FEBRUARY 2011 AS4C16M16S 256Mb / 16M x 16 bit Synchronous DRAM (SDRAM) Alliance Memory Features * * * * * * * * * * * * Table 1. Key Specifications AS4C16M16S tCK3 Clock Cycle time (min.) tAC3 Access time from CLK (max.) tRAS Row Active time (min.) tRC Row Cycle time (min.) Fast access time from clock: 4.5/5.4/5.4 ns Fast clock rate: 200/166/143 MHz Fully synchronous operation Internal pipelined architecture 4M word x 16-bit x 4-bank Programmable Mode registers - CAS Latency: 2, or 3 - Burst Length: 1, 2, 4, 8, or full page - Burst Type: interleaved or linear burst - Burst stop function Auto Refresh and Self Refresh 8192 refresh cycles/64ms CKE power down mode Single +3.3V power supply Interface: LVTTL 54-pin 400 mil plastic TSOP II package - Pb free and Halogen free Table 2. Ordering Information Part Number Frequency AS4C16M16S-5TCN 200 MHz AS4C16M16S-6TCN 166 MHz AS4C16M16S-6TIN 166 MHz AS4C16M16S-7TCN 143 MHz T : indicates TSOP II package N : indicates Pb free and Halogen free Overview The AS4C16M16S SDRAM is a high-speed CMOS synchronous DRAM containing 256 Mbits. It is internally configured as 4 Banks of 4M word x 16 DRAM with a synchronous interface (all signals are registered on the positive edge of the clock signal, CLK). Read and write accesses to the SDRAM are burst oriented; accesses start at selected location and continue for a programmed number of locations in a programmed sequence. Accesses begin with the registration of a BankActivate command which is then followed by a Read or Write command. The AS4C16M16S provides for programmable Read or Write burst length of 1, 2, 4, 8, or full page, with a burst termination option. An auto precharge function may be enabled to provide a self-timed row precharge that is initiated at the end of the burst sequence. The refresh functions, either Auto or Self Refresh are easy to use. By having a programmable mode register, the system can choose the most suitable modes to maximize its performance. These devices are well suited for application requiring high memory bandwidth and particularly well suited to high performance PC applications. 1 -5/6/7 5/6/7 ns 4.5/5.4/5.4 ns 40/42/49 ns 55/60/63 ns Package TSOP II TSOP II TSOP II TSOP II FEBRUARY 2011 AS4C16M16S 256Mb / 16M x 16 bit Synchronous DRAM (SDRAM) 2 FEBRUARY 2011 AS4C16M16S 256Mb / 16M x 16 bit Synchronous DRAM (SDRAM) Pin Descriptions Table 3. Pin Details of AS4C16M16S Symbol Type Description CLK Input Clock: CLK is driven by the system clock. All SDRAM input signals are sampled on the positive edge of CLK. CLK also increments the internal burst counter and controls the output registers. CKE Input Clock Enable: CKE activates (HIGH) and deactivates (LOW) the CLK signal. If CKE goes low synchronously with clock (set-up and hold time same as other inputs), the internal clock is suspended from the next clock cycle and the state of output and burst address is frozen as long as the CKE remains low. When all banks are in the idle state, deactivating t he clock controls the entry to the Power Down and Self Refresh modes. CKE is synchronous except after the device enters Power Down and Self Refresh modes, where CKE becomes asynchronous until exiting the same mode. The input buffers, including CLK, are disabled during Power Down and Self Refresh modes, providing low standby power. BA0,BA1 Input Bank Activate: BA0, BA1 input select the bank for operation. BA1 BA0 Select Bank 0 0 BANK #A 0 1 BANK #B 1 0 BANK #C 1 1 BANK #D A0-A12 Input Address Inputs: A0-A12 are sampled during the BankActivate command (row address A0A12) and Read/Write command (column address A0-A8 with A10 defining Auto Precharge) to select one location out of the 4M available in the respective bank. During a Precharge command, A10 is sampled to determine if all banks are to be precharged (A10 = HIGH). The address inputs also provide the op-code during a Mode Register Set command. CS# Input Chip Select: CS# enables (sampled LOW) and disables (sampled HIGH) the command decoder. All commands are masked when CS# is sampled HIGH. CS# provides for external bank selection on systems with multiple banks. It is considered part of the command code. RAS# Input Row Address Strobe: The RAS# signal defines the operation commands in conjunction with the CAS# and WE# signals and is latched at the positive edges of CLK. When RAS# and CS# are asserted "LOW" and CAS# is asserted "HIGH," either the BankActivate command or t he Precharge command is selected by the WE# signal. When the WE# is asserted "HIGH," the BankActivate command is selected and the bank designated by BA is turned on to the active state. When the WE# is asserted "LOW," the Precharge command is selected and the bank designated by BA is switched to the idle state after the precharge operation. CAS# Input Column Address Strobe: The CAS# signal defines the operation commands in conjunction with the RAS# and WE# signals and is latched at the positive edges of CLK. When RAS# is held "HIGH" and CS# is asserted "LOW," the column access is started by asserting CAS# "LOW." Then, the Read or Write command is selected by asserting WE# "LOW" or "HIGH." WE# Input Write Enable: The WE# signal defines the operation commands in conjunction with the RAS# and CAS# signals and is latched at the positive edges of CLK. The WE# input is used to select the Bank Activate or Precharge command and Read or Write command. 3 FEBRUARY 2011 AS4C16M16S 256Mb / 16M x 16 bit Synchronous DRAM (SDRAM) LDQM, UDQM DQ0-DQ15 Input Input data in write mode. Input / Output NC/RFU VDDQ Data Input/Output Mask: Controls output buffers in read mode and masks Data I/O: The DQ0-15 input and output data are synchronized with the positive edges of CLK. The I/Os are maskable during Reads and Writes. No Connect: These pins should be left unconnected. Supply DQ Power: Provide isolated power to DQs for improved noise immunity. ( 3.3V 0.3V ) VSSQ Supply DQ Ground: Provide isolated ground to DQs for improved noise immunity. (0V) VDD Supply Power Supply: +3.3V 0.3V VSS Supply Ground 4 FEBRUARY 2011 AS4C16M16S 256Mb / 16M x 16 bit Synchronous DRAM (SDRAM) Operation Mode Fully synchronous operations are performed to latch the commands at the positive edges of CLK. Table 4 shows the truth table for the operation commands. Table 4. Truth Table (Note (1), (2)) CKEn-1 CKEn DQM BA0,1 A10 A0-9,12 CS# RAS# CAS# WE# Command