View IBM0325404CT3A-75A_1475347.PDF datasheet online --- IC-ON-LINE

Datasheet File OCR Text:

ibm0325404 ibm0325804 ibm0325164 ibm03254b4 ec update (-10) 256mb synchronous dram - die revision a 29l0000.e36980a 7/99 ?ibm corporation. all rights reserved. use is further subject to the provisions at the end of this document. page 1 of 68 features ? high performance: ? single-pulsed ras interface ? fully synchronous to positive clock edge ? four banks controlled by bs0, bs1 (bank selects) ? programmable cas latency: 2, 3 ? programmable burst length: 1, 2, 4, or 8 ? programmable wrap: sequential or interleave ? multiple burst read with single write option ? automatic and controlled precharge command ? data mask for read/write control (x4, x8) and dual data mask for byte control (x16) ? auto refresh (cbr) and self refresh ? suspend mode and power down mode ? standard power operation ? 8192 refresh cycles/64ms ? random column address every clk (1-n rule) ? single 3.3v 0.3v power supply ? lvttl compatible ? packages: - 54-pin 400 mil tsop-type ii - 66-pin 400 mil 2-high stack tsoj description the ibm0325404, ibm0325804, and ibm0325164 are four bank synchronous drams organized as 16mbi t x 4 i/o x 4 bank, 8mbi t x 8 i/o x 4 bank, and 4mbit x 16 i/ o x 4 bank, respectively. ibm03254b4, a stacked version of the x4 component, is also offered. these synchronous devices achieve high- speed data-transfer rates of up to 133 mhz by employing a pipeline chip architecture that synchro- nizes the output data to a system clock. the chip is fabricated with ibms advanced 256mbit single tran- sistor cmos dram process technology. the device is designed to comply with all jedec standards set for synchronous dram products, both electrically and mechanically. all the control, address, and data input/output (i/o or dq) circuits are synchronized with the positive edge of an exter- nally supplied clock. ras, cas, we, and cs are pulsed signals which are examined at the positive edge of each externally applied clock (clk). internal chip operating modes are defined by combinations of these signals, and a command decoder initiates the necessary timings for each operation. a fifteen-bit address bus accepts address data in the conventional ras/ cas multi- plexing style. thirteen row addresses (a0-a12) and two bank select addresses (bs0, bs1) are strobed with ras. eleven column addresses (a0-a9, a11) plus bank select addresses and a10 are strobed with cas. column address a11 is dropped on the x8 device and column addresses a9 and a11 are dropped on the x16 device. access to the lower or upper dram in a stacked device is controlled by cs0 and cs1. prior to any access, the cas latency, burst length, and sequence must be programmed into the device by address inputs a0-a12, bs0, bs1 during a mode register set cycle. it is also possible to program a multiple burst sequence with single write cycle for write-through cache operation. operating the four memory banks in an interleave fashion allows random access operation to occur at a higher rate than is possible with standard drams. a sequential and gapless data rate of up to 133 mhz is possible depending on burst length, cas latency, and speed grade of the device. simultaneous opera- tion of both decks of a stacked device is allowed, depending on the operation being done. auto refresh (cbr), and self refresh operation are supported. -75a cl=3 -260, cl=2 -360, cl=3 -10, cl=3 units f ck clock frequency 133 100 100 100 mhz t ck clock cycle 7.5 10 10 10 ns t ac clock access time 1 7 ns t ac clock access time 2 5.4 6 6 9 ns note: 1 terminated load, 2 unterminated load. see ac characteristics (page 39). .
ibm0325804 ibm0325404 ibm0325164 ibm03254b4 256mb synchronous dram - die revision a ec update (-10) ?ibm corporation. all rights reserved. use is further subject to the provisions at the end of this document. page 2 of 68 29l0000.e36980a 7/99 pin assignments for planar components (top view) 54-pin plastic tsop(ii) 400mil 16mbit x 4 i/o x 4 bank ibm0325404 1 2 3 4 5 6 9 10 11 12 13 14 7 8 15 16 17 18 19 20 21 22 54 53 52 51 50 49 46 45 44 43 42 41 48 47 40 39 38 37 36 35 34 33 v dd nc v ddq nc dq0 v ssq v ddq nc dq1 v ssq nc v dd nc nc nc we cas ras cs bs0 bs1 v ss nc v ssq nc dq3 v ddq v ssq nc dq2 v ddq nc v ss nc nc nc dqm clk cke a12 a11 a9 23 24 25 32 31 30 a10/ap a0 a1 a2 a8 a7 a6 a5 26 27 29 28 a3 v dd a4 v ss v dd dq0 v ddq nc dq1 v ssq v ddq nc dq3 v ssq nc v dd nc dq2 nc we cas ras cs bs0 bs1 a10/ap a0 a1 a2 a3 v dd v ss dq7 v ssq nc dq6 v ddq v ssq nc dq4 v ddq nc v ss nc dq5 nc dqm clk cke a12 a11 a9 a8 a7 a6 a5 a4 v ss v dd dq0 v ddq dq1 dq2 v ssq v ddq dq5 dq6 v ssq dq7 v dd dq3 dq4 ldqm we cas ras cs bs0 bs1 a10/ap a0 a1 a2 a3 v dd v ss dq15 v ssq dq14 dq13 v ddq v ssq dq10 dq9 v ddq dq8 v ss dq12 dq11 nc udqm clk cke a12 a11 a9 a8 a7 a6 a5 a4 v ss 4mbit x 16 i/o x 4 bank ibm0325164 8mbit x 8 i/o x 4 bank ibm0325804
ibm0325404 ibm0325804 ibm0325164 ibm03254b4 ec update (-10) 256mb synchronous dram - die revision a 29l0000.e36980a 7/99 ?ibm corporation. all rights reserved. use is further subject to the provisions at the end of this document. page 3 of 68 pin assignments for 2 high stack package (dual cs pin) (top view) 66-pin plastic tsoj 400mil 32mbit x 4 i/o x 4 bank (2 high stack) ibm03254b4 66 65 64 63 62 61 58 57 56 55 54 53 60 59 52 51 50 49 48 47 46 45 44 43 42 41 40 39 38 37 36 35 34 1 2 3 4 5 6 9 10 11 12 13 14 7 8 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 v ss nc v ssq nc dq3 v ddq v ssq nc dq2 v ddq nc nc nc nc v ssq nc nc nc v ss dqm nc ck cke0 3 cke1 4 a12 a11 a9 a8 a7 a6 a5 a4 v ss v dd nc v ddq nc dq0 v ssq v ddq nc dq1 v ssq nc nc nc nc v ddq nc nc v dd nc nc we cas ras cs0 1 cs1 2 bs0 bs1 a10/ap a0 a1 a2 a3 v dd notes 1. cs0 selects the lower sdram in the stack. 2. cs1 selects the upper sdram in the stack. 3. cke0 controls the clock for the lower sdram. 4. cke1 controls the clock for the upper sdram.
ibm0325804 ibm0325404 ibm0325164 ibm03254b4 256mb synchronous dram - die revision a ec update (-10) ?ibm corporation. all rights reserved. use is further subject to the provisions at the end of this document. page 4 of 68 29l0000.e36980a 7/99 pin description clk clock input dq0-dq15 data input/output cke (cke0, cke1) clock enable dqm, ldqm, udqm data mask cs ( cs0 , cs1 ) chip select vdd power (+3.3v) ras row address strobe vss ground cas column address strobe vddq power for dqs (+3.3v) we write enable vssq ground for dqs bs1, bs0 bank selects nc no connection a0 - a12 address inputs input/output functional description symbol type polarity function clk input positive edge the system clock input. all of the sdram inputs are sampled on the rising edge of the clock. cke, cke0, cke1 input active high activates the clk signal when high and deactivates the clk signal when low. by deactivating the clock, cke (cke0, cke1 for stacked devices) low initiates the power down mode, suspend mode, or the self refresh mode. cs, cs0, cs1 input active low cs ( cs0, cs1 for stacked devices) enables the command decoder when low and disables the command decoder when high. when the command decoder is disabled, new commands are ignored but previous operations continue. ras, cas we input active low when sampled at the positive rising edge of the clock, cas, ras, and we define the operation to be executed by the sdram. bs0, bs1 input selects which bank is to be active. a0 - a12 input during a bank activate command cycle, a0-a12 defines the row address (ra0-ra12) when sam- pled at the rising clock edge. during a read or write command cycle, a0-a9, a11 defines the column address (ca0-ca9, ca11) when sampled at the rising clock edge. a10 is used to invoke auto precharge operation at the end of the burst read or write cycle. if a10 is high, auto precharge is selected and bs0, bs1 defines the bank to be precharged. if a10 is low, auto precharge is disabled. during a precharge command cycle, a10 is used in conjunction with bs0, bs1 to control which bank(s) to precharge. if a10 is high, all banks will be precharged regardless of the state of bs. if a10 is low, then bs0 and bs1 are used to define which bank to precharge. dq0 - dq15 input- output data input/output pins operate in the same manner as on conventional drams. dqm ldqm udqm input active high the data input/output mask places the dq buffers in a high impedance state when sampled high. in x16 products, ldqm and udqm control the lower and upper byte i/o buffers, respectively. in read mode, dqm has a latency of two clock cycles and controls the output buffers like an output enable. dqm low turns the output buffers on and dqm high turns them off. in write mode, dqm has a latency of zero and operates as a word mask by allowing input data to be written if it is low but blocks the write operation if dqm is high. v dd , v ss supply power and ground for the input buffers and the core logic. v ddq , v ssq supply isolated power supply and ground for the output buffers to provide improved noise immunity.
