DM CAS Latency = 2.5 CK CK Command Address Read BST NOP NOP BAa, COL n Write NOP BAa, COL b CL=2.5 tDQSS (min) DQS DQ DOa-n Dla-b DM DO a-n = data out from bank a, column n .DI a-b = data in to bank a, column b 1 subsequent elements of data out appear in the programmed order following DO a-n. Data In elements are applied following Dl a-b in the programmed order, according to burst length. Shown with nominal tAC, tDQSCK, and tDQSQ. Page 26 of 72 Don’t Care 3/01 HYB25D256400/800T/AT 256-Mbit Double Data Rate SDRAM Read to Precharge: CAS Latencies (Burst Length = 4 or 8) CAS Latency = 2 CK CK Command Read NOP PRE NOP NOP ACT tRP Address BA a or all BA a, COL n BA a, ROW CL=2 DQS DQ DOa-n CAS Latency = 2.5 CK CK Command Read NOP PRE NOP NOP ACT tRP Address BA a or all BA a, COL n BA a, ROW CL=2.5 DQS DQ DOa-n DO a-n = data out from bank a, column n. Cases shown are either uninterrupted bursts of 4 or interrupted bursts of 8. 3 subsequent elements of data out appear in the programmed order following DO a-n. Shown with nominal tAC , tDQSCK, and tDQSQ. Page 27 of 72 Don’t Care 3/01 HYB25D256400/800T/AT 256-Mbit Double Data Rate SDRAM Writes Write bursts are initiated with a Write command, as shown on Write Command on page 29. The starting column and bank addresses are provided with the Write command, and Auto Precharge is either enabled or disabled for that access. If Auto Precharge is enabled, the row being accessed is precharged at the completion of the burst. For the generic Write commands used in the following illustrations, Auto Precharge is disabled. During Write bursts, the first valid data-in element is registered on the first rising edge of DQS following the write command, and subsequent data elements are registered on successive edges of DQS. The Low state on DQS between the Write command and the first rising edge is known as the write preamble; the Low state on DQS following the last data-in element is known as the write postamble. The time between the Write command and the first corresponding rising edge of DQS (tDQSS) is specified with a relatively wide range (from 75% to 125% of one clock cycle), so most of the Write diagrams that follow are drawn for the two extreme cases (i.e. tDQSS(min) and tDQSS(max)). Write Burst (Burst Length = 4) on page 30 shows the two extremes of tDQSS for a burst of four. Upon completion of a burst, assuming no other commands have been initiated, the DQs and DQS enters High-Z and any additional input data is ignored. Data for any Write burst may be concatenated with or truncated with a subsequent Write command. In either case, a continuous flow of input data can be maintained. The new Write command can be issued on any positive edge of clock following the previous Write command. The first data element from the new burst is applied after either the last element of a completed burst or the last desired data element of a longer burst which is being truncated. The new Write command should be issued x cycles after the first Write command, where x equals the number of desired data element pairs (pairs are required by the 2n prefetch architecture). Write to Write (Burst Length = 4) on page 31 shows concatenated bursts of 4. An example of non-consecutive Writes is shown on Write to Write: Max DQSS, Non-Consecutive (Burst Length = 4) on page 32. Full-speed random write accesses within a page or pages can be performed as shown on Random Write Cycles (Burst Length = 2, 4 or 8) on page 33. Data for any Write burst may be followed by a subsequent Read command. To follow a Write without truncating the write burst, tWTR (Write to Read) should be met as shown on Write to Read: NonInterrupting (CAS Latency = 2; Burst Length = 4) on page 34. Data for any Write burst may be truncated by a subsequent Read command, as shown in the figures on Write to Read: Interrupting (CAS Latency = 2; Burst Length = 8) on page 35 to Write to Read: Nominal DQSS, Interrupting (CAS Latency = 2; Burst Length = 8) on page 37. Note that only the data-in pairs that are registered prior to the tWTR period are written to the internal array, and any subsequent data-in must be masked with DM, as shown in the diagrams noted previously. Data for any Write burst may be followed by a subsequent Precharge command. To follow a Write without truncating the write burst, tWR should be met as shown on Write to Precharge: Non-Interrupting (Burst Length = 4) on page 38. Data for any Write burst may be truncated by a subsequent Precharge command, as shown in the figures on Write to Precharge: Interrupting (Burst Length = 4 or 8) on page 39 to Write to Precharge: Nominal DQSS (2 bit Write), Interrupting (Burst Length = 4 or 8) on page 41. Note that only the data-in pairs that are registered prior to the tWR period are written to the internal array, and any subsequent data in should be masked with DM. Following the Precharge command, a subsequent command to the same bank cannot be issued until tRP is met. In the case of a Write burst being executed to completion, a Precharge command issued at the optimum time (as described above) provides the same operation that would result from the same burst with Auto Precharge. The disadvantage of the Precharge command is that it requires that the command and address busses be available at the appropriate time to issue the command. The advantage of the Precharge command is that it can be used to truncate bursts. Page 28 of 72 3/01 HYB25D256400/800T/AT 256-Mbit Double Data Rate SDRAM Write Command CK CK CKE HIGH CS RAS CAS WE x4: A0-A9, A11 x8: A0-A9 x16: A0-A8 CA EN AP A10 DIS AP BA0, BA1 BA CA = column address BA = bank address EN AP = enable Auto Precharge DIS AP = disable Auto Precharge Don’t Care Page 29 of 72 3/01 HYB25D256400/800T/AT 256-Mbit Double Data Rate SDRAM Write Burst (Burst Length = 4) Maximum DQSS T1 T2 T3 T4 CK CK Command Address Write NOP NOP NOP BA a, COL b tDQSS (max) DQS Dla-b DQ DM tQCK (max) tQOH(min) QFC (Optional) Minimum DQSS T1 T2 T3 T4 CK CK Command Address Write NOP NOP NOP BA a, COL b tDQSS (min) DQS DQ Dla-b DM tQCK(max) QFC tQOH(max) DI a-b = data in for bank a, column b. 3 subsequent elements of data in are applied in the programmed order following DI a-b. A non-interrupted burst is shown. A10 is Low with the Write command (Auto Precharge is disabled). QFC is an open drain driver. Its output high level is achieved through an externally connected pull up resistor connected to VDDQ. Don’t Care Page 30 of 72 3/01 HYB25D256400/800T/AT 256-Mbit Double Data Rate SDRAM Write to Write (Burst Length = 4) Maximum DQSS T1 T2 T3 T4 T5 T6 CK CK Command Address Write NOP Write BAa, COL b NOP NOP NOP BAa, COL n tDQSS (max) DQS DI a-b DQ DI a-n DM Minimum DQSS T1 T2 T3 T4 T5 T6 CK CK Command Address Write NOP BA, COL b Write NOP NOP NOP BA, COL n tDQSS (min) DQS DQ DI a-b DI a-n DM DI a-b = data in for bank a, column b, etc. 3 subsequent elements of data in are applied in the programmed order following DI a-b. 3 subsequent elements of data in are applied in the programmed order following DI a-n. A non-interrupted burst is shown. Each Write command may be to any bank. Page 31 of 72 Don’t Care 3/01 HYB25D256400/800T/AT 256-Mbit Double Data Rate SDRAM Write to Write: Max DQSS, Non-Consecutive (Burst Length = 4) T1 T2 T3 T4 T5 CK CK Command Address Write NOP NOP BAa, COL b Write NOP BAa, COL n tDQSS (max) DQS DQ DI a-b DI a-n DM DI a-b, etc. = data in for bank a, column b, etc. 3 subsequent elements of data in are applied in the programmed order following DI a-b. 3 subsequent elements of data in are applied in the programmed order following DI a-n. A non-interrupted burst is shown. Each Write command may be to any bank. Page 32 of 72 Don’t Care 3/01 HYB25D256400/800T/AT 256-Mbit Double Data Rate SDRAM Random Write Cycles (Burst Length = 2, 4 or 8) Maximum DQSS T1 T2 T3 T4 T5 CK CK Command Address Write Write BAa, COL b Write BAa, COL x Write BAa, COL n Write BAa, COL a BAa, COL g tDQSS (max) DQS DI a-b DQ DI a-b’ DI a-x DI a-x’ DI a-n DI a-n’ DI a-a DI a-a’ DM Minimum DQSS T1 T2 T3 T4 T5 CK CK Command Address Write Write BAa, COL b Write BAa, COL x Write BAa, COL n Write BAa, COL a BAa, COL g tDQSS (min) DQS DQ DI a-b DI a-b’ DI a-x DI a-x’ DI a-n DI a-n’ DI a-a DI a-a’ DI a-g DM DI a-b, etc. = data in for bank a, column b, etc. b’, etc. = odd or even complement of b, etc. (i.e., column address LSB