State BankActivate Idle(3) H X X V BankPrecharge Any H X X V L PrechargeAll Any H X X X Write Active(3) H X V Write and AutoPrecharge Active(3) H X V Read Active(3) H X V V L Read and Autoprecharge Active(3) H X V V H Mode Register Set Idle H X X No-Operation Any H X X X X Active(4) H X X X Device Deselect Any H X X AutoRefresh Idle H H SelfRefresh Entry Idle H Idle L Burst Stop SelfRefresh Exit Row address L L H X L L HL H X L L HL V L L H L L V H Column address (A0 ~ A8) L H L L L H LH L H LH L L LL X L H HH X X L H H X X X H X XX X X X X L L L H L X X X X L L L H H X X X X H X XX L H HH H X XX L V VV H X XX L H HH Column address (A0 ~ A8) OP code (SelfRefresh) Clock Suspend Mode Entry Power Down Mode Entry Clock Suspend Mode Exit Power Down Mode Exit Active Any(5) H H L L X X X X X X X X L Active L H X X X X X X XX Any L H X X X X H X XX L H HH X X X X X X (PowerDown) Data Write/Output Enable H Active H X L Data Mask/Output Disable X X X Active H X H X X X X X Note: 1. V=Valid, X=Don't Care L=Low level H=High level 2. CKEn signal is input level when commands are provided. CKEn-1 signal is input level one clock cycle before the commands are provided. 3. These are states of bank designated by BA signal. 4. Device state is 1, 2, 4, 8, and full page burst operation. 5. Power Down Mode cannot enter in the burst operation. When this command is asserted in the burst cycle, device state is clock suspend mode. 5 FEBRUARY 2011 AS4C16M16S 256Mb / 16M x 16 bit Synchronous DRAM (SDRAM) Commands 1 BankActivate (RAS# = "L", CAS# = "H", WE# = "H", BAs = Bank, A0-A12 = Row Address) The BankActivate command activates the idle bank designated by the BA0, 1 signal. By latching the row address on A0 to A12 at the time of this command, the selected row access is initiated. The read or write operation in the same bank can occur after a time delay of tRCD (min.) from the time of bank activation. A subsequent BankActivate command to a different row in the same bank can only be issued after the previous active row has been precharged (refer to the following figure). The minimum time interval between successive BankActivate commands to the same bank is defined by tRC (min.). The SDRAM has four internal banks on the same chip and shares part of the internal circuitry to reduce chip area; therefore it restricts the back-toback activation of the two banks. t RRD (min.) specifies the minimum time required between activating different banks. After this command is used, the Write command and the Block Write command perform the no mask write operation. 2 BankPrecharge command (RAS# = "L", CAS# = "H", WE# = "L", BAs = Bank, A10 = "L", A0-A9, A11 and A12 = Don't care) The BankPrecharge command precharges the bank designated by BA signal. The precharged bank is switched from the active state to the idle state. This command can be asserted anytime after tRAS(min.) is satisfied from the BankActivate command in the desired bank. The maximum time any bank can be active is specified by t RAS(max.). Therefore, the precharge function must be performed in any active bank within t RAS(max.). At the end of precharge, the precharged bank is still in the idle state and is ready to be activated again. 3 PrechargeAll command (RAS# = "L", CAS# = "H", WE# = "L", BAs = Dont care, A10 = "H", A0-A9, A11 and A12 = Don't care) The PrechargeAll command precharges all banks simultaneously and can be issued even if all banks are not in the active state. All banks are then switched to the idle state. 4 Read command (RAS# = "H", CAS# = "L", WE# = "H", BAs = Bank, A10 = "L", A0-A8 = Column Address) The Read command is used to read a burst of data on consecutive clock cycles from an active row in an active bank. The bank must be active for at least tRCD (min.) before the Read command is issued. During read bursts, the valid data-out element from the starting column address will be available following the CAS# latency after the issue of the Read command. Each subsequent data-out element will be valid by the next positive clock edge (refer to the following figure). The DQs go into high-impedance at the end of the burst unless other command is initiated. The burst length, burst sequence, and CAS# latency are determined by the mode register, which is already programmed. A full-page burst will continue until terminated (at the end of the page it will wrap to column 0 and continue). 6 FEBRUARY 2011 AS4C16M16S 256Mb / 16M x 16 bit Synchronous DRAM (SDRAM) The read data appears on the DQs subject to the values on the DQM inputs two clocks earlier (i.e. DQM latency is two clocks for output buffers). A read burst without the auto precharge function may be interrupted by a subsequent Read or Write command to the same bank or the other active bank before the end of the burst length. It may be interrupted by a BankPrecharge/PrechargeAll command to the same bank too. The interrupt coming from the Read command can occur on any clock cycle following a previous Read command (refer to the following figure). The DQM inputs are used to avoid I/O contention on the DQ pins when the interrupt comes from a Write command. The DQMs must be asserted (HIGH) at least two clocks prior to the Write command to suppress data-out on the DQ pins. To guarantee the DQ pins against I/O contention, a single cycle with high-impedance on the DQ pins must occur between the last read data and the Write command (refer to the following three figures). If the data output of the burst read occurs at the second clock of the burst write, the DQMs must be asserted (HIGH) at least one clock prior to the Write command to avoid internal bus contention. 7 FEBRUARY 2011 AS4C16M16S 256Mb / 16M x 16 bit Synchronous DRAM (SDRAM) A read burst without the auto precharge function may be interrupted by a BankPrecharge/PrechargeAll command to the same bank. The following figure shows the optimum time that BankPrecharge/PrechargeAll command is issued in different CAS# latency. 8 FEBRUARY 2011 AS4C16M16S 256Mb / 16M x 16 bit Synchronous DRAM (SDRAM) 5 Read and AutoPrecharge command (RAS# = "H", CAS# = "L", WE# = "H", BAs = Bank, A10 = "H", A0-A8 = Column Address) The Read and AutoPrecharge command automatically performs the precharge operation after the read operation. Once this command is given any subsequent command cannot occur within a time delay of {t RP (min.) + burst length}. At full-page burst, only the read operation is performed in this command and the auto precharge function is ignored. 