ibm0325404 ibm0325804 ibm0325164 ibm03254b4 ec update (-10) 256mb synchronous dram - die revision a 29l0000.e36980a 7/99 ?ibm corporation. all rights reserved. use is further subject to the provisions at the end of this document. page 5 of 68 ordering information - planar devices (single cs pin) part number cas latencies power supply clock cycle package org. IBM0325404CT3A-75A 3 3.3v 7.5ns 400mil type ii tsop-54 x4 ibm0325404ct3a-260 2, 3 3.3v 10ns 400mil type ii tsop-54 x4 ibm0325404ct3a-360 2, 3 3.3v 10ns 400mil type ii tsop-54 x4 ibm0325404ct3a-10 2, 3 3.3v 10ns 400mil type ii tsop-54 x4 ibm0325804ct3a-75a 3 3.3v 7.5ns 400mil type ii tsop-54 x8 ibm0325804ct3a-260 2, 3 3.3v 10ns 400mil type ii tsop-54 x8 ibm0325804ct3a-360 2, 3 3.3v 10ns 400mil type ii tsop-54 x8 ibm0325804ct3a-10 2, 3 3.3v 10ns 400mil type ii tsop-54 x8 ibm0325164ct3a-360 2, 3 3.3v 10ns 400mil type ii tsop-54 x16 ordering information - 2 high stacked devices (dual cs pin) part number cas latencies power supply clock cycle package org. ibm03254b4ct3a-75a 3 3.3v 7.5ns 400mil type ii tsoj-66 x4 ibm03254b4ct3a-260 2, 3 3.3v 10ns 400mil type ii tsoj-66 x4 ibm03254b4ct3a-360 2, 3 3.3v 10ns 400mil type ii tsoj-66 x4 ibm03254b4ct3a-10 2, 3 3.3v 10ns 400mil type ii tsoj-66 x4
ibm0325804 ibm0325404 ibm0325164 ibm03254b4 256mb synchronous dram - die revision a ec update (-10) ?ibm corporation. all rights reserved. use is further subject to the provisions at the end of this document. page 6 of 68 29l0000.e36980a 7/99 block diagram - planar devices dq 0 dq x data input/output buffers cke buffer clk buffer cke clk cs ras cas dqm we command decoder mode register counter column address counter refresh a1 a2 a3 a4 a5 a6 a7 a10 a8 a11 sense amplifiers memory bank b cell array row decoder address buffers (15) column decoder sense amplifiers memory bank d cell array row decoder column decoder sense amplifiers memory bank a cell array row decoder column decoder sense amplifiers memory bank c cell array row decoder column decoder data control circuitry bs1 bs0 control signal generator cell array, per bank, for 16mb x 4 dq: 8192 row x 2048 col x 4 dq (dq0-dq3). cell array, per bank, for 8mb x 8 dq: 8192 row x 1024 col x 8 dq (dq0-dq7). cell array, per bank, for 4mb x 16 dq: 8192 row x 512 col x 16 dq (dq0-dq15). a12 a0 a9
ibm0325404 ibm0325804 ibm0325164 ibm03254b4 ec update (-10) 256mb synchronous dram - die revision a 29l0000.e36980a 7/99 ?ibm corporation. all rights reserved. use is further subject to the provisions at the end of this document. page 7 of 68 block diagram - 32mbit x 4 i/o x 4 bank (2-high) dq1 dq2 dq0 dq3 cke1 clk a12-a0 ras bs0, bs1 cas we dqm 16mb x 4 i/o x 4 bank cs0 cs1 cke0
ibm0325804 ibm0325404 ibm0325164 ibm03254b4 256mb synchronous dram - die revision a ec update (-10) ?ibm corporation. all rights reserved. use is further subject to the provisions at the end of this document. page 8 of 68 29l0000.e36980a 7/99 power on and initialization the default power-on state of the mode register is supplier specific and may be undefined. the following power on and initialization sequence guarantees the device is preconditioned to each users specific needs. like a conventional dram, the synchronous dram must be powered up and initialized in a predefined man- ner. during power on, all v dd and v ddq pins must be built up simultaneously to the specified voltage when the input signals are held in the nop state. the power-on voltage must not exceed v dd +0.3v on any of the input pins or v dd supplies. the clk signal must be started at the same time. after power on, an initial pause of 200 m s is required followed by a precharge of all banks using the precharge command. to prevent data contention on the dq bus during power on, it is required that the dqm and cke pins be held high during the initial pause period. once all banks have been precharged, the mode register set command must be issued to initialize the mode register. a minimum of two auto refresh cycles (cbr) are also required. these may be done before or after programming the mode register. failure to follow these steps may lead to unpredictable start-up modes. programming the mode register for application flexibility, cas latency, burst length, burst sequence, and operation type are user-defined variables and must be programmed into the sdram mode register with a single mode register set com- mand. any content of the mode register can be altered by re-executing the mode register set command. if the user chooses to modify only a subset of the mode register variables, all four variables must be redefined when the mode register set command is issued. after initial power up, the mode register set command must be issued before read or write cycles may begin. all banks must be in a precharged state and cke must be high at least one cycle before the mode register set command can be issued. the mode register set command is activated by the low signals of ras, cas, cs and we at the positive edge of the clock. the address input data during this cycle defines the parameters to be set as shown in the mode register operation table. a new command may be issued follow- ing the mode register set command once a delay equal to t rsc has elapsed. cas latency the cas latency is a parameter that is used to define the delay from when a read command is registered on a rising clock edge to when the data from that read command becomes available at the outputs. the cas latency is expressed in terms of clock cycles and can have a value of 2 or 3 cycles. the value of the cas latency is determined by the speed grade of the device and the clock frequency that is used in the application. a table showing the relationship between the cas latency, speed grade, and clock frequency appears in the electrical characteristics section of this document. once the appropriate cas latency has been selected it must be programmed into the mode register after power up; for an explanation of this procedure see pro- gramming the mode register in the previous section.
ibm0325404 ibm0325804 ibm0325164 ibm03254b4 ec update (-10) 256mb synchronous dram - die revision a 29l0000.e36980a 7/99 ?ibm corporation. all rights reserved. use is further subject to the provisions at the end of this document. page 9 of 68 mode register operation (address input for mode set) bt burst length cas latency cas latency m6 m5 m4 latency 0 0 0 reserved 0 0 1 reserved 010 2 011 3 1 0 0 reserved 1 0 1 reserved 1 1 0 reserved 1 1 1 reserved burst length m2 m1 m0 length sequential interleave 000 1 1 001 2 2 010 4 4 011 8 8 1 0 0 reserved reserved 1 0 1 reserved reserved 1 1 0 reserved reserved 1 1 1 reserved reserved burst type m3 type 0 sequential 1 interleave operation mode mbs1 mbs0 m12 m11 m10 m9 m8 m7 mode 0 0 0 0 0 0 0 0 normal 00000100 multiple burst with single write operation mode mode register (mx) address bus (ax) bs1 bs0 a12 a11 a10 a9 a8 a7 a6 a5 a4 a3 a2 a1 a0
ibm0325804 ibm0325404 ibm0325164 ibm03254b4 256mb synchronous dram - die revision a ec update (-10) ?ibm corporation. all rights reserved. use is further subject to the provisions at the end of this document. page 10 of 68 29l0000.e36980a 7/99 burst mode operation burst mode operation is used to provide a constant flow of data to memory locations (write cycle), or from memory locations (read cycle). there are three parameters that define how the burst mode will operate. these parameters include burst sequence, burst length, and operation mode. the burst sequence and burst length are programmable, and are determined by address bits a0 - a3 during the mode register set com- mand. operation mode is also programmable and is set by address bits a7 - a12, bs0, and bs1. the burst type is used to define the order in which the burst data will be delivered or stored to the sdram. two types of burst sequences are supported: sequential and interleaved. see the table below. the burst length controls the number of bits that will be output after a read command, or the number of bits to be input after a write command. the burst length can be programmed to have values of 1, 2, 4, or 8. burst operation mode can be normal operation or multiple burst with single write operation. normal operation implies that the device will perform burst operations on both read and write cycles until the desired burst length is satisfied. multiple burst with single write operation was added to support write through cache oper- ation. here, the programmed burst length only applies to read cycles. all write cycles are single write opera- tions when this mode is selected. burst length and sequence burst length starting address (a2 a1 a0) sequential addressing (decimal) interleave addressing (decimal) 2 x x 0 0, 1 0, 1 x x 1 1, 0 1, 0 4 x 0 0 0, 1, 2, 3 0, 1, 2, 3 x 0 1 1, 2, 3, 0 1, 0, 3, 2 x 1 0 2, 3, 0, 1 2, 3, 0, 1 x 1 1 3, 0, 1, 2 3, 2, 1, 0 8 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
ibm0325404 ibm0325804 ibm0325164 ibm03254b4 ec update (-10) 256mb synchronous dram - die revision a 29l0000.e36980a 7/99 ?ibm corporation. all rights reserved. use is further subject to the provisions at the end of this document. page 11 of 68 bank activate command in relation to the operation of a fast page mode dram, the bank activate command corresponds to a falling ras signal. the bank activate command is issued by holding cas and we high with cs and ras low at the rising edge of the clock. the bank select address bs0, bs1 is used to select the desired bank. the row address a0 - a12 is used to determine which row to activate in the selected bank. activation of banks within both decks of a 2-high stacked device is allowed. the bank activate command must be applied before any read or write operation can be executed. the delay from when the bank activate command is applied to when the first read or write operation can begin must meet or exceed the ras to cas delay time (t rcd ). once a bank has been activated it must be pre- charged before another bank activate command can be applied to the same bank. the minimum time interval between successive bank activate commands to the same bank is determined by the ras cycle time of the device (t rc ). the minimum time interval between interleaved bank activate commands (bank a to bank b and vice versa) is the bank to bank delay time (t rrd ). the maximum time that each bank can be held active is specified as t ras (max) . bank select the bank select inputs, bs0 and bs1, determine the bank to be used during a bank activate, precharge, read, or write operation. bank activate command cycle bank selection bits bs0 bs1 bank 0 0 bank 0 1 0 bank 1 0 1 bank 2 1 1 bank 3 address clk t0 t2 t1 t3 tn tn+1 tn+2 tn+3 command nop nop nop nop bank a row addr. bank a activate write a with auto bank a col. addr. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . bank b activate bank a row addr. bank a activate ras - cas delay (t rcd ) : h or l ras cycle time (t rc ) precharge ras - ras delay time (t rrd ) bank b row addr. ( cas latency = 3, t rcd = 3)
ibm0325804 ibm0325404 ibm0325164 ibm03254b4 256mb synchronous dram - die revision a ec update (-10) ?ibm corporation. all rights reserved. use is further subject to the provisions at the end of this document. page 12 of 68 29l0000.e36980a 7/99 read and write access modes after a bank has been activated, a read or write cycle can be executed. this is accomplished by setting ras high and cas low at the clocks rising edge after the necessary ras to cas delay (t rcd ). we must also be defined at this time to determine whether the access cycle is a read operation ( we high) or a write operation ( we low). the address inputs determine the starting column address. the sdram provides a wide variety of fast access modes. a single read or write command will initiate a serial read or write operation on successive clock cycles up to 133 mhz. the number of serial data bits for each access is equal to the burst length, which is programmed into the mode register. similar to page mode of conventional drams, a read or write cycle cannot begin until the sense amplifiers latch the selected row address information. the refresh period (t ref ) is what limits the number of random col- umn accesses to an activated bank. a new burst access can be done even before the previous burst ends. the ability to interrupt a burst operation at every clock cycle is supported; this is referred to as the 1-n rule. when the previous burst is interrupted by another read or write command, the remaining addresses are overridden by the new address. precharging an active bank after each read or write operation is not necessary providing the same row is to be accessed again. to perform a read or write cycle to a different row within an activated bank, the bank must be precharged and a new bank activate command must be issued. when more than one bank is activated, interleaved (ping pong) bank read or write operations are possible. by using the programmed burst length and alternating the access and precharge operations between multiple banks, fast and seamless data access operation among many different pages can be realized. when multiple banks are activated, column-to-col- umn interleave operation can be done between different pages. finally, read or write commands can be issued to the same bank or between active banks on every clock cycle. burst read command the burst read command is initiated by having cs and cas low while holding ras and we high at the rising edge of the clock. the address inputs determine the starting column address for the burst, the mode register sets the type of burst (sequential or interleave) and the burst length (1, 2, 4, 8). the delay from the start of the command to when the data from the first cell appears on the outputs is equal to the value of the cas latency that is set in the mode register. burst read operation command read a nop nop nop nop nop nop nop dout a 0 cas latency = 2 t ck3 , dqs cas latency = 3 dout a 1 dout a 2 dout a 3 nop clk t0 t2 t1 t3 t4 t5 t6 t7 t8 t ck2 , dqs dout a 0 dout a 1 dout a 2 dout a 3 (burst length = 4, cas latency = 2, 3)