inverted). Each Write command may be to any bank. Page 33 of 72 Don’t Care 3/01 HYB25D256400/800T/AT 256-Mbit Double Data Rate SDRAM Write to Read: Non-Interrupting (CAS Latency = 2; Burst Length = 4) Maximum DQSS T1 T2 T3 T4 T5 T6 CK CK Command Write NOP NOP NOP Read NOP tWTR Address BAa, COL b BAa, COL n CL = 2 tDQSS (max) DQS DI a-b DQ DM Minimum DQSS T1 T2 T3 T4 T5 T6 CK CK Command Write NOP NOP NOP Read NOP tWTR Address BAa, COL n BAa, COL b tDQSS (min) CL = 2 DQS DQ DI a-b DM DI a-b = data in for bank a, column b. 3 subsequent elements of data in are applied in the programmed order following DI a-b. A non-interrupted burst is shown. tWTR is referenced from the first positive CK edge after the last data in pair. A10 is Low with the Write command (Auto Precharge is disabled). The Read and Write commands may be to any bank. Page 34 of 72 Don’t Care 3/01 HYB25D256400/800T/AT 256-Mbit Double Data Rate SDRAM Write to Read: Interrupting (CAS Latency = 2; Burst Length = 8) Maximum DQSS T1 T2 T3 T4 T5 T6 CK CK Command Write NOP NOP NOP Read NOP tWTR Address BAa, COL n BAa, COL b CL = 2 tDQSS (max) DQS DIa- b DQ 1 DM 1 Minimum DQSS T1 T2 T3 T4 T5 T6 CK CK Command Write NOP NOP NOP Read NOP tWTR Address BAa, COL n BAa, COL b CL = 2 tDQSS (min) DQS DQ DI a-b DM 1 1 DI a-b = data in for bank a, column b. An interrupted burst is shown, 4 data elements are written. 3 subsequent elements of data in are applied in the programmed order following DI a-b. tWTR is referenced from the first positive CK edge after the last data in pair. The Read command masks the last 2 data elements in the burst. A10 is Low with the Write command (Auto Precharge is disabled). The Read and Write commands are not necessarily to the same bank. 1 = These bits are incorrectly written into the memory array if DM is low. Page 35 of 72 Don’t Care 3/01 HYB25D256400/800T/AT 256-Mbit Double Data Rate SDRAM Write to Read: Minimum DQSS, Odd Number of Data (3 bit Write), Interrupting (CAS Latency = 2; Burst Length = 8) T1 T2 T3 T4 T5 T6 CK CK Command Write NOP NOP NOP Read NOP tWTR Address BAa, COL n BAa, COL b CL = 2 tDQSS (min) DQS DQ DM DI a-b 1 2 2 DI a-b = data in for bank a, column b. An interrupted burst is shown, 3 data elements are written. 2 subsequent elements of data in are applied in the programmed order following DI a-b. tWTR is referenced from the first positive CK edge after the last desired data in pair (not the last desired data in element) The Read command masks the last 2 data elements in the burst. A10 is Low with the Write command (Auto Precharge is disabled). The Read and Write commands are not necessarily to the same bank. 1 = This bit is correctly written into the memory array if DM is low. Don’t Care 2 = These bits are incorrectly written into the memory array if DM is low. Page 36 of 72 3/01 HYB25D256400/800T/AT 256-Mbit Double Data Rate SDRAM Write to Read: Nominal DQSS, Interrupting (CAS Latency = 2; Burst Length = 8) T1 T2 T3 T4 T5 T6 CK CK Command Write NOP NOP NOP Read NOP tWTR Address BAa, COL n BAa, COL b CL = 2 tDQSS (nom) DQS DQ DI a-b DM 1 1 DI a-b = data in for bank a, column b. An interrupted burst is shown, 4 data elements are written. 3 subsequent elements of data in are applied in the programmed order following DI a-b. tWTR is referenced from the first positive CK edge after the last desired data in pair. The Read command masks the last 2 data elements in the burst. A10 is Low with the Write command (Auto Precharge is disabled). The Read and Write commands are not necessarily to the same bank. 1 = These bits are incorrectly written into the memory array if DM is low. Page 37 of 72 Don’t Care 3/01 HYB25D256400/800T/AT 256-Mbit Double Data Rate SDRAM Write to Precharge: Non-Interrupting (Burst Length = 4) Maximum DQSS T1 T2 T3 T4 T5 T6 CK CK Command Write NOP NOP NOP NOP PRE tWR Address BA (a or all) BA a, COL b tRP tDQSS (max) DQS DI a-b DQ DM Minimum DQSS T1 T2 T3 T4 T5 T6 CK CK Command Write NOP NOP NOP NOP PRE tWR Address BA (a or all) BA a, COL b tDQSS (min) tRP DQS DQ DI a-b DM DI a-b = data in for bank a, column b. 3 subsequent elements of data in are applied in the programmed order following DI a-b. A non-interrupted burst is shown. tWR is referenced from the first positive CK edge after the last data in pair. A10 is Low with the Write command (Auto Precharge is disabled). Page 38 of 72 Don’t Care 3/01 HYB25D256400/800T/AT 256-Mbit Double Data Rate SDRAM Write to Precharge: Interrupting (Burst Length = 4 or 8) Maximum DQSS T1 T2 T3 T4 T5 T6 CK CK Command Write NOP NOP NOP PRE NOP tWR Address BA (a or all) BA a, COL b tDQSS (max) tRP 2 DQS DQ DI a-b 3 DM 1 3 1 Minimum DQSS T1 T2 T3 T4 T5 T6 CK CK Command Write NOP NOP NOP PRE NOP tWR Address BA a, COL b BA (a or all) tDQSS (min) tRP 2 DQS DQ DM DI a-b 3 3 1 1 DI a-b = data in for bank a, column b. An interrupted burst is shown, 2 data elements are written. 1 subsequent element of data in is applied in the programmed order following DI a-b. tWR is referenced from the first positive CK edge after the last desired data in pair. The Precharge command masks the last 2 data elements in the burst, for burst length = 8. A10 is Low with the Write command (Auto Precharge is disabled). 1 = Can be don’t care for programmed burst length of 4. 2 = For programmed burst length of 4, DQS becomes don’t care at this point. 3 = These bits are incorrectly written into the memory array if DM is low. Page 39 of 72 Don’t Care 3/01 HYB25D256400/800T/AT 256-Mbit Double Data Rate SDRAM Write to Precharge: Minimum DQSS, Odd Number of Data (1 bit Write), Interrupting (Burst Length = 4 or 8) T1 T2 T3 T4 T5 T6 CK CK Command Write NOP NOP NOP PRE NOP tWR Address BA a, COL b BA (a or all) tDQSS (min) tRP 2 DQS DQ DM DI a-b 3 4 4 1 1 DI a-b = data in for bank a, column b. An interrupted burst is shown, 1 data element is written. tWR is referenced from the first positive CK edge after the last desired data in pair. The Precharge command masks the last 2 data elements in the burst. A10 is Low with the Write command (Auto Precharge is disabled). 1 = Can be don’t care for programmed burst length of 4. 2 = For programmed burst length of 4, DQS becomes don’t care at this point. 3 = This bit is correctly written into the memory array if DM is low. 4 = These bits are incorrectly written into the memory array if DM is low. Page 40 of 72 Don’t Care 3/01 HYB25D256400/800T/AT 256-Mbit Double Data Rate SDRAM Write to Precharge: Nominal DQSS (2 bit Write), Interrupting (Burst Length = 4 or 8) T1 T2 T3 T4 T5 T6 CK CK Command Write NOP NOP NOP PRE NOP tWR BA (a or all) BA a, COL b Address tDQSS (nom) tRP 2 DQS DQ DM DI a-b 3 3 1 1 DI a-b = Data In for bank a, column b. An interrupted burst is shown, 2 data elements are written. 1 subsequent element of data in is applied in the programmed order following DI a-b. tWR is referenced from the first positive CK edge after the last desired data in pair. The Precharge command masks the last 2 data elements in the burst. A10 is Low with the Write command (Auto Precharge is disabled). 1 = Can be don’t care for programmed burst length of 4. 2 = For programmed burst length of 4, DQS becomes don’t care at this point. 3 = These bits are incorrectly written into the memory array if DM is low. Page 41 of 72 Don’t Care 3/01 HYB25D256400/800T/AT 256-Mbit Double Data Rate SDRAM Precharge Command CK CK CKE HIGH CS RAS CAS WE A0-A9, A11, A12 All Banks A10 BA0, BA1 One Bank BA BA = bank address (if A10 is Low, otherwise Don’t Care). Don’t Care Precharge The Precharge command is used to deactivate the open row in a particular bank or the open row in all banks. The bank(s) will be available for a subsequent row access some specified time (tRP) after the Precharge command is issued. Input A10 determines whether one or all banks are to be precharged, and in the case where only one bank is to be precharged, inputs BA0, BA1 select the bank. When all banks are to be precharged, inputs BA0, BA1 are treated as “Don’t Care.” Once a bank has been precharged, it is in the idle state and must be activated prior to any Read or Write commands being issued to that bank. Page 42 of 72 3/01 HYB25D256400/800T/AT 256-Mbit Double Data Rate SDRAM Power-Down Power-down is entered when CKE is registered LOW (no accesses can be in progress). If power-down occurs when all banks are idle, 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. Entering power-down deactivates the input and output buffers, excluding CK, CK and CKE. The DLL is still running in Power Down mode, so for maximum power savings, the user has the option of disabling the DLL prior to entering Powerdown. In that case, the DLL must be enabled after exiting power-down, and 200 clock cycles must occur before a Read command can be issued. In power-down mode, CKE Low and a stable clock signal must be maintained at the inputs of the DDR SDRAM, and all other input signals are “Don’t Care”. However, powerdown duration is limited by the refresh requirements of the device, so in most applications, the self refresh mode is preferred over the DLL-disabled power-down mode. The power-down state is synchronously exited when CKE is registered HIGH (along with a Nop or Deselect command). A valid, executable command may be applied one clock cycle later. Power Down CK CK tIS CKE Command VALID NOP No column access in progress Enter Power Down mode (Burst Read or Write operation must not be in progress) Page 43 of 72 tIS NOP VALID Exit power down mode Don’t Care 3/01 HYB25D256400/800T/AT 256-Mbit Double Data Rate SDRAM Truth Table 2: Clock Enable (CKE) 1. 