6 Write command (RAS# = "H", CAS# = "L", WE# = "L", BAs = Bank, A10 = "L", A0-A8 = Column Address) The Write command is used to write a burst of data on consecutive clock cycles from an active row in an active bank. The bank must be active for at least tRCD (min.) before the Write command is issued. During write bursts, the first valid data-in element will be registered coincident with the Write command. Subsequent data elements will be registered on each successive positive clock edge (refer to the following figure). The DQs remain with high-impedance at the end of the burst unless another command is initiated. The burst length and burst sequence are determined by the mode register, which is already programmed. A full-page burst will continue until terminated (at the end of the page it will wrap to column 0 and continue). A write burst without the auto precharge function may be interrupted by a subsequent Write, BankPrecharge/PrechargeAll, or Read command before the end of the burst length. An interrupt coming from Write command can occur on any clock following the previous Write command (refer to the following figure). 9 FEBRUARY 2011 AS4C16M16S 256Mb / 16M x 16 bit Synchronous DRAM (SDRAM) The Read command that interrupts a write burst without auto precharge function should be issued one cycle after the clock edge in which the last data-in element is registered. In order to avoid data contention, input data must be removed from the DQs at least one clock cycle before the first read data appears on the outputs (refer to the following figure). Once the Read command is registered, the data inputs will be ignored and writes will not be executed. The BankPrecharge/PrechargeAll command that interrupts a write burst without the auto precharge function should be issued m cycles after the clock edge in which the last data-in element is registered, where m equals tWR/tCK rounded up to the next whole number. In addition, the DQM signals must be used to mask input data, starting with the clock edge following the last data-in element and ending with the clock edge on which the BankPrecharge/PrechargeAll command is entered (refer to the following figure). 10 FEBRUARY 2011 AS4C16M16S 256Mb / 16M x 16 bit Synchronous DRAM (SDRAM) 7 Write and AutoPrecharge command (RAS# = "H", CAS# = "L", WE# = "L", BAs = Bank, A10 = "H", A0-A8 = Column Address) The Write and AutoPrecharge command performs the precharge operation automatically after the write operation. Once this command is given, any subsequent command cannot occur within a time delay of {(burst length - 1) + tWR + tRP (min.)}. At full-page burst, only the write operation is performed in this command and the auto precharge function is ignored. 8 Mode Register Set command (RSAS# = "L", CAS# = "L", WE# = "L", A0-A12 = Register Data) The mode register stores the data for controlling the various operating modes of SDRAM. The Mode Register Set command programs the values of CAS# latency. Addressing Mode and Burst Length in the Mode register to make SDRAM useful for a variety of different applications. The default values of the Mode Register after power-up are undefined; therefore this command must be issued at the power-up sequence. The state of pins A0 ~ A12 in the same cycle is the data written to the mode register. Two clock cycles are required to complete the write in the mode register (refer to the following figure). The contents of the mode register can be changed using the same command and the clock cycle requirements during operation as long as all banks are in the idle state. 11 FEBRUARY 2011 AS4C16M16S 256Mb / 16M x 16 bit Synchronous DRAM (SDRAM) 12 FEBRUARY 2011 AS4C16M16S 256Mb / 16M x 16 bit Synchronous DRAM (SDRAM) * Burst Length Field (A2~A0) This field specifies the data length of column access using the A2~A0 pins and selects the Burst Length to be 2, 4, 8, or full page. Table 6. Burst Length Field A2 A1 A0 Burst Length 0 00 1 0 01 2 0 10 4 0 11 8 1 00 Reserved 1 01 Reserved 1 10 Reserved 1 11 Full Page Length: 512 Full Page * Burst Type Field (A3) The Burst Type can be one of two modes, Interleave Mode or Sequential Mode. Table 7. Burst Type Field * A3 Burst Type 0 Sequential 1 Interleave Burst Definition, Addressing Sequence of Sequential and Interleave Mode Table 8. Burst Definition Burst Length 2 4 8 Full page Start Address A2 A1 A0 X X 0 X X 1 X 0 0 X 0 1 X 1 0 X 1 1 0 0 0 0 0 1 0 1 0 0 1 1 1 0 0 1 0 1 1 1 0 1 1 1 location = 0-511 Sequential Interleave 0, 1 1, 0 0, 1, 2, 3 1, 2, 3, 0 2, 3, 0, 1 3, 0, 1, 2 0, 1, 2, 3, 4, 5, 6, 7 1, 2, 3, 4, 5, 6, 7, 0 2, 3, 4, 5, 6, 7, 0, 1 3, 4, 5, 6, 7, 0, 1, 2 4, 5, 6, 7, 0, 1, 2, 3 5, 6, 7, 0, 1, 2, 3, 4 6, 7, 0, 1, 2, 3, 4, 5 7, 0, 1, 2, 3, 4, 5, 6 n, n+1, n+2, n+3, ...511, 0, 1, 2, ... n-1, n, ... 13 0, 1 1, 0 0, 1, 2, 3 1, 0, 3, 2 2, 3, 0, 1 3, 2, 1, 0 0, 1, 2, 3, 4, 5, 6, 7 1, 0, 3, 2, 5, 4, 7, 6 2, 3, 0, 1, 6, 7, 4, 5 3, 2, 1, 0, 7, 6, 5, 4 4, 5, 6, 7, 0, 1, 2, 3 5, 4, 7, 6, 1, 0, 3, 2 6, 7, 4, 5, 2, 3, 0, 1 7, 6, 5, 4, 3, 2, 1, 0 Not Support FEBRUARY 2011 AS4C16M16S 256Mb / 16M x 16 bit Synchronous DRAM (SDRAM) * CAS# Latency Field (A6~A4) This field specifies the number of clock cycles fr om the assertion of the Read command to the first read data. The minimum whole value of CAS# Latency depends on the frequency of CLK. The minimum whole value satisfying the following formula must be programmed into this field. tCAC(min) CAS# Latency X tCK Table 9. CAS# Latency Field A6 A5 A4 CAS# Latency 0 0 0 Reserved 0 0 1 Reserved 0 1 0 2 clocks 0 1 1 3 clocks 1 X X Reserved Test Mode Field (A8~A7) * These two bits are used to enter the test mode and must be programmed to "00" in normal operation. Table 10. Test Mode Field A8 A7 Test Mode 0 0 normal mode 0 1 Vendor Use Only 1 X Vendor Use Only Write Burst Length (A9) This bit is used to select the write burst mode. When the A9 bit is "0", the Burst-Read-Burst-Write mode is selected. When the A9 bit is "1", the Burst-Read-Single-Write mode is selected. Table 11. Write Burst Length A9 Write Burst Mode 0 Burst-Read-Burst-Write 1 Burst-Read-Single-Write Note: A10 and BA should stay "L" during mode set cycle. 