ibm0325404 ibm0325804 ibm0325164 ibm03254b4 ec update (-10) 256mb synchronous dram - die revision a 29l0000.e36980a 7/99 ?ibm corporation. all rights reserved. use is further subject to the provisions at the end of this document. page 13 of 68 read interrupted by a read a burst read may be interrupted before completion of the burst by another read command, with the only restriction being that the interval that separates the commands must be at least one clock cycle. when the previous burst is interrupted, the remaining addresses are overridden by the new address with the full burst length. the data from the first read command continues to appear on the outputs until the cas latency from the interrupting read command is satisfied; at this point the data from the interrupting read command appears. read interrupted by a read command read a read b nop nop nop nop nop nop t ck2 , dqs cas latency = 2 t ck3 , dqs cas latency = 3 nop clk t0 t2 t1 t3 t4 t5 t6 t7 t8 dout b 0 dout b 1 dout b 2 dout b 3 dout a 0 dout b 0 dout b 1 dout b 2 dout b 3 dout a 0 (burst length = 4, cas latency = 2, 3)
ibm0325804 ibm0325404 ibm0325164 ibm03254b4 256mb synchronous dram - die revision a ec update (-10) ?ibm corporation. all rights reserved. use is further subject to the provisions at the end of this document. page 14 of 68 29l0000.e36980a 7/99 read interrupted by a write to interrupt a burst read with a write command, dqm may be needed to place the dqs (output drivers) in a high impedance state to avoid data contention on the dq bus. if a read command will issue data on the first or second clocks cycles of the write operation, dqm is needed to ensure the dqs are tri-stated. after that point the write command will have control of the dq bus. minimum read to write interval command nop nop read a write a nop nop nop dqm din a 0 din a 1 din a 2 din a 3 : h or l din a 0 din a 1 din a 2 din a 3 t ck2 , dqs cas latency = 2 t ck3 , dqs cas latency = 3 clk t0 t2 t1 t3 t4 t5 t6 t7 t8 nop nop dqm high for cas latency = 2 only. required to mask first bit of read data. (burst length = 4, cas latency = 2, 3)
ibm0325404 ibm0325804 ibm0325164 ibm03254b4 ec update (-10) 256mb synchronous dram - die revision a 29l0000.e36980a 7/99 ?ibm corporation. all rights reserved. use is further subject to the provisions at the end of this document. page 15 of 68 non-minimum read to write interval command nop nop read a write a nop nop nop dqm din a 0 din a 1 din a 2 din a 3 : dqm high for cas latency = 2 din a 0 din a 1 din a 2 din a 3 t ck2 , dqs cas latency = 2 t ck3 , dqs cas latency = 3 clk t0 t2 t1 t3 t4 t5 t6 t7 t8 nop nop : dqm high for cas latency = 3 cl=2: dqm needed to mask first, second bit of read data. cl=3: dqm needed to mask first bit of read data. (burst length = 4, cas latency = 2, 3)
ibm0325804 ibm0325404 ibm0325164 ibm03254b4 256mb synchronous dram - die revision a ec update (-10) ?ibm corporation. all rights reserved. use is further subject to the provisions at the end of this document. page 16 of 68 29l0000.e36980a 7/99 burst write command the burst write command is initiated by having cs, cas, and we low while holding ras high at the rising edge of the clock. the address inputs determine the starting column address. there is no cas latency required for burst write cycles. data for the first burst write cycle must be applied on the dq pins on the same clock cycle that the write command is issued. the remaining data inputs must be supplied on each subsequent rising clock edge until the burst length is completed. when the burst has finished, any additional data supplied to the dq pins will be ignored. write interrupted by a write a burst write may be interrupted before completion of the burst by another write command. when the previ- ous burst is interrupted, the remaining addresses are overridden by the new address and data will be written into the device until the programmed burst length is satisfied. burst write operation write interrupted by a write command nop write a nop nop nop nop nop nop dqs din a 0 din a 1 din a 2 din a 3 nop clk t0 t2 t1 t3 t4 t5 t6 t7 t8 extra data is masked. the first data element and the write are registered on the same clock edge. dont care ( burst length = 4, cas latency = 2, 3) command nop write a write b nop nop nop nop nop dqs din a 0 din b 0 din b 1 din b 2 nop din b 3 clk t0 t2 t1 t3 t4 t5 t6 t7 t8 1 clk interval (burst length = 4, cas latency = 2, 3)
ibm0325404 ibm0325804 ibm0325164 ibm03254b4 ec update (-10) 256mb synchronous dram - die revision a 29l0000.e36980a 7/99 ?ibm corporation. all rights reserved. use is further subject to the provisions at the end of this document. page 17 of 68 write interrupted by a read a read command will interrupt a burst write operation on the same clock cycle that the read command is registered. the dqs must be in the high impedance state at least one cycle before the interrupting read data appears on the outputs to avoid data contention. when the read command is registered, any residual data from the burst write cycle will be ignored. data that is presented on the dq pins before the read command is initiated will actually be written to the memory. minimum write to read interval command nop write a read b nop nop nop nop nop nop t ck2 dqs cas latency = 2 din a 0 t ck2 , dqs cas latency = 3 din a 0 clk t0 t2 t1 t3 t4 t5 t6 t7 t8 input data for the write is masked. input data must be removed from the dqs at least one clock cycle before the read data appears on the outputs to avoid data contention. dont care dout b 0 dout b 1 dout b 2 dout b 3 dout b 0 dout b 1 dout b 2 dout b 3 dont care dont care (burst length = 4, cas latency = 2, 3)
ibm0325804 ibm0325404 ibm0325164 ibm03254b4 256mb synchronous dram - die revision a ec update (-10) ?ibm corporation. all rights reserved. use is further subject to the provisions at the end of this document. page 18 of 68 29l0000.e36980a 7/99 non-minimum write to read interval command write a read b nop nop nop nop nop nop din a 0 din a 0 clk t0 t2 t1 t3 t4 t5 t6 t7 t8 input data for the write is masked. input data must be removed from the dqs at least one clock cycle before the read data appears on the outputs to avoid data contention. dout b 0 dout b 1 dout b 2 dout b 3 dout b 0 dout b 1 dout b 2 dout b 3 dont care nop din a 1 din a 1 dont care dont care t ck2 , dqs cas latency=2 t ck3 , dqs cas latency=3 (burst length = 4, cas latency = 2, 3)
ibm0325404 ibm0325804 ibm0325164 ibm03254b4 ec update (-10) 256mb synchronous dram - die revision a 29l0000.e36980a 7/99 ?ibm corporation. all rights reserved. use is further subject to the provisions at the end of this document. page 19 of 68 auto precharge operation before a new row in an active bank can be opened, the active bank must be precharged using either the pre- charge command or the auto precharge function. when a read or a write command is given to the sdram, the cas timing accepts one extra address, column address a10, to allow the active bank to automatically begin precharge at the earliest possible moment during the burst read or write cycle. if a10 is low when the read or write command is issued, then normal read or write burst operation is executed and the bank remains active at the completion of the burst sequence. if a10 is high when the read or write command is issued, then the auto precharge function is engaged. during auto precharge, a read command will execute as normal with the exception that the active bank will begin to precharge before all burst read cycles have been completed. regardless of burst length, the precharge will begin ( cas latency -1) clock prior to the last data output. auto precharge can also be implemented during write commands. a read or write command without auto precharge can be terminated in the midst of a burst operation. how- ever, a read or write command with auto precharge cannot be interrupted by a command to the same bank. therefore use of a read, write, or precharge command to the same bank is prohibited during a read or write cycle with auto precharge until the entire burst operation is completed. once the precharge operation has started the bank cannot be reactivated until the precharge time (t rp ) has been satisfied. when using the auto precharge command, the interval between the bank activate command and the begin- ning of the internal precharge operation must satisfy t ras (min). if this interval does not satisfy t ras (min) then t rcd must be extended. burst read with auto precharge command nop nop nop nop read a auto precharge t rp clk t0 t2 t1 t3 t4 t5 t6 t7 t8 nop nop nop t rp begin auto precharge bank can be reactivated at completion of t rp . dout a 0 dout a 0 nop t rp is a function of the clock cycle time and t ck2 , dqs cas latency = 2 t ck3 , dqs cas latency = 3 speed sort (see clock frequency and latency). (burst length = 1, cas latency = 2, 3)
ibm0325804 ibm0325404 ibm0325164 ibm03254b4 256mb synchronous dram - die revision a ec update (-10) ?ibm corporation. all rights reserved. use is further subject to the provisions at the end of this document. page 20 of 68 29l0000.e36980a 7/99 although a read command with auto precharge cannot be interrupted by a command to the same bank, it can be interrupted by a read or write command to a different bank. if the interrupting command is issued before auto precharge begins then the precharge function will begin with the new command. burst read with auto precharge burst read with auto precharge command nop nop nop nop read a auto precharge t rp clk t0 t2 t1 t3 t4 t5 t6 t7 t8 nop nop nop t rp begin auto precharge bank can be reactivated at completion of t rp . dout a 0 dout a 0 nop dout a 1 dout a 1 t ck2 , dqs cas latency = 2 t ck3 , dqs cas latency = 3 t rp is a function of the clock cycle time and speed sort (see clock frequency and latency). (burst length = 2, cas latency = 2, 3) command nop nop nop nop read a auto precharge t rp clk t0 t2 t1 t3 t4 t5 t6 t7 t8 nop nop nop t rp begin auto precharge bank can be reactivated at completion of t rp . dout a 0 dout a 1 dout a 2 dout a 3 nop dout a 0 dout a 1 dout a 2 dout a 3 t ck2 , dqs cas latency = 2 t ck3 , dqs cas latency = 3 t rp is a function of the clock cycle time and speed sort (see clock frequency and latency). (burst length = 4, cas latency = 2, 3)
ibm0325404 ibm0325804 ibm0325164 ibm03254b4 ec update (-10) 256mb synchronous dram - die revision a 29l0000.e36980a 7/99 ?ibm corporation. all rights reserved. use is further subject to the provisions at the end of this document. page 21 of 68 if interrupting a read command with auto precharge with a write command, dqm must be used to avoid dq contention. burst read with auto precharge interrupted by read burst read with auto precharge interrupted by write command nop nop nop nop read a auto precharge t rp clk t0 t2 t1 t3 t4 t5 t6 t7 t8 nop nop t rp * begin auto precharge a dout a 0 dout a 1 nop dout a 0 dout a 1 dout b 0 dout b 1 read b dout b 2 dout b 3 dout b 0 dout b 1 dout b 2 dout b 3 bank can be reactivated at completion of t rp . t ck2 , dqs cas latency = 2 t ck3 , dqs cas latency = 3 t rp is a function of the clock cycle time and speed sort (see clock frequency and latency). (burst length = 4, cas latency = 2, 3) command nop nop nop read a auto precharge t rp clk t0 t2 t1 t3 t4 t5 t6 t7 t8 nop nop t ck2 , dqs cas latency = 2 dqm begin auto precharge a bank a can be reactivated at completion of t rp . nop dout a 0 din b 0 din b 1 write b din b 2 din b 3 nop dout b 4 (burst length = 8, cas latency = 2)
ibm0325804 ibm0325404 ibm0325164 ibm03254b4 256mb synchronous dram - die revision a ec update (-10) ?ibm corporation. all rights reserved. use is further subject to the provisions at the end of this document. page 22 of 68 29l0000.e36980a 7/99 if a10 is high when a write command is issued, the write with auto precharge function is initiated. the bank undergoing auto precharge cannot be reactivated until t dal , data-in to active delay, is satisfied. similar to the read command, a write command with auto precharge cannot be interrupted by a command to the same bank. it can be interrupted by a read or write command to a different bank, however. the inter- rupting command will terminate the write. the bank undergoing auto precharge cannot be reactivated until t dal is satisfied. burst write with auto precharge burst write with auto precharge interrupted by write din a 0 command nop nop nop write a auto precharge din a 1 t dal clk t0 t2 t1 t3 t4 t5 t6 t7 t8 din a 0 din a 1 t dal bank can be reactivated at completion of t dal . t ck2 , dqs cas latency = 2 t ck3 , dqs cas latency = 3 nop nop nop number of clocks required depends on clock frequency. see clock frequency and latency (burst length = 2, cas latency = 2, 3) nop nop table. begin auto precharge din a 0 command nop nop nop write a auto precharge din a 1 clk t0 t1 t2 t3 t4 t5 nop t ck3 , dqs cas latency = 3 write b din b 0 din b 1 din b 2 din b 3 t6 t7 nop nop t dal (burst length = 4, cas latency = 3) bank can be reactivated at completion of t dal . number of clocks required depends on clock frequency. see clock frequency and latency table.