2. 3. 4. CKEn is the logic state of CKE at clock edge n: CKE n-1 was the state of CKE at the previous clock edge. Current state is the state of the DDR SDRAM immediately prior to clock edge n. COMMAND n is the command registered at clock edge n, and ACTION n is a result of COMMAND n. All states and sequences not shown are illegal or reserved. CKE n-1 CKEn Current State Previous Cycle Current Cycle Command n Self Refresh L L X Self Refresh L H Deselect or NOP Power Down L L X Power Down L H Deselect or NOP Exit Power-Down All Banks Idle H L Deselect or NOP Precharge Power-Down Entry All Banks Idle H L AUTO REFRESH Self Refresh Entry Bank(s) Active H L Deselect or NOP Active Power-Down Entry H H See “Truth Table 3: Current State Bank n - Command to Bank n (Same Bank)” on page 45 Action n Notes Maintain Self-Refresh Exit Self-Refresh 1 Maintain Power-Down 1. Deselect or NOP commands should be issued on any clock edges occurring during the Self Refresh Exit (tXSNR) period. A minimum of 200 clock cycles are needed before applying a read command to allow the DLL to lock to the input clock. Page 44 of 72 3/01 HYB25D256400/800T/AT 256-Mbit Double Data Rate SDRAM Truth Table 3: Current State Bank n - Command to Bank n (Same Bank) (Part 1 of 2) Current State CS RAS CAS WE Command H X X X Deselect NOP. Continue previous operation Action Notes 1-6 L H H H No Operation NOP. Continue previous operation 1-6 L L H H Active Select and activate row 1-6 L L L H AUTO REFRESH 1-7 L L L L MODE REGISTER SET 1-7 L H L H Read Select column and start Read burst 1-6, 10 L H L L Write Select column and start Write burst 1-6, 10 L L H L Precharge Deactivate row in bank(s) 1-6, 8 L H L H Read Select column and start new Read burst 1-6, 10 L L H L Precharge Truncate Read burst, start Precharge 1-6, 8 L H H L BURST TERMINATE BURST TERMINATE 1-6, 9 Any Idle Row Active Read (Auto Precharge Disabled) 1. This table applies when CKE n-1 was HIGH and CKE n is HIGH (see Truth Table 2: Clock Enable (CKE) and after tXSNR / tXSRD has been met (if the previous state was self refresh). 2. This table is bank-specific, except where noted, i.e., the current state is for a specific bank and the commands shown are those allowed to be issued to that bank when in that state. Exceptions are covered in the notes below. 3. Current state definitions: Idle: The bank has been precharged, and tRP has been met. Row Active: A row in the bank has been activated, and tRCD has been met. No data bursts/accesses and no register accesses are in progress. Read: A Read burst has been initiated, with Auto Precharge disabled, and has not yet terminated or been terminated. Write: A Write burst has been initiated, with Auto Precharge disabled, and has not yet terminated or been terminated. 4. The following states must not be interrupted by a command issued to the same bank. Precharging: Starts with registration of a Precharge command and ends when tRP is met. Once tRP is met, the bank is in the idle state. Row Activating: Starts with registration of an Active command and ends when tRCD is met. Once tRCD is met, the bank is in the “row active” state. Read w/Auto Precharge Enabled: Starts with registration of a Read command with Auto Precharge enabled and ends when tRP has been met. Once tRP is met, the bank is in the idle state. Write w/Auto Precharge Enabled: Starts with registration of a Write command with Auto Precharge enabled and ends when tRP has been met. Once tRP is met, the bank is in the idle state. Deselect or NOP commands, or allowable commands to the other bank should be issued on any clock edge occurring during these states. Allowable commands to the other bank are determined by its current state and according to Truth Table 4. 5. The following states must not be interrupted by any executable command; Deselect or NOP commands must be applied on each positive clock edge during these states. Refreshing: Starts with registration of an Auto Refresh command and ends when tRFC is met. Once tRFC is met, the DDR SDRAM is in the “all banks idle” state. Accessing Mode Register: Starts with registration of a Mode Register Set command and ends when tMRD has been met. Once tMRD is met, the DDR SDRAM is in the “all banks idle” state. Precharging All: Starts with registration of a Precharge All command and ends when tRP is met. Once tRP is met, all banks is in the idle state. 6. All states and sequences not shown are illegal or reserved. 7. Not bank-specific; requires that all banks are idle. 8. May or may not be bank-specific; if all/any banks are to be precharged, all/any must be in a valid state for precharging. 9. Not bank-specific; BURST TERMINATE affects the most recent Read burst, regardless of bank. 10. Reads or Writes listed in the Command/Action column include Reads or Writes with Auto Precharge enabled and Reads or Writes with Auto Precharge disabled. 11. Requires appropriate DM masking. Page 45 of 72 3/01 HYB25D256400/800T/AT 256-Mbit Double Data Rate SDRAM Truth Table 3: Current State Bank n - Command to Bank n (Same Bank) (Part 2 of 2) Current State Write (Auto Precharge Disabled) CS RAS CAS WE Command Action L H L H Read Select column and start Read burst 1-6, 10, 11 L H L L Write Select column and start Write burst 1-6, 10 L L H L Precharge Truncate Write burst, start Precharge Notes 1-6, 8, 11 1. This table applies when CKE n-1 was HIGH and CKE n is HIGH (see Truth Table 2: Clock Enable (CKE) and after tXSNR / tXSRD has been met (if the previous state was self refresh). 2. This table is bank-specific, except where noted, i.e., the current state is for a specific bank and the commands shown are those allowed to be issued to that bank when in that state. Exceptions are covered in the notes below. 3. Current state definitions: Idle: The bank has been precharged, and tRP has been met. Row Active: A row in the bank has been activated, and tRCD has been met. No data bursts/accesses and no register accesses are in progress. Read: A Read burst has been initiated, with Auto Precharge disabled, and has not yet terminated or been terminated. Write: A Write burst has been initiated, with Auto Precharge disabled, and has not yet terminated or been terminated. 4. The following states must not be interrupted by a command issued to the same bank. Precharging: Starts with registration of a Precharge command and ends when tRP is met. Once tRP is met, the bank is in the idle state. Row Activating: Starts with registration of an Active command and ends when tRCD is met. Once tRCD is met, the bank is in the “row active” state. Read w/Auto Precharge Enabled: Starts with registration of a Read command with Auto Precharge enabled and ends when tRP has been met. Once tRP is met, the bank is in the idle state. Write w/Auto Precharge Enabled: Starts with registration of a Write command with Auto Precharge enabled and ends when tRP has been met. Once tRP is met, the bank is in the idle state. Deselect or NOP commands, or allowable commands to the other bank should be issued on any clock edge occurring during these states. Allowable commands to the other bank are determined by its current state and according to Truth Table 4. 