9 No-Operation command (RAS# = "H", CAS# = "H", WE# = "H") The No-Operation command is used to perform a NOP to the SDRAM which is selected (CS# is Low). This prevents unwanted commands from being registered during idle or wait states. 10 Burst Stop command (RAS# = "H", CAS# = "H", WE# = "L") The Burst Stop command is used to terminate either fixed-length or full-page bursts. This command is only effective in a read/write burst without the auto precharge function. The terminated read burst ends after a delay equal to the CAS# latency (refer to the following figure). The termination of a write burst is shown in the following figure. 14 FEBRUARY 2011 AS4C16M16S 256Mb / 16M x 16 bit Synchronous DRAM (SDRAM) 11 Device Deselect command (CS# = "H") The Device Deselect command disables the command decoder so that the RAS#, CAS#, WE# and Address inputs are ignored, regardless of whether the CLK is enabled. This command is similar to the No Operation command. 12 AutoRefresh command (RAS# = "L", CAS# = "L", WE# = "H", CKE = "H", A11 = "Dont care, A0-A12 = Don't care) The AutoRefresh command is used during normal operation of the SDRAM and is analogous to CAS#before-RAS# (CBR) Refresh in conventional DRAMs. This command is non-persistent, so it must be issued each time a refresh is required. The addressing is generated by the internal refresh controller. This makes the address bits a "don't care" during an AutoRefresh command. The internal refresh counter increments automatic ally on every auto refresh cycle to all of the rows. The refresh operation must be performed 4096 times within 64ms. The time required to complete the auto refresh operation is specified by tRC(min.). To provide the AutoRefresh command, all banks need to be in the idle state and the device must not be in power down mode (CKE is high in the previous cycle). This command must be followed by NOPs until the auto refresh operation is completed. The precharge time requirement, tRP(min), must be met before successive auto refresh operations are performed. 13 SelfRefresh Entry command (RAS# = "L", CAS# = "L", WE# = "H", CKE = "L", A0-A12 = Don't care) The SelfRefresh is another refresh mode available in the SDRAM. It is the preferred refresh mode for data retention and low power operation. Once the SelfRefresh command is registered, all the inputs to the SDRAM become "don't care" with t he exception of CKE, which must remain LOW. The refresh addressing and timing is internally generated to reduce power consumption. The SDRAM may remain in SelfRefresh mode for an indefinite period. The SelfRefresh mode is exited by restarting the external clock and then asserting HIGH on CKE (SelfRefresh Exit command). 15 FEBRUARY 2011 AS4C16M16S 256Mb / 16M x 16 bit Synchronous DRAM (SDRAM) 14 SelfRefresh Exit command This command is used to exit from the SelfRefresh mode. Once this command is registered, NOP or Device Deselect commands must be issued for t XSR(min.) because time is required for the completion of any bank currently being internally refreshed. If auto refresh cycles in bursts are performed during normal operation, a burst of 4096 auto refresh cycles should be completed just prior to entering and just after exiting the SelfRefresh mode. 15 Clock Suspend Mode Entry / PowerDown Mode Entry command (CKE = "L") When the SDRAM is operating the burst cycle, the internal CLK is suspended (masked) from the subsequent cycle by issuing this command (asse rting CKE "LOW"). The device operation is held intact while CLK is suspended. On the other hand, when all banks are in the idle state, this command performs entry into the PowerDown mode. All input and output buffers (except the CKE buffer) are turned off in the PowerDown mode. The device may not remain in the Clock Suspend or PowerDown state longer than the refresh period (64ms) since the command does not perform any refresh operations. 16 Clock Suspend Mode Exit / PowerDown Mode Exit command (CKE= "H") When the internal CLK has been suspended, the operation of the internal CLK is reinitiated from the subsequent cycle by providing this command (asserting CKE "HIGH", the command should be NOP or deselect). When the device is in the PowerDown mode, the device exits this mode and all disabled buffers are turned on to the active state. tPDE(min.) is required when the device exits from the PowerDown mode. Any subsequent commands can be issued after one clock cycle from the end of this command. 17 Data Write / Output Enable, Data Mask / Output Disable command (DQM = "L", "H") During a write cycle, the DQM signal functions as a Data Mask and can control every word of the input data. During a read cycle, the DQM functions as the controller of output buffers. DQM is also used for device selection, byte selection and bus control in a memory system. 16 FEBRUARY 2011 AS4C16M16S 256Mb / 16M x 16 bit Synchronous DRAM (SDRAM) Table 12. Absolute Maximum Rating Symbol Item Rating Unit Note V 1 VIN, VOUT Input, Output Voltage - 0.5 ~ 4.6 VDD, VDDQ Power Supply Voltage -0.5 ~ 4.6 V 1 TA Ambient Temperature 0 ~ 70 C 1 TSTG Storage Temperature - 65 ~ 150 C 1 TSOLDER Soldering Temperature (10 second) 260 C 1 PD Power Dissipation 1 W 1 IOUT Short Circuit Output Current 50 mA 1 Table 13. Recommended D.C. Operating Conditions (TA = 0~70C) Symbol Parameter Min. Typ. VDD Power Supply Voltage 3.0 3.3 VDDQ Power Supply Voltage(for I/O Buffer) 3.0 Max. Unit Note 3.6 V 2 3.3 3.6 V 2 VIH LVTTL Input High Voltage 2.0 3.0 VDDQ +0.3 V 2 VIL LVTTL Input Low Voltage - 0.3 0 0.8 V 2 IIL Input Leakage Current ( 0V VIN VDD, All other pins not under test = 0V ) - 10 10 A IOL Output Leakage Current Output disable, 0V VOUT VDDQ) - 10 10 A VOH LVTTL Output "H" Level Voltage ( IOUT = -2mA ) 2.4 V VOL LVTTL Output "L" Level Voltage ( IOUT = 2mA ) 0.4 V Table 14. Capacitance (VDD = 3.3V, f = 1MHz, TA = 25C) Symbol Parameter Min. CI Input Capacitance 2.5 5 pF 4 6.5 pF CI/O Input/Output Capacitance Note: These parameters are periodically sampled and are not 100% tested. 