ibm0325404 ibm0325804 ibm0325164 ibm03254b4 ec update (-10) 256mb synchronous dram - die revision a 29l0000.e36980a 7/99 ?ibm corporation. all rights reserved. use is further subject to the provisions at the end of this document. page 23 of 68 precharge command the precharge command is used to precharge or close a bank that has been activated. the precharge com- mand is triggered when cs, ras, and we are low and cas is high at the rising edge of the clock. the pre- charge command can be used to precharge each bank separately or all banks simultaneously. three address bitsa10, bs0, and bs1are used to define which bank(s) is to be precharged when the command is issued. for read cycles, the precharge command may be applied ( cas latency - 1) prior to the last data output. for write cycles, a delay must be satisfied from the start of the last burst write cycle until the precharge com- mand can be issued. this delay is known as t dpl , data-in to precharge delay. after the precharge command is issued, the precharged bank must be reactivated before a new read or write access can be executed. the delay between the precharge command and the activate command must be greater than or equal to the precharge time (t rp ). burst write with auto precharge interrupted by read bank selection for precharge by address bits a10 bank select precharged bank(s) low bs0, bs1 single bank defined by bs0, bs1 high dont care all banks din a 0 command nop nop nop write a auto precharge din a 1 t dal clk t0 t2 t1 t3 t4 t5 t6 t7 t8 nop nop nop t ck3 , dqs cas latency=3 read b din a 2 nop dout b 0 dout b 1 dout b 2 (burst length = 4, cas latency = 3) bank can be reactivated at completion of t dal . number of clocks required depends on clock frequency. see clock frequency and latency table.
ibm0325804 ibm0325404 ibm0325164 ibm03254b4 256mb synchronous dram - die revision a ec update (-10) ?ibm corporation. all rights reserved. use is further subject to the provisions at the end of this document. page 24 of 68 29l0000.e36980a 7/99 burst read followed by the precharge command burst write followed by the precharge command command read ax 0 nop nop nop precharge a nop nop nop t ck2 , dqs cas latency = 2 clk t0 t2 t1 t3 t4 t5 t6 t7 t8 dout ax 0 dout ax 1 dout ax 2 dout ax 3 nop t rp bank a can be reactivated at completion of t rp . (burst length = 4, cas latency = 2) command nop nop nop write ax 0 clk t0 t2 t3 t4 t5 t6 t7 t8 nop nop nop din ax 0 din ax 1 activate bank ax t ck2 , dqs cas latency = 2 t dpl t rp bank a can be reactivated at completion of t rp . precharge a t1 (burst length = 2, cas latency = 2)
ibm0325404 ibm0325804 ibm0325164 ibm03254b4 ec update (-10) 256mb synchronous dram - die revision a 29l0000.e36980a 7/99 ?ibm corporation. all rights reserved. use is further subject to the provisions at the end of this document. page 25 of 68 precharge termination the precharge command may be used to terminate either a burst read or write operation. when the pre- charge command is issued, the burst operation is terminated and bank precharge begins. for burst read operations, valid data will continue to appear on the data bus as a function of cas latency. burst read interrupted by precharge command read ax 0 nop nop nop nop nop nop nop clk t0 t2 t1 t3 t4 t5 t6 t7 t8 dout ax 0 dout ax 1 dout ax 2 dout ax 3 precharge a dout ax 0 dout ax 1 dout ax 2 dout ax 3 t rp t rp bank a can be reactivated at completion of t rp .c t ck2 , dqs cas latency = 2 t ck3 , dqs cas latency = 3 t rp is a function of the clock cycle time and speed sort (see clock frequency and latency). (burst length = 8, cas latency = 2, 3)
ibm0325804 ibm0325404 ibm0325164 ibm03254b4 256mb synchronous dram - die revision a ec update (-10) ?ibm corporation. all rights reserved. use is further subject to the provisions at the end of this document. page 26 of 68 29l0000.e36980a 7/99 burst write operations will be terminated by the precharge command. the last write data that will be properly stored in the device is that write data that is presented to the device a number of clock cycles prior to the pre- charge command equal to the data-in to precharge delay, t dpl . automatic refresh command ( cas before ras refresh) when cs, ras, and cas are held low with cke and we high at the rising edge of the clock, the chip enters the automatic refresh mode (cbr). all banks of the sdram must be precharged and idle for a minimum of the precharge time (t rp ) before the auto refresh command (cbr) can be applied. for a stacked device, both decks may be refreshed at the same time using automatic refresh mode. an address counter internal to the device provides the address during the refresh cycle. no control of the external address pins is required once this cycle has started. when the refresh cycle has completed, all banks of the sdram will be in the precharged (idle) state. a delay between the auto refresh command (cbr) and the next activate command or subsequent auto refresh command must be greater than or equal to the ras cycle time (t rc ). precharge termination of a burst write command nop nop nop write ax 0 clk t0 t2 t1 t3 t4 t5 t6 t7 t8 nop nop nop din ax 1 din ax 2 din ax 0 nop din ax 1 din ax 2 din ax 0 dqm t dpl t ck2 , dqs cas latency = 2 t ck3 , dqs cas latency = 3 t dpl precharge a (burst length = 8, cas latency =2, 3)
ibm0325404 ibm0325804 ibm0325164 ibm03254b4 ec update (-10) 256mb synchronous dram - die revision a 29l0000.e36980a 7/99 ?ibm corporation. all rights reserved. use is further subject to the provisions at the end of this document. page 27 of 68 self refresh command the sdram device has a built-in timer to accommodate self refresh operation. the self refresh command is defined by having cs, ras, cas, and cke held low with we high at the rising edge of the clock. all banks must be idle prior to issuing the self refresh command. once the command is registered, cke must be held low to keep the device in self refresh mode. when the sdram has entered self refresh mode all of the external control signals, except cke, are disabled. the clock is internally disabled during self refresh opera- tion to save power. the user may halt the external clock while the device is in self refresh mode; however, the clock must be restarted before the device can exit self refresh operation. once the clock is cycling, the device will exit self refresh operation after cke is returned high. a minimum delay time is required when the device exits self refresh operation and before the next command can be issued. this delay is equal to the ras cycle time (t rc ) plus the self refresh exit time (t srex ). when using self refresh, both decks of a stacked device may be refreshed at the same time. power down mode in order to reduce standby power consumption, two power down modes are available: precharge and active power down mode. to enter precharge power down mode, all banks must be precharged and the necessary precharge delay (t rp ) must occur before the sdram can enter the power down mode. if a bank is activated but not performing a read or write operation, active power down mode will be entered. (issuing a power down mode command when the device is performing a read or write operation causes the device to enter clock suspend mode. see the following section.) once the power down mode is initiated by holding cke low, all of the receiver circuits except cke are gated off. the power down mode does not perform any refresh operations; therefore the device cant remain in power down mode longer than the refresh period (t ref ) of the device. the power down mode is exited by bringing cke high. when cke goes high, a no operation command or device deselect command is required on the next rising clock edge. power down mode exit timing command nop command nop nop nop nop nop cke : h or l clk tm tm+2 tm+1 tm+3 tm+4 tm+5 tm+6 tm+7 tm+ 8 t ces (min) t ck
ibm0325804 ibm0325404 ibm0325164 ibm03254b4 256mb synchronous dram - die revision a ec update (-10) ?ibm corporation. all rights reserved. use is further subject to the provisions at the end of this document. page 28 of 68 29l0000.e36980a 7/99 data mask the sdram has a data mask function that can be used in conjunction with data read and write cycles. when the data mask is activated (dqm high) during a write cycle, the write operation is prohibited immediately (zero clock latency). if the data mask is activated during a read cycle, the data outputs are disabled and become high impedance after a two-clock delay, independent of cas latency. no operation command the no operation command should be used in cases when the sdram is in an idle or a wait state. the pur- pose of the no operation command is to prevent the sdram from registering any unwanted commands between operations. a no operation command is registered when cs is low with ras, cas, and we held high at the rising edge of the clock. a no operation command will not terminate a previous operation that is still executing, such as a burst read or write cycle. deselect command the deselect command performs the same function as a no operation command. deselect command occurs when cs is brought high, the ras, cas, and we signals become dont cares. data mask activated during a read cycle command nop read a nop nop nop nop nop nop nop dqm : h or l a two-clock delay before the dqs become hi-z dqs clk t0 t2 t1 t3 t4 t5 t6 t7 t8 dout a 0 dout a 1 (burst length = 4, cas latency = 2)
ibm0325404 ibm0325804 ibm0325164 ibm03254b4 ec update (-10) 256mb synchronous dram - die revision a 29l0000.e36980a 7/99 ?ibm corporation. all rights reserved. use is further subject to the provisions at the end of this document. page 29 of 68 clock suspend mode during normal access mode, cke is held high, enabling the clock. when cke is registered low while at least one of the banks is active, clock suspend mode is entered. the clock suspend mode deactivates the inter- nal clock and suspends or freezes any clocked operation that was currently being executed. there is a one- clock delay between the registration of cke low and the time at which the sdrams operation suspends. while in clock suspend mode, the sdram ignores any new commands that are issued. the clock suspend mode is exited by bringing cke high. there is a one-clock-cycle delay from when cke returns high to when clock suspend mode is exited. when the operation of the sdram is suspended during the execution of a burst read operation, the last valid data output onto the dq pins will be actively held valid until clock suspend mode is exited. if clock suspend mode is initiated during a burst write operation, then the input data is masked and ignored until the clock suspend mode is exited. clock suspend during a read cycle clock suspend during a write cycle clk t0 t2 t1 t3 t4 t5 t6 t7 t8 command nop read a nop nop nop nop cke dqs dout a 0 dout a 2 dout a 1 : h or l a one clock delay before suspend operation starts a one clock delay to exit the suspend command dout element at the dqs when the suspend operation starts is held valid (burst length = 4, cas latency = 2) clk t0 t2 t1 t3 t4 t5 t6 t7 t8 command nop write a nop nop nop nop cke dqs din a 2 din a 3 : h or l a one clock delay before suspend operation starts a one clock delay to exit the suspend command din is masked during the clock suspend period din a 1 din a 0 (burst length = 4, cas latency = 2)