5. The following states must not be interrupted by any executable command; Deselect or NOP commands must be applied on each positive clock edge during these states. Refreshing: Starts with registration of an Auto Refresh command and ends when tRFC is met. Once tRFC is met, the DDR SDRAM is in the “all banks idle” state. Accessing Mode Register: Starts with registration of a Mode Register Set command and ends when tMRD has been met. Once tMRD is met, the DDR SDRAM is in the “all banks idle” state. Precharging All: Starts with registration of a Precharge All command and ends when tRP is met. Once tRP is met, all banks is in the idle state. 6. All states and sequences not shown are illegal or reserved. 7. Not bank-specific; requires that all banks are idle. 8. May or may not be bank-specific; if all/any banks are to be precharged, all/any must be in a valid state for precharging. 9. Not bank-specific; BURST TERMINATE affects the most recent Read burst, regardless of bank. 10. Reads or Writes listed in the Command/Action column include Reads or Writes with Auto Precharge enabled and Reads or Writes with Auto Precharge disabled. 11. Requires appropriate DM masking. Page 46 of 72 3/01 HYB25D256400/800T/AT 256-Mbit Double Data Rate SDRAM Truth Table 4: Current State Bank n - Command to Bank m (Different bank) (Part 1 of 2) Current State CS RAS CAS WE Command Action Notes H X X X Deselect NOP/continue previous operation 1-6 L H H H No Operation NOP/continue previous operation 1-6 X X X X Any Command Otherwise Allowed to Bank m L L H H Active Select and activate row 1-6 L H L H Read Select column and start Read burst 1-7 L H L L Write Select column and start Write burst 1-7 L L H L Precharge L L H H Active Select and activate row 1-6 L H L H Read Select column and start new Read burst 1-7 L L H L Precharge L L H H Active Select and activate row 1-6 L H L H Read Select column and start Read burst 1-8 L H L L Write Select column and start new Write burst 1-7 L L H L Precharge L L H H Active Select and activate row L H L H Read Select column and start new Read burst L H L L Write Select column and start Write burst L L H L Precharge Any Idle Row Activating, Active, or Precharging Read (Auto Precharge Disabled) Write (Auto Precharge Disabled) Read (With Auto Precharge) 1-6 1-6 1-6 1-6 1-6 1-7,10 1-7,9,10 1-6 1. This table applies when CKE n-1 was HIGH and CKE n is HIGH (see Truth Table 2: Clock Enable (CKE) and after tXSNR / tXSRD has been met (if the previous state was self refresh). 2. This table describes alternate bank operation, except where noted, i.e., the current state is for bank n and the commands shown are those allowed to be issued to bank m (assuming that bank m is in such a state that the given command is allowable). Exceptions are covered in the notes below. 3. Current state definitions: Idle: The bank has been precharged, and tRP has been met. Row Active: A row in the bank has been activated, and tRCD has been met. No data bursts/accesses and no register accesses are in progress. Read: A Read burst has been initiated, with Auto Precharge disabled, and has not yet terminated or been terminated. Write: A Write burst has been initiated, with Auto Precharge disabled, and has not yet terminated or been terminated. Read with Auto Precharge Enabled: See note 10. Write with Auto Precharge Enabled: See note 10. 4. AUTO REFRESH and Mode Register Set commands may only be issued when all banks are idle. 5. A BURST TERMINATE command cannot be issued to another bank; it applies to the bank represented by the current state only. 6. All states and sequences not shown are illegal or reserved. 7. Reads or Writes listed in the Command/Action column include Reads or Writes with Auto Precharge enabled and Reads or Writes with Auto Precharge disabled. 8. Requires appropriate DM masking. 9. A Write command may be applied after the completion of data output. 10. Concurrent Auto Precharge: This device supports “Concurrent Auto Precharge”. When a read with auto precharge or a write with auto precharge is enabled any command may follow to the other banks as long as that command does not interrupt the read or write data transfer and all other limitations apply (e.g. contention between READ data and WRITE data must be avoided). The mimimum delay from a read or write command with auto precharge enable, to a command to a different banks is summarized in table 4a. Page 47 of 72 3/01 HYB25D256400/800T/AT 256-Mbit Double Data Rate SDRAM Truth Table 4: Current State Bank n - Command to Bank m (Different bank) (Part 2 of 2) Current State Write (With Auto Precharge) CS RAS CAS WE Command Action Notes L L H H Active Select and activate row L H L H Read Select column and start Read burst 1-7,10 L H L L Write Select column and start new Write burst 1-7,10 L L H L Precharge 1-6 1-6 1. This table applies when CKE n-1 was HIGH and CKE n is HIGH (see Truth Table 2: Clock Enable (CKE) and after tXSNR / tXSRD has been met (if the previous state was self refresh). 2. This table describes alternate bank operation, except where noted, i.e., the current state is for bank n and the commands shown are those allowed to be issued to bank m (assuming that bank m is in such a state that the given command is allowable). Exceptions are covered in the notes below. 3. Current state definitions: Idle: The bank has been precharged, and tRP has been met. Row Active: A row in the bank has been activated, and tRCD has been met. No data bursts/accesses and no register accesses are in progress. Read: A Read burst has been initiated, with Auto Precharge disabled, and has not yet terminated or been terminated. Write: A Write burst has been initiated, with Auto Precharge disabled, and has not yet terminated or been terminated. Read with Auto Precharge Enabled: See note 10. Write with Auto Precharge Enabled: See note 10. 4. AUTO REFRESH and Mode Register Set commands may only be issued when all banks are idle. 5. A BURST TERMINATE command cannot be issued to another bank; it applies to the bank represented by the current state only. 6. All states and sequences not shown are illegal or reserved. 7. Reads or Writes listed in the Command/Action column include Reads or Writes with Auto Precharge enabled and Reads or Writes with Auto Precharge disabled. 8. Requires appropriate DM masking. 9. A Write command may be applied after the completion of data output. 10. Concurrent Auto Precharge: This device supports “Concurrent Auto Precharge”. When a read with auto precharge or a write with auto precharge is enabled any command may follow to the other banks as long as that command does not interrupt the read or write data transfer and all other limitations apply (e.g. contention between READ data and WRITE data must be avoided). The mimimum delay from a read or write command with auto precharge enable, to a command to a different banks is summarized in table 4a. Truth Table 4a : Concurrent Auto Precharge: From Command WRITE w/AP Minimum Delay with Concurrent Auto Precharge Support Units Read or Read w/AP 1 + (BL/2) + tWTR tCK Write ot Write w/AP BL/2 tCK 1 tCK Read or Read w/AP BL/2 tCK Write or Write w/AP CL (rounded up)+ BL/2 tCK 1 tCK To Command (different bank) Precharge or Activate Read w/AP Precharge or Activate Page 48 of 72 3/01 HYB25D256400/800T/AT 256-Mbit Double Data Rate SDRAM Simplified State Diagram Power Applied Power On Self Refresh Precharge PREALL REFS REFSX MRS EMRS MRS Auto Refresh REFA Idle CKEL CKEH Active Power Down ACT Precharge Power Down CKEH CKEL Burst Stop Row Active Write Write A Write Read Read A Read Read Read A Write A Read A PRE Write A PRE PRE PRE Read A Precharge PREALL Automatic Sequence Command Sequence PREALL = Precharge All Banks MRS = Mode Register Set EMRS = Extended Mode Register Set REFS = Enter Self Refresh REFSX = Exit Self Refresh REFA = Auto Refresh Page 49 of 72 CKEL = Enter Power Down CKEH = Exit Power Down ACT = Active Write A = Write with Autoprecharge Read A = Read with Autoprecharge PRE = Precharge 3/01 HYB25D256400/800T/AT 256-Mbit Double Data Rate SDRAM Absolute Maximum Ratings Symbol VIN , VOUT VIN VDD VDDQ TA TSTG PD IOUT Parameter Rating Units −0.5 to VDDQ+ 0.5 V Voltage on Inputs relative to VSS −0.5 to +3.6 V Voltage on VDD supply relative to VSS −0.5 to +3.6 V Voltage on VDDQ supply relative to VSS −0.5 to +3.6 V 0 to +70 °C −55 to +150 °C Power Dissipation 1.0 W Short Circuit Output Current 50 mA Voltage on I/O pins relative to VSS Operating Temperature (Ambient) Storage Temperature (Plastic) Note: Stresses greater than those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. This is a stress rating only, and functional operation of the device at these or any other conditions above those indicated in the operational sections of this specification is not implied. Exposure to absolute maximum rating conditions for extended periods may affect reliability. Page 50 of 72 3/01 HYB25D256400/800T/AT 256-Mbit Double Data Rate SDRAM Capacitance Symbol Min. Max. Units Notes Input Capacitance: CK, CK Parameter CI1 2.0 3.0 pF 1 ,3 Input Capacitance: All other input-only pins (except DM) CI2 2.0 3.0 pF 1, 3 Input/Output Capacitance: DQ, DQS, DM CIO 4.0 5.0 pF 1, 2, 3 Output Capacitance: QFC CO1 2.0 4.0 pF 1, 3 Delta Input capacitance for DQ, DQS, DM ∆C - 0.5 pF 3 Delta Input capacitance for CK, CK ∆C - 0.25 pF 3 1. VDDQ = VDD = 2.5V ± 0.2V, f = 100MHz, TA = 25°C, VOUT (DC) = VDDQ/2, VOUT (Peak to Peak) = 0.2V. 2. DM inputs are grouped with I/O pins reflecting the fact that they are matched in loading to DQ and DQS to facilitate trace matching at the board level. 