17 Max. Unit FEBRUARY 2011 AS4C16M16S 256Mb / 16M x 16 bit Synchronous DRAM (SDRAM) Table 15. D.C. Characteristics (VDD = 3.3V 0.3V, TA = 0~70C) Description/Test condition Operating Current tRC tRC(min), Outputs Open One bank active Precharge Standby Current in non-power down mode tCK = 15ns, CS# VIH(min), CKE VIH Input signals are changed every 2clks Precharge Standby Current in non-power down mode tCK = , CLK VIL(max), CKE VIH Precharge Standby Current in power down mode tCK = 15ns, CKE VIL(max) Precharge Standby Current in power down mode tCK = , CKE VIL(max) Active Standby Current in non-power down mode tCK = 15ns, CKE VIH(min), CS# VIH(min) Input signals are changed every 2clks Active Standby Current in non-power down mode CKE VIH(min), CLK VIL(max), tCK = Operating Current (Burst mode) tCK =tCK(min), Outputs Open, Multi-bank interleave Refresh Current tRC tRC(min) Self Refresh Current CKE 0.2V ; for other inputs VIHVDD - 0.2V, VIL 0.2V 18 Symbol -5 -6 Max. -7 IDD1 110 100 100 IDD2N 45 40 40 IDD2NS 30 30 30 IDD2P 5 5 5 IDD2PS 5 5 5 IDD3N 65 65 65 IDD3NS 45 45 45 IDD4 150 150 150 3, 4 IDD5 200 200 200 3 IDD6 6 6 6 Unit Note 3 mA FEBRUARY 2011 AS4C16M16S 256Mb / 16M x 16 bit Synchronous DRAM (SDRAM) Table 16. Electrical Characteristics and Recommended A.C. Operating Conditions (VDD = 3.3V0.3V, TA = 0~70C) (Note: 5, 6, 7, 8) Symbol tRC tRFC tRCD tRP tRRD tMR D tRAS tWR -6 -5 A.C. Parameter -7 Unit Note Min. Max. Min. Max. Min. Max. 55 - 60 - 63 - 55 - 60 - 63 - 15 - 18 - 21 - 15 - 18 - 21 - 10 - 12 - 14 - 10 - 12 - 14 - 40 120K 42 120K 49 120K 10 - 12 - 14 CL* = 2 10 - 12 - 12 - CL* = 3 5 - 6 - 7 - Row cycle time (same bank) Refresh cycle time RAS# to CAS# delay (same bank) Precharge to refresh/row activate command (same bank) Row activate to row activate delay (different banks) Mode register set cycle time Row activate to precharge time (same bank) Write recovery time ns 9 tCK Clock cycle time tCH Clock high time 2 - 2.5 - 2.5 tCL Clock low time 2 - 2.5 - 2.5 - tAC Access time from CLK (positive edge) CL* = 2 - - - - - 6.5 CL* = 3 - 4.5 - 5.4 - 5.4 tOH Data output hold time 2 - 2 - 2 - tLZ Data output low impedance 0 - 0 - 0 - tHZ Data output high impedance - 4.5 - 5.4 - 5.4 8 tIS Data/Address/Control Input set-up time 1.5 - 1.5 - 1.5 - 10 tIH Data/Address/Control Input hold time 1 - 1 - 1 - 10 tPDE Power Down Exit set-up time tIS+tCK - tIS+tCK - tIS+tCK - tREFI Average Refresh interval time - 7.8 - 7.8 - 7.8 s tXSR Exit Self-Refresh to Read Command tRC+tIS - tRC+tIS - tRC+tIS - ns 10 10 10 9 * CL is CAS Latency. Note: 1. Stress greater than those listed under "Absolute Maximum Ratings" may cause permanent damage to the device. SS. VIH (Max) = 4.6V for pulse width 3ns. VIL (Min) = -1.5V for pulse width 3ns. 2. All voltages are referenced to V 3. These parameters depend on the cycle rate and these values are measured by the cycle rate under the minimum value of tCK and tRC. Input signals are changed one time during every 2 tCK. 4. These parameters depend on the output loading. Specified values are obtained with the output open. 5. Power-up sequence is described in Note 11. 6. A.C. Test Conditions 19 FEBRUARY 2011 AS4C16M16S 256Mb / 16M x 16 bit Synchronous DRAM (SDRAM) Table 17. LVTTL Interface Reference Level of Output Signals 1.4V / 1.4V Output Load Reference to the Under Output Load (B) Input Signal Levels 2.4V / 0.4V Transition Time (Rise and Fall) of Input Signals 1ns Reference Level of Input Signals 1.4V 7. Transition times are measured between VIH and VIL. Transition (rise and fall) of input signals are in a fixed slope (1 ns). 8. tHZ defines the time in which the outputs achieve the open circuit condition and are not at reference levels. 9. If clock rising time is longer than 1 ns, (tR / 2 -0.5) ns should be added to the parameter. 10. Assumed input rise and fall time tT (tR & tF) = 1 ns If t R or t F is longer than 1 ns, transient time compensation should be considered, i.e., [(tr + tf)/2 - 1] ns should be added to the parameter. 11. Power up Sequence Power up must be performed in the following sequence. 1) Power must be applied to VDD and VDDQ (simultaneously) when CKE= "L", DQM= "H" and all input signals are held "NOP" state. 2) Start clock and maintain stable condition for minimum 200s, then bring CKE= "H" and, it is recommended that DQM is held "HIGH" (VDD levels) to ensure DQ output is in high impedance. 3) All banks must be precharged. 4) Mode Register Set command must be asserted to initialize the Mode register. 5) A minimum of 2 Auto-Refresh dummy cycles must be required to stabilize the internal circuitry of the device. * The Auto Refresh command can be issue before or after Mode Register Set command 20 FEBRUARY 2011 AS4C16M16S 256Mb / 16M x 16 bit Synchronous DRAM (SDRAM) Timing Waveforms Figure 19. AC Parameters for Write Timing (Burst Length=4) T0 CLK T1 T2 T3 T4 T5 T6 T7 T8 T9 T10 T11 T12 T13 T14 T15 T16 T17 T18 T19 T20 T21 T22 tCH tCL CKE tIS tIS Begin Auto Precharge Bank A tIH Begin Auto Precharge Bank B CS# RAS# CAS# WE# BA0,1 tIH A10 RAx RBx RAy tIS A0-A9, A11-A12 RAx CAx RBx CBx RAy CAy DQM tRCD tDAL tIS tRC DQ Ax0 Activate Command Bank A Ax1 Write with Auto Precharge Command Bank A Ax2 Activate Command Bank B tWR tIH Hi-Z Ax3 Bx0 Bx1 Bx2 Write with Auto Precharge Command Bank B Bx3 Ay0 Activate Command Bank A Write Command Bank A Ay1 Ay2 Ay3 Precharge Command Bank A Don't Care 21 FEBRUARY 2011 AS4C16M16S 256Mb / 16M x 16 bit Synchronous DRAM (SDRAM) Figure 20. AC Parameters for Read Timing (Burst Length=2, CAS# Latency=2) T0 CLK T1 T2 T3 T4 T5 T6 T7 T8 T9 T10 T11 T12 T13 T14 T15 T16 tCH tCL CKE tIS Begin Auto Precharge Bank B tIS tIH tIH CS# RAS# CAS# WE# BA0,1 tIH A10 RAx RBx RAy tIS A0-A9, A11-A12 RAx CAx RBx CBx RAy tRRD tRAS DQM tRC tAC tRCD DQ tRP tHZ tLZ Hi-Z Ax0 Bx0 Ax1 tHZ tOH Activate Command Bank A Read Command Bank A Activate Command Bank B Bx1 Read with Precharge Auto Precharge Command Command Bank A Bank B Activate Command Bank A Don't Care 22 FEBRUARY 2011 AS4C16M16S 256Mb / 16M x 16 bit Synchronous DRAM (SDRAM) Figure 21. Auto Refresh (Burst Length=4, CAS# Latency=2) T0 T1 T2 T3 T4 T5 T6 T7 T8 T9 T10 T11 T12 T13 T14 T15 T16 T17 T18 T19 T20 T21 T22 CLK CKE CS# RAS# CAS# WE# BA0,1 A10 RAx A0-A9, A11-A12 RAx tRP tRC tRC CAx tRCD DQM DQ Ax0 Precharge All Command Auto Refresh Command Activate Command Bank A Auto Refresh Command Ax1 Read Command Bank A Don't Care 23 FEBRUARY 2011 AS4C16M16S 256Mb / 16M x 16 bit Synchronous DRAM (SDRAM) Figure 22. Power on Sequence and Auto Refresh T0 T1 T2 T3 T4 T5 T6 T7 T8 T9 T10 T11 T12 T13 T14 T15 T16 T17 T18 T19 T20 T21 T22 CLK CKE High Level Is reguired Minimum for 2 Refresh Cycles are required CS# RAS# CAS# WE# BA0,1 A10 Address Key A0-A9 A11-A12 DQM DQ tRP tMRD Hi-Z Precharge All Command Inputs must be Stable for 200s 1st Auto Refresh(*) Command 2nd Auto Refresh(*) Command Mode Register Set Command Any Command Don't Care Note(*): The Auto Refresh command can be issue before or after Mode Register Set command 24 FEBRUARY 2011 AS4C16M16S 256Mb / 16M x 16 bit Synchronous DRAM (SDRAM) Figure 23. Self Refresh Entry & Exit Cycle T0 T1 T2 T3 T4 T5 T6 T7 T8 T9 T10 T11 T12 T13 T14 T15 T16 T17 T18 T19 CLK *Note 2 CKE tXSR *Note 5 *Note 1 *Note 3,4 *Note 8 tPDE tIS tIH *Note 6 tIS *Note 7 CS# RAS# *Note 9 CAS# WE# BA0,1 A10 A0-A9, A11-A12 DQM DQ Hi-Z Hi-Z Self Refresh Exit Self Refresh Entry Auto Refresh Don't Care Note: To Enter SelfRefresh Mode 1. CS#, RAS# & CAS# with CKE should be low at the same clock cycle. 