ibm0325804 ibm0325404 ibm0325164 ibm03254b4 256mb synchronous dram - die revision a ec update (-10) ?ibm corporation. all rights reserved. use is further subject to the provisions at the end of this document. page 30 of 68 29l0000.e36980a 7/99 command truth table (see note 1) function device state cke cs ras cas we dqm bs0, bs1 a10 a12, a11, a9- a0 notes previous cycle current cycle mode register set idle h x l l l l x op code auto (cbr) refresh idle h h l l l h x x x x entry self refresh idle h l l l l h x x x x exit self refresh idle (self- refresh) lh hxxx xx xx lhhh single bank precharge see current state table hxllhlxbslx 2 precharge all banks see current state table hxllhlxxhx bank activate idle h x l l h h x bs row address 2 write active h x l h l l x bs l column 2 write with auto precharge active h x l h l l x bs h column 2 read active h x l h l h x bs l column 2 read with auto precharge active h x l h l h x bs h column 2 no operation any h x l h h h x x x x device deselect any h x h x x x x x x x clock suspend mode entry active h l x x x x x x x x 3 clock suspend mode exit active l h x x x x x x x x data write/output enable active h x x x x x l x x x 4 data mask/output disable active h x x x x x h x x x power down mode entry idle/active h l hxxx xx xx 5, 6 lhhh power down mode exit any (power down) lh hxxx xx xx 5, 6 lhhh 1. all of the sdram operations are defined by states of cs, we, ras, cas, and dqm at the positive rising edge of the clock. oper- ation of both decks of a stacked device at the same time is allowed, depending on the operation being performed on the other deck. refer to the current state truth table. 2. bank select (bs0, bs1): bs0, bs1 = 0,0 selects bank 0; bs0, bs1 = 1,0 selects bank 1; bs0, bs1 = 0,1 selects bank 2; bs0, bs1 = 1,1 selects bank 3. 3. during normal access mode, cke is held high and clk is enabled. when it is low, it freezes the internal clock and extends dat a read and write operations. one clock delay is required for mode entry and exit. 4. the dqm has two functions for the data dq read and write operations. during a read cycle, when dqm goes high at a clock tim- ing the data outputs are disabled and become high impedance after a two clock delay. dqm also provides a data mask function for write cycles. when it activates, the write operation at the clock is prohibited (zero clock latency). 5. all banks must be precharged before entering the power down mode. (if this command is issued during a burst operation, the device state will be clock suspend mode.) the power down mode does not perform any refresh operations; therefore the device cant remain in this mode longer than the refresh period (t ref ) of the device. one clock delay is required for mode entry and exit. 6. a no operation or device deselect command is required on the next clock edge following cke going high.
ibm0325404 ibm0325804 ibm0325164 ibm03254b4 ec update (-10) 256mb synchronous dram - die revision a 29l0000.e36980a 7/99 ?ibm corporation. all rights reserved. use is further subject to the provisions at the end of this document. page 31 of 68 clock enable (cke) truth table current state cke command action notes previous cycle current cycle cs ras cas we bs0,bs1 a12 - a0 self refresh h x x x x x x x invalid 1 l h h x x x x x exit self refresh with device deselect 2 l h l h h h x x exit self refresh with no operation 2 l h l h h l x x illegal 2 l h l h l x x x illegal 2 l h l l x x x x illegal 2 l l x x x x x x maintain self refresh power down h x x x x x x x invalid 1 l h h x x x x x power down mode exit, all banks idle 2 l h l x x x x x illegal 2 l l x x x x x x maintain power down mode all banks idle hhhxxx refer to the idle state section of the current state truth table 3 hhlhxx 3 hhllhx 3 h h l l l h x x cbr refresh h h l l l l op code mode register set 4 hlhxxx refer to the idle state section of the current state truth table 3 hllhxx 3 hlllhx 3 h l l l l h x x entry self refresh 4 h l l l l l op code mode register set l x x x x x x x power down 4 any state other than listed above h h xxxx x x refer to operations in the current state truth table h l x x x x x x begin clock suspend next cycle 5 l h x x x x x x exit clock suspend next cycle l l x x x x x x maintain clock suspend 1. for the given current state cke must be low in the previous cycle. 2. when cke has a low to high transition, the clock and other inputs are re-enabled asynchronously. the minimum setup time for cke (t ces ) must be satis?ed before any command other than exit is issued. when exiting power down mode, a nop command (or device deselect command) is required on the ?rst rising clock after cke goes high (see page 27). 3. the address inputs (a12 - a0, bs0, bs1) depend on the command that is issued. see the idle state section of the current state truth table for more information. 4. the power down mode, self refresh mode, and the mode register set can only be entered from the all banks idle state. 5. must be a legal command as de?ned in the current state truth table.
ibm0325804 ibm0325404 ibm0325164 ibm03254b4 256mb synchronous dram - die revision a ec update (-10) ?ibm corporation. all rights reserved. use is further subject to the provisions at the end of this document. page 32 of 68 29l0000.e36980a 7/99 current state truth table (part 1 of 4) (see note 1) current state command action notes cs ras cas we bs0,bs1 a12 - a0 description idle l l l l op code mode register set set the mode register 2 l l l h x x auto or self refresh start auto or self refresh 2, 3 l l h l bs x precharge no operation llhh bs row address bank activate activate the specified bank and row l h l l bs column write w/o precharge illegal 4 l h l h bs column read w/o precharge illegal 4 l h h h x x no operation no operation h x x x x x device deselect no operation or power down 5 row active l l l l op code mode register set illegal l l l h x x auto or self refresh illegal l l h l bs x precharge precharge 6 llhh bs row address bank activate illegal 4 l h l l bs column write start write; determine if auto precharge 7, 8 l h l h bs column read start read; determine if auto precharge 7, 8 l h h h x x no operation no operation h x x x x x device deselect no operation read l l l l op code mode register set illegal l l l h x x auto or self refresh illegal l l h l bs x precharge terminate burst; start the precharge llhh bs row address bank activate illegal 4 l h l l bs column write terminate burst; start the write cycle 8, 9 l h l h bs column read terminate burst; start a new read cycle 8, 9 l h h h x x no operation continue the burst h x x x x x device deselect continue the burst 1. cke is assumed to be active (high) in the previous cycle for all entries. the current state is the state of the bank that the com- mand is being applied to. 2. all banks must be idle; otherwise, it is an illegal action. 3. if cke is active (high) the sdram will start the auto (cbr) refresh operation; if cke is inactive (low) the self refresh mode is entered. 4. the current state refers to only one of the banks. if bs selects this bank then the action is illegal. if bs selects the bank not being referenced by the current state then the action may be legal depending on the state of that bank. 5. if cke is inactive (low) then the power down mode is entered; otherwise there is a no operation. 6. the minimum and maximum active time (t ras ) must be satis?ed. 7. the ras to cas delay (t rcd ) must occur before the command is given. 8. column address a10 is used to determine if the auto precharge function is activated. 9. the command must satisfy any bus contention, bus turn around, and/or write recovery requirements. 10. the command is illegal if the minimum bank to bank delay time (t rrd ) is not satis?ed.
ibm0325404 ibm0325804 ibm0325164 ibm03254b4 ec update (-10) 256mb synchronous dram - die revision a 29l0000.e36980a 7/99 ?ibm corporation. all rights reserved. use is further subject to the provisions at the end of this document. page 33 of 68 write l l l l op code mode register set illegal l l l h x x auto or self refresh illegal l l h l bs x precharge terminate burst; start the precharge llhh bs row address bank activate illegal 4 l h l l bs column write terminate burst; start a new write cycle 8, 9 lhlh bs column read terminate burst; start the read cycle 8, 9 l h h h x x no operation continue the burst h x x x x x device deselect continue the burst read with auto pre- charge l l l l op code mode register set illegal l l l h x x auto or self refresh illegal l l h l bs x precharge illegal 4 llhh bs row address bank activate illegal 4 l h l l bs column write illegal 4 lhlh bs column read illegal 4 l h h h x x no operation continue the burst h x x x x x device deselect continue the burst write with auto pre- charge l l l l op code mode register set illegal l l l h x x auto or self refresh illegal l l h l bs x precharge illegal 4 llhh bs row address bank activate illegal 4 l h l l bs column write illegal 4 lhlh bs column read illegal 4 l h h h x x no operation continue the burst h x x x x x device deselect continue the burst current state truth table (part 2 of 4) (see note 1) current state command action notes cs ras cas we bs0,bs1 a12 - a0 description 1. cke is assumed to be active (high) in the previous cycle for all entries. the current state is the state of the bank that the com- mand is being applied to. 2. all banks must be idle; otherwise, it is an illegal action. 3. if cke is active (high) the sdram will start the auto (cbr) refresh operation; if cke is inactive (low) the self refresh mode is entered. 4. the current state refers to only one of the banks. if bs selects this bank then the action is illegal. if bs selects the bank not being referenced by the current state then the action may be legal depending on the state of that bank. 5. if cke is inactive (low) then the power down mode is entered; otherwise there is a no operation. 6. the minimum and maximum active time (t ras ) must be satis?ed. 7. the ras to cas delay (t rcd ) must occur before the command is given. 8. column address a10 is used to determine if the auto precharge function is activated. 9. the command must satisfy any bus contention, bus turn around, and/or write recovery requirements. 10. the command is illegal if the minimum bank to bank delay time (t rrd ) is not satis?ed.