3. All capacitances are guaranteed by design and are tested on a samples basis only. Electrical Characteristics and DC Operating Conditions (0°C ≤ TA ≤ 70°C; VDDQ = 2.5V ± 0.2V, VDD = + 2.5V ± 0.2V, see AC Characteristics) Symbol Min Max Units Notes Supply Voltage 2.3 2.7 V 1 I/O Supply Voltage 2.3 2.7 V 1 VSS, VSSQ Supply Voltage, I/O Supply Voltage 0 0 V I/O Reference Voltage 0.49 x VDDQ 0.51 x VDDQ V 1, 2 I/O Termination Voltage (System) VREF − 0.04 VREF + 0.04 V 1, 3 VIH(DC) Input High (Logic1) Voltage VREF + 0.15 VDDQ + 0.3 V 1 VIL(DC) Input Low (Logic0) Voltage − 0.3 VREF − 0.15 V 1 VIN(DC) Input Voltage Level, CK and CK Inputs − 0.3 VDDQ + 0.3 V 1 VID(DC) Input Differential Voltage, CK and CK Inputs 0.3 VDDQ + 0.6 V 1, 4 VIRatio VI-Matching Pullup Current to Pulldown Current 0.71 1.4 II Input Leakage Current Any input 0V ≤ VIN ≤ VDD (All other pins not under test = 0V) −2 2 µA 1 IOZ Output Leakage Current (DQs are disabled; 0V ≤ Vout ≤ VDDQ) −5 5 µA 1 IOH Output High Current, Normal Strength Driver (VOUT = V DDQ - 0.373V, min VREF,min VTT) − 16.8 mA 1 IOL Output Low Current, Normal Strength Driver (VOUT = 0.373V, max VREF, max. VTT) 16.8 mA 1 V DD VDDQ VREF VTT Parameter 5 1. Inputs are not recognized as valid until VREF stabilizes. 2. V REF is expected to be equal to 0.5 V DDQ of the transmitting device, and to track variations in the DC level of the same. Peak-topeak noise on VREF may not exceed ± 2% of the DC value. 3. V TT is not applied directly to the device. VTT is a system supply for signal termination resistors, is expected to be set equal to VREF, and must track variations in the DC level of VREF. 4. VID is the magnitude of the difference between the input level on CK and the input level on CK. 5. The ration of the pullup current to the pulldown current is specified for the same temperature and voltage, over the entire temperature and voltage range, for device drain to source voltage from 0.25 to 1.0V. For a given output, it represents the maximum difference between pullup and pulldown drivers due to process variation. Page 51 of 72 3/01 HYB25D256400/800T/AT 256-Mbit Double Data Rate SDRAM Pulldown and Pullup Characteristics 1. The nominal pulldown V-I curve for DDR SDRAM devices is expected, but not guaranteed, to lie within the inner bounding lines of the V-I curve. 2. The full variation in driver pulldown current from minimum to maximum process, temperature, and voltage lie within the outer bounding lines of the V-I curve. Pulldown Characteristics 140 Maximum 1OUT (mA) 120 100 Nominal High 80 60 Nominal Low 40 Minimum 20 0 0 0.5 1 1.5 2 2.5 VOUT (V) 3. The nominal pullup V-I curve for DDR SDRAM devices is expected, but not guaranteed, to lie within the inner bounding lines of the V-I curve. 4. The full variation in driver pullup current from minimum to maximum process, temperature, and voltage lie within the outer bounding lines of the V-I curve. Pullup Characteristics 0 -20 Minimum 1OUT (mA) -40 Nominal Low -60 -80 -100 -120 -140 Nominal High -160 Maximum 0 0.5 1 1.5 VOUT (V) 2 2.5 5. The full variation in the ratio of the maximum to minimum pullup and pulldown current does not exceed 1.7, for device drain to source voltages from 0.1 to 1.0. 6. The full variation in the ratio of the nominal pullup to pulldown current should be unity ± 10%, for device drain to source voltages from 0.1 to 1.0V. Page 52 of 72 3/01 HYB25D256400/800T/AT 256-Mbit Double Data Rate SDRAM Pulldown and Pullup Currents Pulldown Current (mA) Pullup Current (mA) Voltage (V) Nominal Low Nominal High Min Max Nominal Low Nominal High Min Max 0.1 6.0 6.8 4.6 9.6 −6.1 −7.6 −4.6 −10.0 0.2 12.2 13.5 9.2 18.2 −12.2 −14.5 −9.2 −20.0 0.3 18.1 20.1 13.8 26.0 −18.1 −21.2 −13.8 −29.8 0.4 24.1 26.6 18.4 33.9 −24.0 −27.7 −18.4 −38.8 0.5 29.8 33.0 23.0 41.8 −29.8 −34.1 −23.0 −46.8 0.6 34.6 39.1 27.7 49.4 −34.3 −40.5 −27.7 −54.4 0.7 39.4 44.2 32.2 56.8 −38.1 −46.9 −32.2 −61.8 0.8 43.7 49.8 36.8 63.2 −41.1 −53.1 −36.0 −69.5 0.9 47.5 55.2 39.6 69.9 −43.8 −59.4 −38.2 −77.3 1.0 51.3 60.3 42.6 76.3 −46.0 −65.5 −38.7 −85.2 1.1 54.1 65.2 44.8 82.5 −47.8 −71.6 −39.0 −93.0 1.2 56.2 69.9 46.2 88.3 −49.2 −77.6 −39.2 −100.6 1.3 57.9 74.2 47.1 93.8 −50.0 −83.6 −39.4 −108.1 1.4 59.3 78.4 47.4 99.1 −50.5 −89.7 −39.6 −115.5 1.5 60.1 82.3 47.7 103.8 −50.7 −95.5 −39.9 −123.0 1.6 60.5 85.9 48.0 108.4 −51.0 −101.3 −40.1 −130.4 1.7 61.0 89.1 48.4 112.1 −51.1 −107.1 −40.2 −136.7 1.8 61.5 92.2 48.9 115.9 −51.3 −112.4 −40.3 −144.2 1.9 62.0 95.3 49.1 119.6 −51.5 −118.7 −40.4 −150.5 2.0 62.5 97.2 49.4 123.3 −51.6 −124.0 −40.5 −156.9 2.1 62.9 99.1 49.6 126.5 −51.8 −129.3 −40.6 −163.2 2.2 63.3 100.9 49.8 129.5 −52.0 −134.6 −40.7 −169.6 2.3 63.8 101.9 49.9 132.4 −52.2 −139.9 −40.8 −176.0 2.4 64.1 102.8 50.0 135.0 −52.3 −145.2 −40.9 −181.3 2.5 64.6 103.8 50.2 137.3 −52.5 −150.5 −41.0 −187.6 2.6 64.8 104.6 50.4 139.2 -52.7 -155.3 -41.1 -192.9 2.7 65.0 105.4 50.5 140.8 -52.8 -160.1 -41.2 -198.2 Pulldown and Pullup Process Variations and Conditions Nominal Minimum Maximum Operating Temperature 25 °C 0 °C 70 °C VDD / VDDQ 2.5V 2.3V 2.7V The above characteristics are specified under best, worst, and nominal process variations / conditions. Page 53 of 72 3/01 HYB25D256400/800T/AT 256-Mbit Double Data Rate SDRAM AC Characteristics (Notes 1-5 apply to the following Tables; Electrical Characteristics and DC Operating Conditions, AC Operating Conditions, IDD Specifications and Conditions, and Electrical Characteristics and AC Timing.) 1. All voltages referenced to VSS. 2. Tests for AC timing, IDD, and electrical, AC and DC characteristics, may be conducted at nominal reference/supply voltage levels, but the related specifications and device operation are guaranteed for the full voltage range specified. 3. The figure below represents the timing reference load used indefining the relevant timing parameters of the part. It is not intended to be either a precise representation of the typical system environment nor a depiction of the actual load presented by a production tester. System designers will us IBIS or other simulation tools to correlate the timing reference load to a system environment. Manufacturers will correlate to their production test conditions (generally a coaxial transmission line terminated at the tester electronics). 4. AC timing and IDD tests may use a VIL to VIH swing of up to 1.5V in the test environment, but input timing is still referenced to VREF (or to the crossing point for CK, CK), and parameter specifications are guaranteed for the specified AC input levels under normal use conditions. The minimum slew rate for the input signals is 1V/ns in the range between VIL(AC) and VIH(AC). 5. The AC and DC input level specifications are as defined in the SSTL_2 Standard (i.e. the receiver effectively switches as a result of the signal crossing the AC input level, and remains in that state as long as the signal does not ring back above (below) the DC input LOW (HIGH) level. 