2. After 1 clock cycle, all the inputs including the system clock can be don't care except for CKE. 3. The device remains in SelfRefresh mode as long as CKE stays "low". 4. Once the device enters SelfRefresh mode, minimum tRAS is required before exit from SelfRefresh. 5. 6. 7. 8. 9. To Exit SelfRefresh Mode System clock restart and be stable before returning CKE high. Enable CKE and CKE should be set high for valid setup time and hold time. CS# starts from high. Minimum tXSR is required after CKE going high to complete SelfRefresh exit. 4096 cycles of burst AutoRefresh is required before SelfRefresh entry and after SelfRefresh exit if the system uses burst refresh. 25 FEBRUARY 2011 AS4C16M16S 256Mb / 16M x 16 bit Synchronous DRAM (SDRAM) Figure 24.1. Clock Suspension During Burst Read (Using CKE) (Burst Length=4, CAS# Latency=2) T0 T1 T2 T3 T4 T5 T6 T7 T8 T9 T10 T11 T12 T13 T14 T15 T16 T17 T18 T19 T20 T21 T22 CLK CKE CS# RAS# CAS# WE# BA0,1 A10 RAx A0-A9, A11-A12 RAx CAx DQM DQ tHZ Hi-Z Ax0 Activate Command Bank A Read Command Bank A Ax1 Clock Suspend 1 Cycle Ax2 Ax3 Clock Suspend 2 Cycles Clock Suspend 3 Cycles Don't Care 26 FEBRUARY 2011 AS4C16M16S 256Mb / 16M x 16 bit Synchronous DRAM (SDRAM) Figure 24.2. Clock Suspension During Burst Read (Using CKE) (Burst Length=4, CAS# Latency=3) T0 T1 T2 T3 T4 T5 T6 T7 T8 T9 T10 T11 T12 T13 T14 T15 T16 T17 T18 T19 T20 T21 T22 CLK CKE CS# RAS# CAS# WE# BA0,1 A10 RAx A0-A9, A11-A12 RAx CAx DQM DQ tHZ Hi-Z Ax0 Activate Command Bank A Read Command Bank A Ax1 Clock Suspend 1 Cycle Ax2 Ax3 Clock Suspend 2 Cycles Clock Suspend 3 Cycles Don't Care 27 FEBRUARY 2011 AS4C16M16S 256Mb / 16M x 16 bit Synchronous DRAM (SDRAM) Figure 25. Clock Suspension During Burst Write (Using CKE) (Burst Length=4) T0 T1 T2 T3 T4 T5 T6 T7 T8 T9 T10 T11 T12 T13 T14 T15 T16 T17 T18 T19 T20 T21 T22 CLK CKE CS# RAS# CAS# WE# BA0,1 A10 RAx A0-A9, A11-A12 RAx CAx DQM DQ Hi-Z DAx0 Activate Command Bank A DAx1 Clock Suspend 1 Cycle Write Command Bank A DAx2 Clock Suspend 2 Cycles DAx3 Clock Suspend 3 Cycles Don't Care 28 FEBRUARY 2011 AS4C16M16S 256Mb / 16M x 16 bit Synchronous DRAM (SDRAM) Figure 26. Power Down Mode and Clock Suspension (Burst Length=4, CAS# Latency=2) T0 T1 T2 T3 T4 CLK T5 T6 T7 T8 T9 T10 T11 T12 T13 T14 T15 T16 T17 T18 T19 T20 T21 T22 tIH tIS tPDE CKE Valid CS# RAS# CAS# WE# BA0,1 A10 RAx A0-A9, A11-A12 RAx CAx DQM DQ tHZ Hi-Z Ax0 ACTIVE Activate Read STANDBY Command Command Bank A Bank A Power Down Power Down Mode Exit Mode Entry Ax1 Clock Suspension Start Ax2 Ax3 Clock Suspension End Precharge Command Bank A Power Down Mode Entry 29 PRECHARGE STANDBY Power Down Mode Exit Any Command Don't Care FEBRUARY 2011 AS4C16M16S 256Mb / 16M x 16 bit Synchronous DRAM (SDRAM) Figure 27.1. Random Column Read (Page within same Bank) (Burst Length=4, CAS# Latency=2) T0 T1 T2 T3 T4 T5 T6 T7 T8 T9 T10 T11 T12 T13 T14 T15 T16 T17 T18 T19 T20 T21 T22 CLK CKE CS# RAS# CAS# WE# BA0,1 A10 RAw A0-A9, A11-A12 RAw RAz CAw CAx CAy RAz CAz DQM DQ Hi-Z Aw0 Activate Command Bank A Read Command Bank A Aw1 Aw2 Aw3 Read Command Bank A Ax0 Ax1 Ay0 Ay1 Ay2 Ay3 Precharge Command Bank A Read Command Bank A Az0 Activate Command Bank A Read Command Bank A Don't Care 30 FEBRUARY 2011 AS4C16M16S 256Mb / 16M x 16 bit Synchronous DRAM (SDRAM) Figure 27.2. Random Column Read (Page within same Bank) (Burst Length=4, CAS# Latency=3) T0 T1 T2 T3 T4 T5 T6 T7 T8 T9 T10 T11 T12 T13 T14 T15 T16 T17 T18 T19 T20 T21 T22 CLK CKE CS# RAS# CAS# WE# BA0,1 A10 RAw A0-A9, A11-A12 RAw RAz CAw CAx CAy RAz CAz DQM DQ Hi-Z Aw0 Activate Command Bank A Read Command Bank A Aw1 Aw2 Read Command Bank A Aw3 Ax0 Ax1 Ay0 Ay1 Ay2 Precharge Command Bank A Read Command Bank A Ay3 Activate Command Bank A Read Command Bank A Don't Care 31 FEBRUARY 2011 AS4C16M16S 256Mb / 16M x 16 bit Synchronous DRAM (SDRAM) Figure 28. Random Column Write (Page within same Bank) (Burst Length=4) T0 T1 T2 T3 T4 T5 T6 T7 T8 T9 T10 T11 T12 T13 T14 T15 T16 T17 T18 T19 T20 T21 T22 CLK CKE CS# RAS# CAS# WE# BA0,1 A10 RBw A0-A9, A11-A12 RBw RBz CBw CBx CBy RBz CBz DQM DQ Hi-Z DBw0 DBw1 DBw2 DBw3 DBx0 Activate Command Bank B Write Command Bank B DBx1 Write Command Bank B DBy0 DBy1 DBy2 DBy3 DBz0 Precharge Command Bank B Write Command Bank B Activate Command Bank B DBz1 Write Command Bank B Don't Care 32 FEBRUARY 2011 AS4C16M16S 256Mb / 16M x 16 bit Synchronous DRAM (SDRAM) Figure 29.1. Random Row Read (Interleaving Banks) (Burst Length=8, CAS# Latency=2) T0 T1 T2 T3 T4 T5 T6 T7 T8 T9 T10 T11 T12 T13 T14 T15 T16 T17 T18 T19 T20 T21 T22 CLK CKE High CS# RAS# CAS# WE# BA0,1 A10 RBx A0-A9, A11-A12 RBx CBx RBy RAx CAx RBy tAC tRCD DQM DQ RAx CBy tRP Hi-Z Bx0 Activate Command Bank B Read Command Bank B Bx1 Bx2 Bx3 Bx4 Bx5 Activate Command Bank A Bx6 Bx7 Ax0 Read Command Bank A Precharge Command Bank B 33 Ax1 Ax2 Ax3 Activate Command Bank B Ax4 Ax5 Ax6 Ax7 Read Command Bank B Don't Care FEBRUARY 2011 AS4C16M16S 256Mb / 16M x 16 bit Synchronous DRAM (SDRAM) Figure 29.2. Random Row Read (Interleaving Banks) (Burst Length=8, CAS# Latency=3) T0 T1 T2 T3 T4 T5 T6 T7 T8 T9 T10 T11 T12 T13 T14 T15 T16 T17 T18 T19 T20 T21 T22 CLK CKE High CS# RAS# CAS# WE# BA0,1 A10 RBx A0-A9, A11-A12 RBx CBx RBy RAx CAx RBy tAC tRCD DQM DQ RAx CBy tRP Hi-Z Bx0 Activate Command Bank B Read Command Bank B Bx1 Bx2 Bx3 Activate Command Bank A Bx4 Bx5 Bx6 Read Command Bank A Bx7 Ax0 Precharge Command Bank B Ax1 Ax2 Ax3 Activate Command Bank B Ax4 Ax5 Ax6 Read Command Bank B Ax7 By0 Precharge Command Bank A Don't Care 34 FEBRUARY 2011 AS4C16M16S 256Mb / 16M x 16 bit Synchronous DRAM (SDRAM) Figure 30. Random Row Write (Interleaving Banks) (Burst Length=8) T0 T1 T2 T3 T4 T5 T6 T7 T8 T9 T10 