ibm0325804 ibm0325404 ibm0325164 ibm03254b4 256mb synchronous dram - die revision a ec update (-10) ?ibm corporation. all rights reserved. use is further subject to the provisions at the end of this document. page 34 of 68 29l0000.e36980a 7/99 precharging l l l l op code mode register set illegal l l l h x x auto or self refresh illegal l l h l bs x precharge no operation; bank(s) idle after t rp llhh bs row address bank activate illegal 4 l h l l bs column write illegal 4 l h l h bs column read illegal 4 l h h h x x no operation no operation; bank(s) idle after t rp h x x x x x device deselect no operation; bank(s) idle after t rp row activating l l l l op code mode register set illegal l l l h x x auto or self refresh illegal l l h l bs x precharge illegal 4 llhh bs row address bank activate illegal 4, 10 l h l l bs column write illegal 4 l h l h bs column read illegal 4 l h h h x x no operation no operation; row active after t rcd h x x x x x device deselect no operation; row active after t rcd write recovering l l l l op code mode register set illegal l l l h x x auto or self refresh illegal l l h l bs x precharge illegal 4 llhh bs row address bank activate illegal 4 l h l l bs column write start write; determine if auto precharge 9 l h l h bs column read start read; determine if auto precharge 9 l h h h x x no operation no operation; row active after t dpl h x x x x x device deselect no operation; row active after t dpl current state truth table (part 3 of 4) (see note 1) current state command action notes cs ras cas we bs0,bs1 a12 - a0 description 1. cke is assumed to be active (high) in the previous cycle for all entries. the current state is the state of the bank that the com- mand is being applied to. 2. all banks must be idle; otherwise, it is an illegal action. 3. if cke is active (high) the sdram will start the auto (cbr) refresh operation; if cke is inactive (low) the self refresh mode is entered. 4. the current state refers to only one of the banks. if bs selects this bank then the action is illegal. if bs selects the bank not being referenced by the current state then the action may be legal depending on the state of that bank. 5. if cke is inactive (low) then the power down mode is entered; otherwise there is a no operation. 6. the minimum and maximum active time (t ras ) must be satis?ed. 7. the ras to cas delay (t rcd ) must occur before the command is given. 8. column address a10 is used to determine if the auto precharge function is activated. 9. the command must satisfy any bus contention, bus turn around, and/or write recovery requirements. 10. the command is illegal if the minimum bank to bank delay time (t rrd ) is not satis?ed.
ibm0325404 ibm0325804 ibm0325164 ibm03254b4 ec update (-10) 256mb synchronous dram - die revision a 29l0000.e36980a 7/99 ?ibm corporation. all rights reserved. use is further subject to the provisions at the end of this document. page 35 of 68 write recovering with auto precharge l l l l op code mode register set illegal l l l h x x auto or self refresh illegal l l h l bs x precharge illegal 4 llhh bs row address bank activate illegal 4 l h l l bs column write illegal 4, 9 lhlh bs column read illegal 4, 9 l h h h x x no operation no operation; precharge after t dpl h x x x x x device deselect no operation; precharge after t dpl refreshing l l l l op code mode register set illegal l l l h x x auto or self refresh illegal l l h l bs x precharge illegal llhh bs row address bank activate illegal l h l l bs column write illegal lhlh bs column read illegal l h h h x x no operation no operation; idle after t rc h x x x x x device deselect no operation; idle after t rc mode register accessing l l l l op code mode register set illegal l l l h x x auto or self refresh illegal l l h l bs x precharge illegal llhh bs row address bank activate illegal l h l l bs column write illegal lhlh bs column read illegal l h h h x x no operation no operation; idle after two clock cycles h x x x x x device deselect no operation; idle after two clock cycles current state truth table (part 4 of 4) (see note 1) current state command action notes cs ras cas we bs0,bs1 a12 - a0 description 1. cke is assumed to be active (high) in the previous cycle for all entries. the current state is the state of the bank that the com- mand is being applied to. 2. all banks must be idle; otherwise, it is an illegal action. 3. if cke is active (high) the sdram will start the auto (cbr) refresh operation; if cke is inactive (low) the self refresh mode is entered. 4. the current state refers to only one of the banks. if bs selects this bank then the action is illegal. if bs selects the bank not being referenced by the current state then the action may be legal depending on the state of that bank. 5. if cke is inactive (low) then the power down mode is entered; otherwise there is a no operation. 6. the minimum and maximum active time (t ras ) must be satis?ed. 7. the ras to cas delay (t rcd ) must occur before the command is given. 8. column address a10 is used to determine if the auto precharge function is activated. 9. the command must satisfy any bus contention, bus turn around, and/or write recovery requirements. 10. the command is illegal if the minimum bank to bank delay time (t rrd ) is not satis?ed.
ibm0325804 ibm0325404 ibm0325164 ibm03254b4 256mb synchronous dram - die revision a ec update (-10) ?ibm corporation. all rights reserved. use is further subject to the provisions at the end of this document. page 36 of 68 29l0000.e36980a 7/99 absolute maximum ratings symbol parameter rating units notes vdd power supply voltage -0.3 to +4.6 v 1 vddq power supply voltage for output -0.3 to +4.6 v 1 v in input voltage -0.3 to vdd+0.3 v 1 v out output voltage -0.3 to vdd+0.3 v 1 t a operating temperature (ambient) 0 to +70 c 1 t stg storage temperature -55 to +125 c 1 p d power dissipation 1.0 w 1 i out short circuit output current 50 ma 1 1. 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 operati onal sections of this specification is not implied. exposure to absolute maximum rating conditions for extended periods may affect r eli- ability. recommended dc operating conditions (t a = 0 to 70 c) symbol parameter rating units notes min. typ. max. vdd supply voltage 3.0 3.3 3.6 v 1 vddq supply voltage for output 3.0 3.3 3.6 v 1 v ih input high voltage 2.0 vdd + 0.3 v 1, 2 v il input low voltage -0.3 0.8 v 1, 3 1. all voltages referenced to v ss and vssq. 2. v ih (max) = vdd/vddq + 1.2v for pulse width 5ns . 3. v il (min) = vss/vssq - 1.2v for pulse width 5ns . capacitance (t a = 25 c, f = 1mhz, v dd = 3.3v 0.3v) symbol parameter min. typ. max. units notes c i input capacitance (a0-a12, bs0, bs1, cs, ras, cas, we, cke, dqm) 2.5 3.4 3.8 pf 1 input capacitance (clk) 2.5 3.2 3.5 pf 1 c o output capacitance (dq0 - dq15) 4.0 4.8 6.5 pf 1 1. multiply given planar values by 2 for 2-high stacked device (except cs and cke).
ibm0325404 ibm0325804 ibm0325164 ibm03254b4 ec update (-10) 256mb synchronous dram - die revision a 29l0000.e36980a 7/99 ?ibm corporation. all rights reserved. use is further subject to the provisions at the end of this document. page 37 of 68 dc electrical characteristics (t a = 0 to +70 c, v dd = 3.3v 0.3v) symbol parameter min. max. units notes i i(l) input leakage current, any input (0.0v v in vdd), all other pins not under test = 0v -1 +1 m a 1 i o(l) output leakage current (d out is disabled, 0.0v v out vddq) -1 +1 m a 1 v oh output level (lvttl) output h level voltage (i out = -2.0ma) 2.4 v v ol output level (lvttl) output l level voltage (i out = +2.0ma) 0.4 v 1. multiply given planar values by 2 for 2-high stacked device. dc output load circuit output 1200 w 50pf 3.3 v 870 w v oh (dc) = 2.4v, i oh = -2ma v ol (dc) = 0.4v, i ol = 2ma
ibm0325804 ibm0325404 ibm0325164 ibm03254b4 256mb synchronous dram - die revision a ec update (-10) ?ibm corporation. all rights reserved. use is further subject to the provisions at the end of this document. page 38 of 68 29l0000.e36980a 7/99 operating, standby and refresh currents (t a = 0 to +70 c, v dd = 3.3v 0.3v) parameter symbol test condition speed units notes -75a -260 -360 -10 operating current i cc1 1 bank operation, t rc = t rc (min), t ck = min, active precharge command cycling without burst operation 120 115 115 90 ma 1, 2, 3 precharge standby current in power down mode i cc2p cke v il (max), t ck = min, cs =v ih (min) 2222ma 1 i cc2ps cke v il (max), t ck = infinity, cs =v ih (min) 2222ma 1 precharge standby current in non-power down mode i cc2n cke 3 v ih (min), t ck = min, cs =v ih (min) 30 20 20 20 ma 1, 4 i cc2ns cke 3 v ih (min), t ck = infinity 6666ma 1, 7 no operating current (active state: 4 bank) i cc3n cke 3 v ih (min), t ck = min, cs = v ih (min) 60 45 45 55 ma 1, 5 i cc3p cke v il (max), t ck = min 6666ma 1, 6 operating current (burst mode) i cc4 t ck = min, read/ write command cycling, multiple banks active, gapless data, bl=4 155 115 115 115 ma 1, 3, 4 auto (cbr) refresh current i cc5 t ck = min, t rc = t rc (min) cbr command cycling 175 170 170 130 ma 1 self refresh current i cc6 cke 0.2v 3333ma 1 1. currents given are valid for a single device. the total current for a stacked device depends on the operation being performed on the other deck. 2. these parameters depend on the cycle rate and are measured with the cycle determined by the minimum value of t ck and t rc . input signals are changed up to three times during t rc (min). 3. the specified values are obtained with the output open. 4. input signals are changed once during t ck (min). 5. input signals are changed once during three clock cycles. 6. active standby current will be higher if clock suspend is entered during a burst read cycle (add 1ma per dq). 7. input signals are stable.