6. For DDR SDRAM AC Overshoot / Undershoot Specification see JEDEC ballot JC-42.3-00-121, jcb-00-083,ltem 193B For DQ / DM /DQS input slew rate see JEDEC ballot JC-42.3-00-177, JCB-00-085, Item 1178.09 For I/O Delta Rise / Fall Derating see JEDEC ballot JC-42.3-00-208, JCB-00-088, Item 1178.13 For general standardization of DDR SDRAM lew rate see JEDEC ballot JC-42.3-00-117, JCB-00-089, Item 1091B AC Output Load Circuit Diagram / Timing Reference Load VTT 50Ω Output (VOUT) Timing Reference Point 30pF Page 54 of 72 3/01 HYB25D256400/800T/AT 256-Mbit Double Data Rate SDRAM AC Operating Conditions (0 °C ≤ TA ≤ 70 °C; VDDQ = 2.5V ± 0.2V; VDD = 2.5V ± 0.2V, See AC Characteristics) Symbol Parameter/Condition VIH(AC) Input High (Logic 1) Voltage, DQ, DQS, and DM Signals VIL(AC) Input Low (Logic 0) Voltage, DQ, DQS, and DM Signals VID(AC) Input Differential Voltage, CK and CK Inputs VIX(AC) Input Closing Point Voltage, CK and CK Inputs 1. 2. 3. 4. Min Max Unit Notes V 1, 2 VREF − 0.31 V 1, 2 VDDQ + 0.6 V 1, 2, 3 V 1, 2, 4 VREF + 0.31 0.62 0.5*V DDQ − 0.2 0.5*VDDQ + 0.2 Input slew rate = 1V/ns. Inputs are not recognized as valid until VREF stabilizes. VID is the magnitude of the difference between the input level on CK and the input level on CK. The value of VIX is expected to equal 0.5*V DDQ of the transmitting device and must track variations in the DC level of the same. IDD Specifications and Conditions (0 °C ≤ TA ≤ 70 °C; VDDQ = 2.5V ± 0.2V; VDD = 2.5V ± 0.2V, See AC Characteristics) Symbol Parameter/Condition DDR266 DDR200 Unit Notes IDD0 Operating Current: one bank; active / precharge; tRC = tRC MIN; tCK = tCK MIN ; DQ, DM, and DQS inputs changing twice per clock cycle; address and control inputs changing once per clock cycle 100 90 mA 1, 2 IDD1 Operating Current: one bank; active / read / precharge; Burst = 2; tRC = tRC MIN ; CL = 2.5; tCK = tCK MIN ; IOUT = 0mA; address and control inputs changing once per clock cycle 120 100 mA 1, 2 IDD2P Precharge Power-Down Standby Current: all banks idle; power-down mode; CKE ≤ V IL MAX; tCK = tCK MIN 20 15 mA 1, 2 IDD2N Idle Standby Current: CS ≥ V IH MIN; all banks idle; CKE ≥ V IH MIN; tCK = tCK MIN; address and control inputs changing once per clock cycle 40 35 mA 1, 2 IDD3P Active Power-Down Standby Current: one bank active; power-down mode; CKE ≤ V IL MAX; tCK = tCK MIN 20 15 mA 1, 2 IDD3N Active Standby Current: one bank; active / precharge;CS ≥ VIH MIN ; CKE ≥ V IH MIN ; tRC = tRAS MAX; tCK = tCK MIN; DQ, DM, and DQS inputs changing twice per clock cycle; address and control inputs changing once per clock cycle 70 60 mA 1, 2 IDD4R Operating Current: one bank; Burst = 2; reads; continuous burst; address and control inputs changing once per clock cycle; DQ and DQS outputs changing twice per clock cycle; CL = 2.5; tCK = tCK MIN; IOUT = 0mA 190 150 mA 1, 2 IDD4W Operating Current: one bank; Burst = 2; writes; continuous burst; address and control inputs changing once per clock cycle; DQ and DQS inputs changing twice per clock cycle; CL = 2.5; tCK = tCK MIN 170 130 mA 1, 2 IDD5 Auto-Refresh Current: tRC = tRFC MIN 190 180 mA 1, 2 IDD6 Self-Refresh Current: CKE ≤ 0.2V 3 3 mA 1, 2, 3 IDD7 Operating Current: four bank; four bank interleaving with BL=4, address and control inputs randomly changing; 50% of data changing at every transfer; tRC = tRC MIN; I OUT = 0mA 325 250 mA 1 1. IDD specifications are tested after the device is properly initialized and measured at 100 Mhz for DDR200 and 133 MHz for DDR266 2. Input slew rate = 1V/ns. 3. Enables on-chip refresh and address counters. Page 55 of 72 3/01 HYB25D256400/800T/AT 256-Mbit Double Data Rate SDRAM Electrical Characteristics & AC Timing for DDR266/DDR200 - Absolute Specifications (0 °C ≤ TA ≤ 70 °C; VDDQ = 2.5V ± 0.2V; VDD = 2.5V ± 0.2V, See AC Characteristics) (Part 1 of 3) Symbol tAC DDR266A -7 Parameter DQ output access time from CK/CK tDQSCK DQS output access time from CK/CK DDR266B -7.5 DDR200 -8 Unit Notes Min Max Min Max Min Max − 0.75 + 0.75 − 0.75 + 0.75 − 0.8 + 0.8 ns 1-4 − 0.75 + 0.75 − 0.75 + 0.75 − 0.8 + 0.8 ns 1-4 tCH CK high-level width 0.45 0.55 0.45 0.55 0.45 0.55 tCK 1-4 tCL CK low-level width 0.45 0.55 0.45 0.55 0.45 0.55 tCK 1-4 tHP Clock Half Period ns 1-4 tCK min (tCL, tCH) min (tCL, tCH) min (tCL, tCH) CL = 2.5 7 25 7.5 12 8 12 ns 1-4 CL = 2.0 7.5 12 8 12 10 12 ns 1-4 Clock cycle time tCK tDH DQ and DM input hold time 0.5 0.5 0.6 ns 1-4 tDS DQ and DM input setup time 0.5 0.5 0.6 ns 1-4 tIPW Control and Addr. input pulse width (each input) 2.2 2.2 2.5 ns 1-, 12 DQ and DM input pulse width (each input) 1.75 1.75 2 ns 1-4,12 tDIPW tHZ Data-out high-impedence time from CK/CK − 0.75 + 0.75 − 0.75 + 0.75 − 0.8 + 0.8 ns 1-4, 5 tLZ Data-out low-impedence time from CK/CK − 0.75 + 0.75 − 0.75 + 0.75 − 0.8 + 0.8 ns 1-4, 5 0.75 1.25 0.75 1.25 0.75 1.25 tCK 1-4 tDQSS Write command to 1st DQS latching transition tDQSQ DQS-DQ skew (for DQS & associated DQ signals) + 0.5 + 0.5 + 0.6 ns 1-4 tQHS Data hold skew factor + 0.75 + 0.75 + 1.0 ns 1-4 tQH Data Output hold time from DQS tDQSL,H DQS input low (high) pulse width (write cycle) tHP-tQHS tHP-tQHS tHP-tQHS ns 1-4 0.35 0.35 0.35 tCK 1-4 1. Input slew rate >=1V/ns for DDR266 and = 1V/ns for DDR200. 2. The CK/CK input reference level (for timing reference to CK/CK) is the point at which CK and CK cross: the input reference level for signals other than CK/CK, is VREF. CK/CK slew rate are >= 1.0 V/ns. 3. Inputs are not recognized as valid until VREF stabilizes. 4. The Output timing reference level, as measured at the timing reference point indicated in AC Characteristics (Note 3) is VTT. 5. tHZ and tLZ transitions occur in the same access time windows as valid data transitions. These parameters are not referred to a specific voltage level, but specify when the device is no longer driving (HZ), or begins driving (LZ). 6. The maximum limit for this parameter is not a device limit. The device operates with a greater value for this parameter, but system performance (bus turnaround) degrades accordingly. 7. The specific requirement is that DQS be valid (HIGH, LOW, or some point on a valid transition) on or before this CK edge. A valid transition is defined as monotonic and meeting the input slew rate specifications of the device. When no writes were previously in progress on the bus, DQS will be transitioning from Hi-Z to logic LOW. If a previous write was in progress, DQS could be HIGH, LOW, or transitioning from HIGH to LOW at this time, depending on tDQSS. 8. A maximum of eight Autorefresh commands can be posted to any given DDR SDRAM device. 9. QFC is enabled as soon as possible after the rising CK edge that registers the Write command. 10. QFC is disabled as soon as possible after the last valid DQS edge transitions Low. 11. For each of the terms, if not already an integer, round to the next highest integer. tCK is equal to the actual system clock cycle time. 12. These parameters guarantee device timing, but they are not necessarily tested on each device 13. Fast slew rate >= 1 V/ns, slow slew rate >= 0.5V/ns. For input setup & holdtime derating for slew rates less than 0.5 V/ns see JEDEC ballot JC-423-00-210, JCB-00-087, Item 1178.10 Page 56 of 72 3/01 HYB25D256400/800T/AT 256-Mbit Double Data Rate SDRAM Electrical Characteristics & AC Timing for DDR266/DDR200 - Absolute Specifications (0 °C ≤ TA ≤ 70 °C; VDDQ = 2.5V ± 0.2V; VDD = 2.5V ± 0.2V, See AC Characteristics) (Part 2 of 3) Symbol Parameter DDR266A -7 Min Max DDR266B -7.5 Min Max DDR200 -8 Min Unit Notes Max tDSS DQS falling edge to CK setup time (write cycle) 0.2 0.2 0.2 tCK 1-4 tDSH DQS falling edge hold time from CK (write cycle) 0.2 0.2 0.2 tCK 1-4 tMRD Mode register set command cycle time 14 15 16 ns 1-4 0 0 0 ns 1-4, 7 tCK 1-4, 6 1-4 tWPRES Write preamble setup time tWPST Write postamble 0.40 tWPRE Write preamble 0.25 0.25 0.25 tCK tIH Addr. and control input hold time (fast slew rate) 0.9 0.9 1.2 ns tIS Addr. and control input setup time (fast slew rate) 0.9 0.9 1.2 ns tIH Addr. and control input hold time (slow slew rate) 1.0 1.0 1.2 ns tIS Addr. and control input setup time (slow slew rate) 1.0 1.0 1.2 ns tRPRE Read preamble 0.9 1.1 0.9 1.1 0.9 1.1 tCK 1-4 tRPST Read postamble 0.40 0.60 0.40 0.60 0.40 0.60 tCK 1-4 tRAS Active to Precharge command 45 120,000 45 120,000 50 120,000 ns 1-4 tRC Active to Active/Auto-refresh command period 65 65 70 ns 1-4 tRFC Auto-refresh to Active/Auto-refresh command period 75 75 80 ns 1-4 tRCD Active to Read or Write delay 20 20 20 ns 1-4 Precharge command period 20 20 20 ns 1-4 tRRD Active bank A to Active bank B command 15 15 15 ns 1-4 tWR Write recovery time 15 15 15 ns 1-4 tRP 0.60 0.40 0.60 0.40 0.60 1-4, 12,13 1. Input slew rate >=1V/ns for DDR266 and = 1V/ns for DDR200. 