T11 T12 T13 T14 T15 T16 T17 T18 T19 T20 T21 T22 CLK CKE High CS# RAS# CAS# WE# BA0,1 A10 RAx A0-A9, A11-A12 RAx CAx RAy RBx CBx tRCD DQM DQ RBx RAy tWR* CAy tRP tWR* Hi-Z DAx0 Activate Command Bank A DAx1 DAx2 DAx3 Write Command Bank A DAx4 DAx5 DAx6 Activate Command Bank B DAx7 DBx0 DBx1 DBx2 DBx3 Write Command Bank B Precharge Command Bank A DBx4 DBx5 DBx6 Activate Command Bank A DBx7 DAy0 DAy1 DAy2 Write Command Bank A DAy3 Precharge Command Bank B Don't Care *tWR>tWR (min.) 35 FEBRUARY 2011 AS4C16M16S 256Mb / 16M x 16 bit Synchronous DRAM (SDRAM) Figure 31.1. Read and Write Cycle (Burst Length=4, CAS# Latency=2) T0 T1 T2 T3 T4 T5 T6 T7 T8 T9 T10 T11 T12 T13 T14 T15 T16 T17 T18 T19 T20 T21 T22 CLK CKE CS# RAS# CAS# WE# BA0,1 A10 RAx A0-A9, A11-A12 RAx CAx CAy CAz DQM DQ Hi-Z Ax0 Activate Command Bank A Read Command Bank A Ax1 Ax2 Ax3 DAy0 DAy1 Write Command Bank A DAy3 The Write Data is Masked with a Zero Clock Latency Az0 Read Command Bank A Az1 Az3 The Read Data is Masked with a Two Clock Latency Don't Care 36 FEBRUARY 2011 AS4C16M16S 256Mb / 16M x 16 bit Synchronous DRAM (SDRAM) Figure 31.2. Read and Write Cycle (Burst Length=4, CAS# Latency=3) T0 T1 T2 T3 T4 T5 T6 T7 T8 T9 T10 T11 T12 T13 T14 T15 T16 T17 T18 T19 T20 T21 T22 CLK CKE CS# RAS# CAS# WE# BA0,1 A10 RAx A0-A9, A11-A12 RAx CAx CAy CAz DQM DQ Hi-Z Ax0 Activate Command Bank A Read Command Bank A Ax1 Ax2 Ax3 DAy0 DAy1 Write Command Bank A 37 DAy3 The Write Data is Masked with a Zero Clock Read Latency Command Bank A Az0 Az1 Az3 The Read Data is Masked with a Two Clock Latency Don't Care FEBRUARY 2011 AS4C16M16S 256Mb / 16M x 16 bit Synchronous DRAM (SDRAM) Figure 32.1. Interleaving Column Read Cycle (Burst Length=4, CAS# Latency=2) T0 T1 T2 T3 T4 T7 T8 T9 T10 T11 T12 T13 T14 T15 T16 T17 T18 T19 T20 T21 T22 T5 T6 CLK CKE CS# RAS# CAS# WE# BA0,1 A10 RAx A0-A9, A11-A12 RAx RBx CAy RBx CBw CBx Ax3 Bw0 CBy CAy CBz tRCD DQM tAC DQ Hi-Z Ax0 Activate Command Bank A Read Command Bank A Ax1 Activate Command Bank B Ax2 Read Command Bank B Bw1 Read Command Bank B Bx0 Bx1 Read Command Bank B By0 By1 Read Command Bank A Ay0 Ay1 Read Command Bank B Bz0 Bz1 Precharge Command Bank A Bz2 Bz3 Precharge Command Bank B Don't Care 38 FEBRUARY 2011 AS4C16M16S 256Mb / 16M x 16 bit Synchronous DRAM (SDRAM) Figure 32.2. Interleaved Column Read Cycle (Burst Length=4, CAS# Latency=3) T0 T1 T2 T3 T4 T5 T6 T7 T8 T9 T10 T11 T12 T13 T14 T15 T16 T17 T18 T19 T20 T21 T22 CLK CKE CS# RAS# CAS# WE# BA0,1 A10 RAx A0-A9, A11-A12 RAx RBx CAx RBx CBx CBy CBz CAy tRCD DQM tAC DQ Hi-Z Ax0 Activate Command Bank A Read Command Bank A Activate Command Bank B Ax1 Ax2 Read Command Bank B Ax3 Bx0 Read Command Bank B Bx1 By0 Read Command Bank B By1 Bz0 Read Command Bank A Bz1 Ay0 Precharge Command Bank B Ay1 Ay2 Ay3 Precharge Command Bank A Don't Care 39 FEBRUARY 2011 AS4C16M16S 256Mb / 16M x 16 bit Synchronous DRAM (SDRAM) Figure 33. Interleaved Column Write Cycle (Burst Length=4) T0 T1 T2 T3 T4 T5 T6 T7 T8 T9 T10 T11 T12 T13 T14 T15 T16 T17 T18 T19 T20 T21 T22 CLK CKE CS# RAS# CAS# WE# BA0,1 A10 RAx A0-A9, A11-A12 RBw RAx CAx RBw CBw CBx CBy CAy CBz tWR tRCD tWR DQM tRRD>tRRD (min) DQ Hi-Z DAx0 Activate Command Bank A DAx1 DAx2 DAx3 DBw0 DBw1 DBx0 DBx1 DBy0 Write Command Bank A Activate Command Bank B Write Command Bank B Write Command Bank B DBy1 Write Command Bank B 40 DAy0 DAy1 DBz0 Write Command Bank A DBz1 DBz2 Write Command Bank B Precharge Command Bank A DBz3 Precharge Command Bank B Don't Care FEBRUARY 2011 AS4C16M16S 256Mb / 16M x 16 bit Synchronous DRAM (SDRAM) Figure 34.1. Auto Precharge after Read Burst (Burst Length=4, CAS# Latency=2) T0 T1 T2 T3 T4 T5 T6 T7 T8 T9 T10 T11 T12 T13 T14 T15 T16 T17 T18 T19 T20 T21 T22 CLK CKE Begin Auto Precharge Bank B High Begin Auto Precharge Bank A CS# RAS# CAS# WE# BA0,1 A10 RAx A0-A9, A11-A12 RAx RBx CAx RBy RBx CBx CAy RBy CBy RAz tRP DQM DQ RAz Hi-Z Ax0 Activate Command Bank A Read Command Bank A Ax1 Activate Command Bank B Ax2 Ax3 Read with Auto Precharge Command Bank B Bx0 Bx1 Bx2 Bx3 Read with Auto precharge Command Bank A Ay0 Ay1 Ay2 Activate Command Bank B Ay3 By0 By1 By2 Read with Activate Auto Precharge Command Command Bank A Bank B Don't Care 41 FEBRUARY 2011 AS4C16M16S 256Mb / 16M x 16 bit Synchronous DRAM (SDRAM) Figure 34.2. Auto Precharge after Read Burst (Burst Length=4, CAS# Latency=3) T0 T1 T2 T3 T4 T5 T6 T7 T8 T9 T10 T11 T12 T13 T14 T15 T16 T17 T18 T19 T20 T21 T22 CLK CKE Begin Auto Precharge Bank A Begin Auto Precharge Bank B High CS# RAS# CAS# WE# BA0,1 A10 RAx A0-A9, A11-A12 RAx RBy RBx CAx RBx CBx CAy RBy CBy tRP DQM DQ Hi-Z Ax0 Activate Command Bank A Read Command Bank A Activate Command Bank B Ax1 Ax2 Read with Auto Precharge Command Bank B Ax3 Bx0 Bx1 Bx2 Read with Auto Precharge Command Bank A Bx3 Ay0 Ay1 Activate Command Bank B Ay2 Ay3 By0 By1 By2 Read with Auto Precharge Command Bank B Don't Care 42 FEBRUARY 2011 AS4C16M16S 256Mb / 16M x 16 bit Synchronous DRAM (SDRAM) Figure 35. Auto Precharge after Write Burst (Burst Length = 4) T0 T1 T2 T3 T4 T5 T6 T7 T8 T9 T10 T11 T12 T13 T14 T15 T16 T17 T18 T19 T20 T21 T22 CLK CKE Begin Auto Precharge Bank A Begin Auto Precharge Bank B High CS# RAS# CAS# WE# BA0,1 A10 RAx A0-A9, A11-A12 RAx RBy RBx CAx RBx CBx CAy RBy CBy tDAL DQM DQ Hi-Z DAx0 DAx1 Activate Command Bank A DAx2 Write Command Bank A Activate Command Bank B DAx3 DBx0 DBx1 DBx2 Write with Auto Precharge Command Bank B DBx3 DAy0 DAy1 DAy2 Write with Auto Precharge Command Bank A DAy3 DBy0 DBy1 DBy2 Activate Command Bank B DBy3 Write with Auto Precharge Command Bank B Don't Care 43 FEBRUARY 2011 AS4C16M16S 256Mb / 16M x 16 bit Synchronous DRAM (SDRAM) Figure 36.1. Full Page Read Cycle (Burst Length=Full Page, CAS# Latency=2) T0 T1 T2 T3 T4 T5 T6 T7 T8 T9 T10 T11 T12 T13 T14 T15 T16 T17 T18 T19 T20 T21 T22 CLK CKE High CS# RAS# CAS# WE# BA0,1 A10 RAx A0-A9, A11-A12 RAx RBy RBx CAx RBx CBx RBy tRP DQM DQ Hi-Z Ax Activate Command Bank A Read Command Bank A Ax+1 Ax+2 Ax-2 Ax-1 Ax Ax+1 Bx Bx+1 Bx+2 Bx+3 The burst counter wraps Activate Read Command from the highest order Command page address back to zero Bank B Bank B during this time interval Bx+4 Bx+5 Bx+6 Precharge Command Bank B Full Page burst operation does not terminate when the burst length is satisfied; the burst counter increments and continues Bursting beginning with the starting address 44 Burst Stop Command