ibm0325404 ibm0325804 ibm0325164 ibm03254b4 ec update (-10) 256mb synchronous dram - die revision a 29l0000.e36980a 7/99 ?ibm corporation. all rights reserved. use is further subject to the provisions at the end of this document. page 39 of 68 ac characteristics (t a = 0 to +70 c, v dd = 3.3v 0.3v) 1. an initial pause of 200 m s, with dqm and cke held high, is required after power up. a precharge all banks command must be given followed by a minimum of two auto (cbr) refresh cycles before or after the mode register set operation. 2. the transition time is measured between v ih and v il (or between v il and v ih ). 3. in addition to meeting the transition rate speci?cation, the clock and cke must transit between v ih and v il (or between v il and v ih ) in a monotonic manner. 4. load circuit a: ac timing tests have v il = 0.4 v and v ih = 2.4 v with the timing referenced to the 1.40v crossover point 5. load circuit a: ac measurements assume t t =1.0 ns. 6. load circuit b: ac timing tests have v il = 0.8 v and v ih = 2.0 v with the timing referenced to the 1.40v crossover point 7. load circuit b: ac measurements assume t t =1.2 ns. ac diagrams clock and clock enable parameters symbol parameter -75a -260 -360 -10 units notes min. max. min. max. min. max. min. max. t ck3 clock cycle time, cas latency = 3 7.5 1000 10 1000 10 1000 10 1000 ns t ck2 clock cycle time, cas latency = 2 10 1000 15 1000 14 1000 ns t ac3 (a) clock access time, cas latency = 3 7 ns 1 t ac2 (a) clock access time, cas latency = 2 8 ns 1 t ac3 (b) clock access time, cas latency = 3 5.4 669ns 2 t ac2 (b) clock access time, cas latency = 2 699ns 2 t ckh clock high pulse width 2.5 3 33ns t ckl clock low pulse width 2.5 3 33ns t ces clock enable setup time 1.5 2 23ns t ceh clock enable hold time 0.8 1 11ns t sb power down mode entry time 0 7.5 0 10 0 10 0 10 ns t t transition time (rise and fall) 0.5 10 0.5 10 0.5 10 0.5 10 ns 1. access time is measured at 1.4v. see ac characteristics: notes: 1, 2, 3, 4, 5 and load circuit a. 2. access time is measured at 1.4v. see ac characteristics: notes: 1, 2, 3, 6, 7 and load circuit b. output input clock t oh t setup t hold t ac t lz 1.4v 1.4v 1.4v t t vtt=1.4v output 50 w 50pf z o = 50 w ac output load circuit (a) t ckh t ckl output 50pf z o = 50 w ac output load circuit (b) v il v ih
ibm0325804 ibm0325404 ibm0325164 ibm03254b4 256mb synchronous dram - die revision a ec update (-10) ?ibm corporation. all rights reserved. use is further subject to the provisions at the end of this document. page 40 of 68 29l0000.e36980a 7/99 common parameters symbol parameter -75a -260 -360 -10 units notes min. max. min. max. min. max. min. max. t cs command setup time 1.5 2 2 3 ns t ch command hold time 0.8 1 1 1 ns t as address and bank select setup time 1.5 2 2 3 ns t ah address and bank select hold time 0.8 1 1 1 ns t rcd ras to cas delay 20 20 20 28 ns 1 t rc bank cycle time 67.5 70 70 84 ns 1 t ras active command period 45 100000 50 100000 50 100000 56 100000 ns 1 t rp precharge time 20 20 20 14 ns 1 t rrd bank to bank delay time 15 20 20 20 ns 1 t ccd cas to cas delay time 1 1 1 1 clk 1. these parameters account for the number of clock cycle and depend on the operating frequency of the clock, as follows: the number of clock cycles = specified value of timing / clock period (count fractions as a whole number). mode register set cycle symbol parameter -75a -260 -360 -10 units notes min. max. min. max. min. max. min. max. t rsc mode register set cycle time 2 2 22clk 1 1. these parameters account for the number of clock cycle and depend on the operating frequency of the clock, as follows: the number of clock cycles = specified value of timing / clock period (count fractions as a whole number). read cycle symbol parameter -75a -260 -360 -10 units notes min. max. min. max. min. max. min. max. t oh data out hold time 2.5 2.5 3 ns 1 2.7333ns 2, 4 t lz data out to low impedance time 0 0 00ns t hz3 data out to high impedance time 3 5.4 3 6 3 6 3 7 ns 3 t hz2 data out to high impedance time 3 6 3 8 3 8 ns 3 t dqz dqm data out disable latency 2 2 22 clk 1. ac output load circuit a. 2. ac output load circuit b. 3. referenced to the time at which the output achieves the open circuit condition, not to output voltage levels. 4. data out hold time with no load must meet 1.8ns (-75a).
ibm0325404 ibm0325804 ibm0325164 ibm03254b4 ec update (-10) 256mb synchronous dram - die revision a 29l0000.e36980a 7/99 ?ibm corporation. all rights reserved. use is further subject to the provisions at the end of this document. page 41 of 68 refresh cycle symbol parameter -75a -260 -360 -10 units notes min. max. min. max. min. max. min. max. t ref refresh period 64 64 64 64 ms 1 t srex self refresh exit time 10 10 10 10 ns 1. 8192 auto refresh cycles. write cycle symbol parameter -75a -260 -360 -10 units min. max. min. max. min. max. min. max. t ds data in setup time 1.5 2 2 3 ns t dh data in hold time 0.8 1 1 1 ns t dpl data input to precharge 15 20 20 20 ns t dal3 data input to active, cl = 3 5 5 5 5 clk t dal2 data input to active, cl = 2 5 5 3 clk t dqw dqm write mask latency 0 0 0 0 clk clock frequency and latency symbol parameter -75a -260 -360 -10 units f ck clock frequency 133 100 100 100 66 100 71 mhz t ck clock cycle time 7.5 10 10 10 15 10 14 ns t aa cas latency 3323232 clk t rp precharge time 3222231 clk t rcd ras to cas delay 3222232 clk t rc bank cycle time 9 7 7 7 6 9 5 clk t ras minimum bank active time 6 5 5 5 4 6 4 clk t dpl data in to precharge 2 2 2 2 2 2 2 clk t dal data in to active/refresh 5 5 5 5 5 5 3 clk t rrd bank to bank delay time 2 2 2 2 2 2 2 clk t ccd cas to cas delay time 1 1 1 1 1 1 1 clk t wl write latency 0 0 0 0 0 0 0 clk t dqw dqm write mask latency 0 0 0 0 0 0 0 clk t dqz dqm data disable latency 2 2 2 2 2 2 2 clk t csl clock suspend latency 1 1 1 1 1 1 1 clk
ibm0325804 ibm0325404 ibm0325164 ibm03254b4 256mb synchronous dram - die revision a ec update (-10) ?ibm corporation. all rights reserved. use is further subject to the provisions at the end of this document. page 42 of 68 29l0000.e36980a 7/99 timing diagrams page ac parameters for write timing ................................................................................................. .............. 43 ac parameters for read timing (3/3/3), bl=4.................................................................................... ..... 44 ac parameters for read timing (2/2/2), bl=2.................................................................................... ..... 45 ac parameters for read timing (3/2/2), bl=2.................................................................................... ..... 46 ac parameters for read timing (3/3/3), bl=2.................................................................................... ..... 47 mode register set .............................................................................................................. ...................... 48 power on sequence and auto refresh (cbr)....................................................................................... .. 49 clock suspension / dqm during a burst read ..................................................................................... .. 50 clock suspension / dqm during a burst write .................................................................................... ... 51 power down mode and clock suspend .............................................................................................. ..... 52 auto refresh (cbr) ............................................................................................................. ..................... 53 self refresh (entry and exit) .................................................................................................. .................. 54 random row read (interleaving banks) with precharge, bl=8 .............................................................. 55 random row read (interleaving banks) with auto precharge, bl=8...................................................... 56 random row write (interleaving banks) with auto precharge, bl=8 ...................................................... 57 random row write (interleaving banks) with precharge, bl=8 .............................................................. 58 read and write cycle........................................................................................................... .................... 59 interleaved column read cycle .................................................................................................. ............. 60 auto precharge after a read burst, bl=4 ........................................................................................ ........ 61 auto precharge after a write burst, bl=4 ....................................................................................... ......... 62 burst read and single write operation.......................................................................................... .......... 63 cs function (only cs signal needs to be asserted at minimum rate)...................................................... 64
ibm0325404 ibm0325804 ibm0325164 ibm03254b4 ec update (-10) 256mb synchronous dram - die revision a 29l0000.e36980a 7/99 ?ibm corporation. all rights reserved. use is further subject to the provisions at the end of this document. page 43 of 68 ac parameters for write timing t0 t1 t2 t3 t4 t5 t6 t7 t8 t9 t10 t11 t12 t13 t14 t15 t16 t17 t18 t19 t20 t21 t dh t as t cs t ces t ck2 t ckl t ckh ax0 ax1 ax2 ax3 bx0 bx1 ay0 ay1 ay2 ay3 bx2 bx3 rax rax cax rbx rbx cbx ray ray ray activate command write with auto precharge command bank a activate command write with auto precharge command bank b activate command write command bank a precharge command activate command bank a activate command * bs0 = "l" bank c, d = idle clk cke cs ras cas we bs1* a10 a0-9, a11, a12 dqm dq bank b bank a bank a bank a bank b t rc t ch t ah raz rby rby raz t ceh t rp t rrd t dpl t ds t dal t22 t rcd ( cas latency = 2; burst length = 4) t dal
ibm0325804 ibm0325404 ibm0325164 ibm03254b4 256mb synchronous dram - die revision a ec update (-10) ?ibm corporation. all rights reserved. use is further subject to the provisions at the end of this document. page 44 of 68 29l0000.e36980a 7/99 ac parameters for read timing (3/3/3) t0 t1 t2 t3 t4 t5 t6 t7 t8 t9 t10 t11 t12 t13 t oh t rp t ras t rrd t rcd t ck3 ax0 ax1 bx0 bx1 rax rax cax rbx rbx cbx ray ray * bs0 = "l" bank c, d = idle activate command read with auto precharge command bank a activate command read with auto precharge command bank b activate command ax2 ax3 bx2 clk cke cs ras cas we bs1* a10 a0-9, a11, a12 dqm dq bank a bank b bank a t rc begin auto precharge bank a begin auto precharge bank b t ac3 t14 bx3 ( cas latency = 3; burst length = 4; t rcd , t rp = 3)