2. The CK/CK input reference level (for timing reference to CK/CK) is the point at which CK and CK cross: the input reference level for signals other than CK/CK, is VREF. CK/CK slew rate are >= 1.0 V/ns. 3. Inputs are not recognized as valid until VREF stabilizes. 4. The Output timing reference level, as measured at the timing reference point indicated in AC Characteristics (Note 3) is VTT. 5. tHZ and tLZ transitions occur in the same access time windows as valid data transitions. These parameters are not referred to a specific voltage level, but specify when the device is no longer driving (HZ), or begins driving (LZ). 6. The maximum limit for this parameter is not a device limit. The device operates with a greater value for this parameter, but system performance (bus turnaround) degrades accordingly. 7. The specific requirement is that DQS be valid (HIGH, LOW, or some point on a valid transition) on or before this CK edge. A valid transition is defined as monotonic and meeting the input slew rate specifications of the device. When no writes were previously in progress on the bus, DQS will be transitioning from Hi-Z to logic LOW. If a previous write was in progress, DQS could be HIGH, LOW, or transitioning from HIGH to LOW at this time, depending on tDQSS. 8. A maximum of eight Autorefresh commands can be posted to any given DDR SDRAM device. 9. QFC is enabled as soon as possible after the rising CK edge that registers the Write command. 10. QFC is disabled as soon as possible after the last valid DQS edge transitions Low. 11. For each of the terms, if not already an integer, round to the next highest integer. tCK is equal to the actual system clock cycle time. 12. These parameters guarantee device timing, but they are not necessarily tested on each device 13. Fast slew rate >= 1 V/ns, slow slew rate >= 0.5V/ns. For input setup & holdtime derating for slew rates less than 0.5 V/ns see JEDEC ballot JC-423-00-210, JCB-00-087, Item 1178.10 Page 57 of 72 3/01 HYB25D256400/800T/AT 256-Mbit Double Data Rate SDRAM Electrical Characteristics & AC Timing for DDR266/DDR200 - Absolute Specifications (0 °C ≤ TA ≤ 70 °C; VDDQ = 2.5V ± 0.2V; VDD = 2.5V ± 0.2V, See AC Characteristics) (Part 3 of 3) Symbol Parameter DDR266A -7 Min Max DDR266B -7.5 Min Max DDR200 -8 Min Unit Notes tCK 1-4,11 Max tDAL Auto precharge write recovery + precharge time tWTR Internal write to read command delay 1 1 1 tCK 1-4 tXSNR Exit self-refresh to non-read command 75 75 80 ns 1-4 tXSRD Exit self-refresh to read command 200 200 200 tCK 1-4 tREFI Average Periodic Refresh Interval 7.8 µs 1-4, 8 tQPRE QFC preamble during reads 0.9 1.1 0.9 1.1 0.9 1.1 tCK 1-,12 tQPST QFC postamble during reads 0.4 0.6 0.4 0.6 0.4 0.6 tCK 1-,12 tQCK QFC output access time form CK/CK, for writes 4.0 ns 1-4, 9, 12 tQOH QFC output hold time for writes 2.0 ns 1-4, 10,12 (twr/tck + (trp/tck) 7.8 7.8 4.0 1.25 2.0 4.0 1.25 2.0 1.25 1. Input slew rate >=1V/ns for DDR266 and = 1V/ns for DDR200. 2. The CK/CK input reference level (for timing reference to CK/CK) is the point at which CK and CK cross: the input reference level for signals other than CK/CK, is VREF. CK/CK slew rate are >= 1.0 V/ns. 3. Inputs are not recognized as valid until VREF stabilizes. 4. The Output timing reference level, as measured at the timing reference point indicated in AC Characteristics (Note 3) is VTT. 5. tHZ and tLZ transitions occur in the same access time windows as valid data transitions. These parameters are not referred to a specific voltage level, but specify when the device is no longer driving (HZ), or begins driving (LZ). 6. The maximum limit for this parameter is not a device limit. The device operates with a greater value for this parameter, but system performance (bus turnaround) degrades accordingly. 7. The specific requirement is that DQS be valid (HIGH, LOW, or some point on a valid transition) on or before this CK edge. A valid transition is defined as monotonic and meeting the input slew rate specifications of the device. When no writes were previously in progress on the bus, DQS will be transitioning from Hi-Z to logic LOW. If a previous write was in progress, DQS could be HIGH, LOW, or transitioning from HIGH to LOW at this time, depending on tDQSS. 8. A maximum of eight Autorefresh commands can be posted to any given DDR SDRAM device. 9. QFC is enabled as soon as possible after the rising CK edge that registers the Write command. 10. QFC is disabled as soon as possible after the last valid DQS edge transitions Low. 11. For each of the terms, if not already an integer, round to the next highest integer. tCK is equal to the actual system clock cycle time. 12. These parameters guarantee device timing, but they are not necessarily tested on each device 13. Fast slew rate >= 1 V/ns, slow slew rate >= 0.5V/ns. For input setup & holdtime derating for slew rates less than 0.5 V/ns see JEDEC ballot JC-423-00-210, JCB-00-087, Item 1178.10 Page 58 of 72 3/01 HYB25D256400/800T/AT 256-Mbit Double Data Rate SDRAM Electrical Characteristics & AC Timing for DDR266B - Applicable Specifications Expressed in Clock Cycles (0 °C ≤ TA ≤ 70 °C; VDDQ = 2.5V ± 0.2V; VDD = 2.5V ± 0.2V, See AC Characteristics) DDR266B @ CL=2.5 Symbol Parameter Units Notes 2 tCK 1-5 0.25 tCK 1-5 tCK 1-5 Min tMRD tWPRE Mode register set command cycle time Write preamble Max tRAS Active to Precharge command 6 tRC Active to Active/Auto-refresh command period 9 tCK 1-5 tRFC Auto-refresh to Active/Auto-refresh command period 10 tCK 1-5 tRCD Active to Read or Write delay 3 tCK 1-5 Precharge command period 3 tCK 1-45 tRRD Active bank A to Active bank B command 2 tCK 1-5 tWR Write recovery time 2 tCK 1-5 tDAL Auto precharge write recovery + precharge time 5 tCK 1-5 tWTR Internal write to read command delay 1 tCK 1-5 tXSNR Exit self-refresh to non-read command 10 tCK 1-5 tXSRD Exit self-refresh to read command 200 tCK 1-5 tRP 16000 1. Input slew rate = 1V/ns 2. The CK/CK input reference level (for timing reference to CK/CK) is the point at which CK and CK cross: the input reference level for signals other than CK/CK, is VREF. 3. Inputs are not recognized as valid until VREF stabilizes. 4. The Output timing reference level, as measured at the timing reference point indicated in AC Characteristics (Note 3) is VTT. 5. tHZ and tLZ transitions occur in the same access time windows as valid data transitions. These parameters are not referred to a specific voltage level, but specify when the device is no longer driving (HZ), or begins driving (LZ). Page 59 of 72 3/01 HYB25D256400/800T/AT 256-Mbit Double Data Rate SDRAM Data Input (Write) (Timing Burst Length = 4) tDQSL tDQSH DQS tDH tDS DI n DQ tDH tDS DM DI n = Data In for column n. 3 subsequent elements of data in are applied in programmed order following DI n. Data Output (Read) Don’t Care (Timing Burst Length = 4) DQS tDQSQ max tQH DQ tQH (Data output hold time from DQS) tDQSQ and tQH are only shown once and are shown referenced to different edges of DQS, only for clarify of illustration. t.DQSQ and tQH both apply to each of the four relevant edges of DQS. tDQSQ max. is used to determine the worst case setup time for controller data capture. tQH is used to determine the worst case hold time for controller data capture. Page 60 of 72 3/01 Initialize and Mode Register Sets Page 61 of 72 VDD * VTT is not applied directly to the device, however tVTD must be greater than or equal to zero to avoid device latchup. VDDQ ** tMRD is required before any command can be applied and 200 cycles of CK are required before a Read command can be applied. tVTD The two Autorefresh commands may be moved to follow the first MRS, but precede the second Precharge All command. VTT (System*) VREF tCK 200µs CK 200 cycles of CK** tCH tMRD tCL tMRD tRP tRFC tRFC tMRD CK tIH CKE LVCMOS LOW LEVEL tIS tIH tIS Command NOP PRE EMRS MRS PRE AR AR ACT CODE RA CODE RA BA DM tIH tIS A0-A9, A11 CODE tIH tIS CODE tIH tIH tIS A10 tIS CODE CODE ALL BANKS ALL BANKS tIH tIS BA0, BA1 High-Z BA0=H BA0=L BA0=L BA1=L BA1=L BA1=L DQS High-Z DQ 3/01 Don’t Care Power-up: VDD and CK stable Extended Mode Register Set Load Mode Register, Reset DLL Load Mode Register (with A8 = L) HYB25D256400/800T/AT 256-Mbit Double Data Rate SDRAM MRS tCH Power Down Mode Page 62 of 72 tCK CK tCL CK tIH tIS tIS tIS CKE tIH tIS Command VALID* NOP NOP VALID tIH tIS ADDR VALID VALID DQ DM Enter Power Down Mode No column accesses are allowed to be in progress at the time power down is entered. * = If this command is a Precharge (or if the device is already in the idle state) then the power down mode shown is Precharge power down. If this command is an Active (or if at least one row is already active), then the power down mode shown is Active power down. Exit Power Down Mode Don’t Care HYB25D256400/800T/AT 256-Mbit Double Data Rate SDRAM DQS 3/01 Auto Refresh Mode Page 63 of 72 tRP tCH tCL tCK tRFC CK CK tRFC tIH tIS CKE VALID VALID tIH tIS Command NOP PRE NOP NOP AR NOP A0-A8 AR NOP NOP ACT RA RA A9, A11,A12 ALL BANKS RA ONE BANK tIH tIS BA0, BA1 BANK(S) BA DQS DQ DM PRE = Precharge; ACT = Active; RA = Row address; BA = Bank address; AR = Autorefresh. NOP commands are shown for ease of illustration; other valid commands may be possible at these times. DM, DQ, and DQS signals are all don’t care/high-Z for operations shown. Don’t Care HYB25D256400/800T/AT 256-Mbit Double Data Rate SDRAM A10 3/01 tRP* tCK tCH CK CK 200 cycles tCL Self Refresh Mode Page 64 of 72 Clock must be stable before exiting Self Refresh Mode tIH tIS tIS tIS CKE tIH tXSRD, tXSRN tIS Command NOP AR NOP VALID tIH tIS VALID ADDR DQ DM Enter Self Refresh Mode * = Device must be in the all banks idle state before entering Self Refresh Mode. ** = tXSNR is required before any non-read command can be applied, and tXSRD (200 cycles of CK). are required before a Read command can be applied. Exit Self Refresh Mode Don’t Care HYB25D256400/800T/AT 256-Mbit Double Data Rate SDRAM DQS 3/01 tCH tRP tIH tIS tIH CKE VALID VALID VALID NOP NOP NOP tIH tIS Command NOP Read NOP PRE NOP NOP ACT tIH tIS A0-A9, A11, A12 COL n RA tIH tIS ALL BANKS RA A10 BA0, BA1 DIS AP tIH tIS ONE BANK BA x BA x* BA x DM DQS Case 1: tAC/t DQSCK = min tAC (min) tHZ (min) tRPST tDQSCK (min) CL=2 DQ DO n tLZ (max) tRPRE DQS Case 2: tAC/tDQSCK = max tHZ (max) tRPST tAC (max) tLZ (max) tDQSCK (max) DQ DO n DO n = data out from column n. 3 subsequent elements of data out are provided in the programmed order following DO n. 3/01 DIS AP = Disable Auto Precharge. * = Don’t care if A10 is High at this point. PRE = Precharge; ACT = Active; RA = Row address; BA = Bank address. NOP commands are shown for ease of illustration; other commands may be valid at these times. Don’t Care HYB25D256400/800T/AT 256-Mbit Double Data Rate SDRAM tLZ (min) tRPRE Read without Auto Precharge (Burst Length = 4) Page 65 of 72 tCL tCK CK CK tRP tCH CK CK tIH tIH tIS CKE VALID VALID VALID NOP NOP NOP tIH tIS Command NOP Read NOP NOP NOP NOP ACT tIH tIS A0-A9, A11, A12 COL n RA tIH tIS A10 RA EN AP tIH tIS BA0, BA1 BA x BA x DM DQS tHZ (min) Case 1: tAC/tDQSCK = min tAC (min) CL=2 tRPST tHZ (min) tDQSCK (min) DQ DO n tLZ (max) tRPRE DQS Case 2: tAC/tDQSCK = max tAC (max) tLZ (max) tHZ (max) tRPST tDQSCK (max) DQ DO n DO n = data out from column n. 3 subsequent elements of data out are provided in the programmed order following DO n. EN AP = enable Auto Precharge. ACT = active; RA = row address. NOP commands are shown for ease of illustration; other commands may be valid at these times. Don’t Care HYB25D256400/800T/AT 256-Mbit Double Data Rate SDRAM tLZ (min) tRPRE Read with Auto Precharge (Burst Length = 4) Page 66 of 72 tCL tCK 3/01 tCH CK CK tRC tIH tIS VALID CKE tIH tIS Command NOP ACT NOP Read NOP PRE NOP NOP ACT NOP tIH tIS A0-A9, A11, A12 RA RA COL n tIH tIS A10 ALL BANKS RA RA DIS AP ONE BANK BA x BA x* tIH tIS BA0, BA1 BA x Bank Read Access (Burst Length = 4) Page 67 of 72 tCL tCK BA x DM tRP DQS tRCD Case 1: tAC/t DQSCK = min tLZ (min) tRAS tHZ (min) tAC (min) CL=2 tRPST tDQSCK (min) DQ DO n tLZ (max) tRPRE DQS tHZ (max) Case 2: tAC/tDQSCK = max tAC (max) tLZ (max) tRPST tDQSCK (max) DQ DO n = data out from column n. 3 subsequent elements of data out are provided in the programmed order following DO n. DIS AP = disable Auto Precharge. * = Don’t care if A10 is High at this point. PRE = Precharge; ACT = Active; RA = Row address; BA = Bank address. NOP commands are shown for ease of illustration; other commands may be valid at these times. DO n Don’t Care HYB25D256400/800T/AT 256-Mbit Double Data Rate SDRAM tLZ (min) tRPRE 3/01 tWR tCL tRP CK CK tIH tIS tIH VALID CKE tIH tIS Command NOP Write NOP NOP NOP NOP PRE NOP NOP ACT tIH tIS A0-A9, A11, A12 COL n RA tIH ALL BANKS tIS A10 DIS AP RA ONE BANK tIH BA0, BA1 BA x BA x* tDSH tWPRE tWPRES BA tDQSH tDQSL tDQSS tWPST DQS DQ DIn DM 3/01 tDQSS = min. DIn = Data in for column n. 3 subsequent elements of data in are applied in the programmed order following DIn. DIS AP = Disable Auto Precharge. * = Don’t care if A10 is High at this point. PRE = Precharge; ACT = Active; RA = Row address; BA = Bank address. NOP commands are shown for ease of illustration; other valid commands may be possible at these times. Don’t Care HYB25D256400/800T/AT 256-Mbit Double Data Rate SDRAM tIS Write without Auto Precharge (Burst Length = 4) Page 68 of 72 tCH tCK tWR tCL CK tRP CK tIH tDAL tIS CKE VALID VALID VALID NOP NOP NOP tIH tIS NOP Command Write NOP NOP NOP NOP ACT tIH tIS A0-A9, A11, A12 COL n RA tIH tIS EN AP A10 RA tIH BA0, BA1 BA x BA tWPRES tDSH tDQSH tDQSS tDQSL tWPST DQS DIn DQ DM tWPRE tDQSS = min. 3/01 DIn = Data in for column n. 3 subsequent elements of data in are applied in the programmed order following DIn. EN AP = Enable Auto Precharge. ACT = Active; RA = Row address; BA = Bank address. NOP commands are shown for ease of illustration; other valid commands may be possible at these times. Don’t Care HYB25D256400/800T/AT 256-Mbit Double Data Rate SDRAM tIS Write with Auto Precharge (Burst Length = 4) Page 69 of 72 tCH tCK tCL CK CK tIH tIS VALID CKE tIH tRAS tIS Command NOP ACT NOP Write NOP NOP NOP NOP PRE NOP tIH tIS A0-A9, A11, A12 RA Col n tIH tIS A10 Bank Write Access (Burst Length = 4) Page 70 of 72 tCH tCK ALL BANKS DIS AP RA ONE BANK tIH BA x BA x BA x tRCD tDSH tWPRES tWR tDQSH tDQSL tDQSS tWPST DQS DQ DIn DM tWPRE tDQSS = min. DI n = data in for column n. 3 subsequent elements of data in are applied in the programmed order following DI n. DIS AP = Disable Auto Precharge. * = don’t care if A10 is High at this point. PRE = Precharge; ACT = Active; RA = Row address. NOP commands are shown for ease of illustration; other valid commands may be possible at these times. Don’t Care HYB25D256400/800T/AT 256-Mbit Double Data Rate SDRAM tIS BA0, BA1 3/01 tCL CK CK tIH tIS CKE VALID tIH tIS Command NOP Write NOP NOP NOP NOP PRE NOP NOP ACT tIH tIS A0-A9, A11, A12 COL n RA tIH tIS A10 ALL BANKS DIS AP Write DM Operation (Burst Length = 4) Page 71 of 72 tCH tCK RA ONE BANK tIH BA0, BA1 BA x BA x* tWR tWPRES tRP tDSH tDQSH tDQSL tDQSS BA tWPST DQS DQ DIn DM 3/01 DI n = data in for column n. 3 subsequent elements of data in are applied in the programmed order following DI n (the second element of the 4 is masked). DIS AP = Disable Auto Precharge. * = Don’t care if A10 is High at this point. PRE = Precharge; ACT = Active; RA = Row address; BA = Bank address. NOP commands are shown for ease of illustration; other valid commands may be possible at these times. tDQSS = min. Don’t Care HYB25D256400/800T/AT 256-Mbit Double Data Rate SDRAM tIS HYB25D256400/800T/AT 256-Mbit Double Data Rate SDRAM Package Dimensions (400mil; 66 lead; Thin Small Outline Package) Gage Plane 0,65 Basic _ 0,05 0,35 +0,1 Lead #1 Page 72 of 72 22,22±0,13 0,805 REF 0.1 Seating Plane 10,16±0,13 0,25 Basic 1,20 max 0,05 min Plastic Package, P-TSOPII-66 (400mil; 66 lead) Thin Small Outline Package 0,5±0,1 11,76±0,2 GPX09261 3/01 Attention please ! As far as patents or other rights of third parties are concerned, liability is only assumed for components, not for applications, processes and circuits implemented within components or assemblies. This infomation describes the type of components and shall not be considered as assured characteristics. Terms of delivery and rights to change design reserved. For questions on technology, delivery and prices please contact INFINEON Technologies Offices in Munich or the INFINEON Technologies Sales Offices and Representatives worldwide. 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