Activate Command Bank B Don't Care FEBRUARY 2011 AS4C16M16S 256Mb / 16M x 16 bit Synchronous DRAM (SDRAM) Figure 36.2. Full Page Read Cycle (Burst Length=Full Page, CAS# Latency=3) T0 T1 T2 T3 T4 T5 T6 T7 T8 T9 T10 T11 T12 T13 T14 T15 T16 T17 T18 T19 T20 T21 T22 CLK CKE High CS# RAS# CAS# WE# BA0,1 A10 RAx A0-A9, A11-A12 RAx RBy RBx CAx RBx CBx RBy tRP DQM DQ Hi-Z Ax Activate Command Bank A Read Command Bank A Activate Command Bank B Ax+1 Ax+2 Ax-2 Ax-1 Ax Ax+1 Bx Bx+1 Bx+2 Read Command Bank B Bx+3 Bx+4 Bx+5 Precharge Command Bank B The burst counter wraps from the highest order page address back to zero during this time interval Burst Stop Command Full Page burst operation does not terminate when the burst length is satisfied; the burst counter increments and continues Bursting beginning with the starting address 45 Activate Command Bank B Don't Care FEBRUARY 2011 AS4C16M16S 256Mb / 16M x 16 bit Synchronous DRAM (SDRAM) Figure 37. Full Page Write Cycle (Burst Length=Full Page) T0 T1 T2 T3 T4 T5 T6 T7 T8 T9 T10 T11 T12 T13 T14 T15 T16 T17 T18 T19 T20 T21 T22 CLK CKE High CS# RAS# CAS# WE# BA0,1 A10 RAx A0-A9, A11-A12 RAx RBy RBx CAx RBx CBx RBy DQM Data is ignored DQ Hi-Z DAx Activate Command Bank A DAx+1 Write Command Bank A DAx+2 DAx+3 DAx-1 DAx DAx+1 Activate Command Bank B The burst counter wraps from the highest order page address back to zero during this time interval DBx DBx+1 DBx+2 DBx+3 DBx+4 DBx+5 Write Command Bank B Full Page burst operation does not terminate when the burst length is satisfied; the burst counter increments and continues bursting beginning with the starting address 46 Precharge Command Bank B Burst Stop Command Activate Command Bank B Don't Care FEBRUARY 2011 AS4C16M16S 256Mb / 16M x 16 bit Synchronous DRAM (SDRAM) Figure 38. Byte Write Operation (Burst Length=4, CAS# Latency=2) T0 T1 T2 T3 T4 T5 T6 T7 T8 T9 T10 T11 T12 T13 T14 T15 T16 T17 T18 T19 T20 T21 T22 CLK CKE High CS# RAS# CAS# WE# BA0,1 A10 RAx A0-A9, A11-A12 RAx CAx CAy CAz LDQM UDQM DQ0-DQ7 Ax0 DQ8-DQ15 Activate Command Bank A Read Command Bank A Ax1 Ax2 Ax1 Ax2 Upper Byte is masked DAy1 Ax3 Lower Byte is masked DAy0 Day2 DAy1 Write Command Bank A DAy3 Upper Byte is masked Az0 Read Command Bank A Az1 Az2 Az1 Az2 Lower Byte is masked Az3 Lower Byte is masked Don't Care 47 FEBRUARY 2011 AS4C16M16S 256Mb / 16M x 16 bit Synchronous DRAM (SDRAM) Figure 39. Random Row Read (Interleaving Banks) (Burst Length=4, CAS# Latency=2) T0 T1 T2 T3 T4 T5 T6 T7 T8 T9 T10 T11 T12 T13 T14 T15 T16 T17 T18 T19 T20 T21 T22 CLK CKE Begin Auto Precharge Bank B Begin Auto Precharge Bank A Begin Auto Precharge Bank B High Begin Auto Precharge Bank A CS# RAS# CAS# WE# BA0,1 A10 RBu A0-A9, A11-A12 RBu RAu CBu RAu CAu RBw RAv RBv RBv CBv tRP RAv CAv RBw tRP tRP DQM DQ Bu0 Activate Command Bank B Activate Command Read Bank A Bank B with Auto Precharge Bu1 Bu2 Bu3 Read Bank A with Auto Precharge Au0 Au1 Au2 Au3 Bv0 Activate Command Bank A Activate Command Bank B Read Bank B with Auto Precharge 48 Bv1 Bv2 Bv3 Read Bank A with Auto Precharge Av0 Av1 Av2 Av3 Activate Command Bank B Don't Care FEBRUARY 2011 AS4C16M16S 256Mb / 16M x 16 bit Synchronous DRAM (SDRAM) Figure 40. Full Page Random Column Read (Burst Length=Full Page, CAS# Latency=2) T0 T1 T2 T3 T4 T5 T6 T7 T8 T9 T10 T11 T12 T13 T14 T15 T16 T17 T18 T19 T20 T21 T22 CLK CKE CS# RAS# CAS# WE# BA0,1 A10 RAx RBx A0-A9, A11-A12 RAx RBx RBw CAx CBx CBy CAy CAz CBz RBw tRP DQM tRRD DQ tRCD Hi-Z Ax0 Activate Command Bank A Ax1 Bx0 Activate Read Command Command Bank B Bank B Read Read Command Command Bank A Bank A Ay0 Ay1 Read Command Bank B By0 By1 Read Command Bank A Az0 Az1 Az2 Read Command Bank B Bz0 Bz1 Bz2 Precharge Activate Command Bank B Command (Precharge Temination) Bank B Don't Care 49 FEBRUARY 2011 AS4C16M16S 256Mb / 16M x 16 bit Synchronous DRAM (SDRAM) Figure 41. Full Page Random Column Write (Burst Length=Full Page) T0 T1 T2 T3 T4 T5 T6 T7 T8 T9 T10 T11 T12 T13 T14 T15 T16 T17 T18 T19 T20 T21 T22 CLK CKE CS# RAS# CAS# WE# BA0,1 A10 RAx RBx A0-A9, A11-A12 RAx RBx RBw CAx CBx CBy CAy CAz CBz RBw tWR tRP DQM tRRD DQ tRCD Hi-Z DAx0 Activate Command Bank A DAx1 Activate Command Bank B Write Command Bank A DBx0 DAy0 DAy1 Write Command Bank B Write Command Bank A DBy0 DBy1 Write Command Bank B DAz0 DAz1 DAz2 Write Command Bank A DBz0 DBz1 DBz2 Precharge Activate Command Bank B Command (Precharge Temination) Bank B Write Command Bank B Write Data are masked Don't Care Figure 42. Precharge Termination of a Burst (Burst Length=4, 8 or Full Page, CAS# Latency=3) T0 T1 T2 T3 T4 T5 T6 T7 T8 T9 T10 T11 T12 T13 T14 T15 T16 T17 T18 T19 T20 T21 T22 CLK CKE High CS# RAS# CAS# WE# BA0,1 A10 RAx A0-A9, A11-A12 RAx RAy CAx RAz RAy tWR CAy RAz tRP tRP DQM DQ DAx0 Activate Command Bank B DAx1 Precharge Write Command Command Bank A Bank A Precharge Termination of a Write Burst Write Data are masked Ay0 Activate Command Bank A Read Command Bank A Ay1 Precharge Command Bank A Ay2 Activate Command Bank A Precharge Termination of a Read Burst Don't Care 50 FEBRUARY 2011 AS4C16M16S 256Mb / 16M x 16 bit Synchronous DRAM (SDRAM) Symbol A A1 A2 B C D E e HE L L1 S y Min --0.002 0.035 0.010 0.004 0.87 0.395 --0.455 0.016 ----0 Dimension in inch Nom Max Min Dimension in mm Nom Max ----0.039 0.014 0.006 0.875 0.400 0.031 0.463 --0.032 0.028 ----- 0.047 0.008 0.043 0.018 0.008 0.88 0.405 --0.471 0.024 ----0.004 8 --0.05 0.9 0.25 0.12 22.09 10.03 --11.56 0.4 ------0 ----1.0 0.35 0.165 22.22 10.16 0.8 11.76 0.5 0.84 0.71 ----- 1.2 0.2 1.1 0.45 0.21 22.35 10.29 --11.96 0.6 ----0.1 8 Notes: 1. Dimension D&E do not include interlead flash. 2. Dimension B does not include dambar protrusion/intrusion. 3. Dimension S includes end flash. 4. Controlling dimension: mm 51 FEBRUARY 2011 AS4C16M16S 256Mb / 16M x 16 bit Synchronous DRAM (SDRAM) ORDERING INFORMATION Alliance Organization VCC Range Package Operating Temp Speed MHz AS4C16M16S-5TCN 16M x 16 3.3V+/-0.3V 54 TSOP II Commercial 200 AS4C16M16S-6TCN 16M x 16 3.3V+/-0.3V 54 TSOP II Commercial 166 AS4C16M16S-6TIN 16M x 16 3.3V+/-0.3V 54 TSOP II Industrial 166 AS4C16M16S-7TCN 16M x 16 3.3V+/-0.3V 54 TSOP II Commercial 143 PART NUMBERING SYSTEM AS4C 16M16S 4M4 S= SDRAM SDRAM prefix 256Mb (16Mx16) -7 Speed T=TSOP Package 54 pin TSOP II 52 C N Temperature Range N = Lead Free RoHS C = Commercial compliant part (0 - 70C) I = Industrial (-45 - 85C)