ibm0325404 ibm0325804 ibm0325164 ibm03254b4 ec update (-10) 256mb synchronous dram - die revision a 29l0000.e36980a 7/99 ?ibm corporation. all rights reserved. use is further subject to the provisions at the end of this document. page 45 of 68 ac parameters for read timing (2/2/2) t rp t rp t0 t1 t2 t3 t4 t5 t6 t7 t8 t9 t10 t11 t12 t hz t hz t oh t lz t ah t as t ch t cs t ces t rc t ras (min)** t ck2 t ckl t ckh ax0 ax1 bx0 bx1 rax rax cax rbx rbx cbx ray ray * bs0 = "l" bank c, d = idle activate command bank a read with auto precharge command bank a activate command bank b read with auto precharge command bank b activate command bank a **note: for -260, extend clk cke cs ras cas we bs1* a10 a0-9, a11, a12 dqm dq begin auto precharge bank b must satisfy t ras (min) t rcd 1 clk t rcd ** begin auto precharge bank a t ac2 t ceh t rrd t13 ( cas latency = 2; burst length = 2; t rcd , t rp = 2)
ibm0325804 ibm0325404 ibm0325164 ibm03254b4 256mb synchronous dram - die revision a ec update (-10) ?ibm corporation. all rights reserved. use is further subject to the provisions at the end of this document. page 46 of 68 29l0000.e36980a 7/99 ac parameters for read timing (3/2/2) t0 t1 t2 t3 t4 t5 t6 t7 t8 t9 t10 t11 t12 t13 t hz3 t oh t ah t as t ch t cs t ces t ck3 t rc t ckl t ckh ax0 ax1 bx0 bx1 rax rax cax rbx rbx ray ray * bs0 = "l" bank c, d = idle activate command read with auto precharge command bank a read with auto precharge command bank b activate command activate command bank b clk cke cs ras cas we bs1* a10 a0-9, a11, a12 dqm dq bank a bank a t ras (min)** t rcd ** t rrd begin auto precharge bank a t lz t ac3 cbx t14 **note: must satisfy t ras (min) extended t rcd one clock not required for bl 3 4 t rp t ceh begin auto precharge bank b t hz3 ( cas latency = 3; burst length = 2; t rcd , t rp = 2) t rp
ibm0325404 ibm0325804 ibm0325164 ibm03254b4 ec update (-10) 256mb synchronous dram - die revision a 29l0000.e36980a 7/99 ?ibm corporation. all rights reserved. use is further subject to the provisions at the end of this document. page 47 of 68 ac parameters for read timing (3/3/3) ray ray t0 t1 t2 t3 t4 t5 t6 t7 t8 t9 t10 t11 t12 t13 t14 t rp t rp t ck3 t rc ax0 ax1 bx0 bx1 rax rax cax rbx rbx activate command bank a read with auto precharge command bank a activate command bank b read with auto precharge command bank b activate command bank a *bs0 = "l" bank c, d = idle clk cke cs ras cas we bs1* a10 a0-9, a11, a12 dqm dq t rrd t ras (min)** t rcd ** t ceh t oh t ac3 bank a begin auto precharge begin auto precharge bank b **note: must satisfy t ras (min); extended t rcd 1 clock. extended t rcd not required for bl 3 4. t15 cbx ( cas latency = 3; burst length = 2; t rcd , t rp = 3)
ibm0325804 ibm0325404 ibm0325164 ibm03254b4 256mb synchronous dram - die revision a ec update (-10) ?ibm corporation. all rights reserved. use is further subject to the provisions at the end of this document. page 48 of 68 29l0000.e36980a 7/99 mode register set t0 t1 t2 t3 t4 t5 t6 t ck2 precharge command mode register set command any command high low address key clk cke cs ras cas we bs0, bs1 a10 a0-9, a11, a12 dqm dq t rp t rsc hi-z all banks t7 ( cas latency = 2)
ibm0325404 ibm0325804 ibm0325164 ibm03254b4 ec update (-10) 256mb synchronous dram - die revision a 29l0000.e36980a 7/99 ?ibm corporation. all rights reserved. use is further subject to the provisions at the end of this document. page 49 of 68 power on sequence and auto refresh (cbr) t0 t1 t2 t3 t4 t5 t6 t7 t8 t9 t10 t11 t12 t13 t14 t15 t16 t17 t18 t rc t ck precharge command all banks 1st auto refresh command 2nd auto refresh command inputs must be stable for 200 m sec mode register set command any command clk cke cs ras cas we bs a10 a0-9, a11, a12 dqm dq hi-z t rp t rc 2 clock min a minimum of 2 refresh cycles is required high level is required address key t19 t20
ibm0325804 ibm0325404 ibm0325164 ibm03254b4 256mb synchronous dram - die revision a ec update (-10) ?ibm corporation. all rights reserved. use is further subject to the provisions at the end of this document. page 50 of 68 29l0000.e36980a 7/99 clock suspension, dqm during burst read t0 t1 t2 t3 t4 t5 t6 t7 t8 t9 t10 t11 t12 t13 t14 t15 t16 t17 t18 t19 t20 t21 t hz t ck3 activate command bank a read command rax rax cax ax0 ax1 ax2 ax3 ax4 ax6 ax7 * bs0 = "l" bank c, d = idle clk cke cs ras cas we bs1* a10 a0-9, a11, a12 dqm dq bank a t ceh t ces clock suspend clock suspend dqm has no effect on data out since clk cycle t8 is suspended and the command bus is deactivated dqm will gate off ax5 since clk cycle t16 is not a suspended clock cycle clock suspend t22 1 cycle 2 cycles 3 cycles ( cas latency = 3; burst length = 8; t rcd = 3)
ibm0325404 ibm0325804 ibm0325164 ibm03254b4 ec update (-10) 256mb synchronous dram - die revision a 29l0000.e36980a 7/99 ?ibm corporation. all rights reserved. use is further subject to the provisions at the end of this document. page 51 of 68 clock suspension, dqm during burst write t0 t1 t2 t3 t4 t5 t6 t7 t8 t9 t10 t11 t12 t13 t14 t15 t16 t17 t18 t19 t20 t21 t ck3 clock rax rax cax dax0 dax1 dax2 dax5 * bs0 = "l" bank c, d = idle clock suspend clock suspend dax6 dax7 dax3 dqm is ignored since t17 is a suspended clock cycle clk cke cs ras cas we bs1* a10 a0-9, a11, a12 dqm dq 2 cycles suspend 1 cycle 3 cycles write command bank a dax4 is gated off with dqm since t14 is not a suspended clock cycle activate command bank a t22 ( cas latency = 3; burst length = 8; t rcd = 3)
ibm0325804 ibm0325404 ibm0325164 ibm03254b4 256mb synchronous dram - die revision a ec update (-10) ?ibm corporation. all rights reserved. use is further subject to the provisions at the end of this document. page 52 of 68 29l0000.e36980a 7/99 power down mode and clock suspend t0 t1 t2 t3 t4 t5 t6 t7 t8 t9 t10 t11 t12 t13 t14 t15 t16 t17 t18 t19 t20 t21 t22 t hz t sb t ck2 t sb activate command nop precharge command bank a rax cax ax0 ax1 * bs0 = "l" bank c, d = idle clock suspension start clock suspension end rax ax2 ax3 read command nop enter active exit active standby enter precharge standby exit precharge clk cke cs ras cas we bs1* a10 a0-9, a11, a12 dqm dq any t ces t ces t ces bank a standby bank a command standby valid t23 ( cas latency = 2; burst length = 4)
ibm0325404 ibm0325804 ibm0325164 ibm03254b4 ec update (-10) 256mb synchronous dram - die revision a 29l0000.e36980a 7/99 ?ibm corporation. all rights reserved. use is further subject to the provisions at the end of this document. page 53 of 68 auto refresh (cbr) t0 t1 t2 t3 t4 t5 t6 t7 t8 t9 t10 t11 t12 t13 t14 t15 t16 t rc t rc t ck2 precharge command auto refresh command auto refresh command high clk cke cs ras cas we bs a10 a0-9, a11, a12 dqm dq all banks t rp hi-z t17 ( cas latency = 2)
ibm0325804 ibm0325404 ibm0325164 ibm03254b4 256mb synchronous dram - die revision a ec update (-10) ?ibm corporation. all rights reserved. use is further subject to the provisions at the end of this document. page 54 of 68 29l0000.e36980a 7/99 self refresh t0 t1 t2 t3 t4 tm tm+1 tm+2 tm+3 tm+4 tm+5 tm+6 tm+7 tm+8 tm+9 tm+10tm+11tm+12tm+13tm+14 t ces t ces t sb t all banks must be idle self refresh self refresh hi-z any command low clk cke cs ras cas we bs a10 a 0-9, a11, a12 dqm dq tm+15 entry power down entry exit power down exit t rc clk must be re-established prior to cke returning high. (entry and exit) t srex
ibm0325404 ibm0325804 ibm0325164 ibm03254b4 ec update (-10) 256mb synchronous dram - die revision a 29l0000.e36980a 7/99 ?ibm corporation. all rights reserved. use is further subject to the provisions at the end of this document. page 55 of 68 random row read (interleaving banks) with precharge t0 t1 t2 t3 t4 t5 t6 t7 t8 t9 t10 t11 t12 t13 t14 t15 t16 t17 t18 t19 t20 t21 t22 t23 t ac3 t rcd t ck3 bx0 bx1 bx2 bx3 bx6 ax0 ax1 bx4 bx5 rbx rbx cbx rax rax cax rby cby activate command bank b read command bank b activate command bank a read command bank a precharge command bank b activate command bank b read command bank b precharge command bank a ax4 ax5 ax6 ax7 * bs0 = "l" bank c, d = idle rby clk cke cs ras cas we bs1* a10 a0-9, a11, a12 dqm dq t24 by1 by0 ( cas latency = 3; bl = 8; t rcd , t rp = 3)
ibm0325804 ibm0325404 ibm0325164 ibm03254b4 256mb synchronous dram - die revision a ec update (-10) ?ibm corporation. all rights reserved. use is further subject to the provisions at the end of this document. page 56 of 68 29l0000.e36980a 7/99 random row read (interleaving banks) with auto precharge t0 t1 t2 t3 t4 t5 t6 t7 t8 t9 t10 t11 t12 t13 t14 t15 t16 t17 t18 t19 t20 t rcd t ck3 bx0 bx1 bx2 bx3 bx6 bx7 ax0 bx4 bx5 rbx rbx cbx rax rax cax activate command bank b read with auto precharge command bank b activate command bank a read with auto precharge command bank a activate command bank b read with auto precharge command bank b ax4 ax5 ax6 ax7 * bs0 = "l" bank c, d = idle ax1 clk cke cs ras cas we bs1* a10 a0-9, a11, a12 dqm dq start auto precharge bank b t ac3 t21 rby rby start auto precharge bank a cby ( cas latency= 3; bl= 8; t rcd , t rp = 3)
ibm0325404 ibm0325804 ibm0325164 ibm03254b4 ec update (-10) 256mb synchronous dram - die revision a 29l0000.e36980a 7/99 ?ibm corporation. all rights reserved. use is further subject to the provisions at the end of this document. page 57 of 68 random row write (interleaving banks) with auto precharge t0 t1 t2 t3 t4 t5 t6 t7 t8 t9 t10 t11 t12 t13 t14 t15 t16 t17 t18 t19 t20 t21 t22 t rcd t ck3 dax0 dax1 dax6 dax7 dbx0 dax4 dax5 rax rax cax rbx rbx cbx ray cay activate command bank a write with auto precharge command bank a activate command bank b write with auto precharge command bank b activate command bank a write with auto precharge command bank a dbx4 dbx5 dbx6 * bs0 = "l" bank c, d = idle ray dbx1 dbx2 dbx3 dbx7 day0 day1 clk cke cs ras cas we bs1* a10 a0-9, a11, a12 dqm dq day2 t23 ( cas latency= 3; bl = 8; t rcd , t rp = 3) t dal t dal
ibm0325804 ibm0325404 ibm0325164 ibm03254b4 256mb synchronous dram - die revision a ec update (-10) ?ibm corporation. all rights reserved. use is further subject to the provisions at the end of this document. page 58 of 68 29l0000.e36980a 7/99 random row write (interleaving banks) with precharge t0 t1 t2 t3 t4 t5 t6 t7 t8 t9 t10 t11 t12 t13 t14 t15 t16 t17 t18 t19 t20 t21 t22 t23 t rp t rcd t ck3 rax rax cax rbx rbx cbx ray cay activate command bank a write command bank a activate command bank b write command bank b precharge command bank a activate command bank a write command bank a precharge command * bs0 = "l" ray dax0 dax1 dax6 dax7 dbx0 dax4 dax5 dbx4 dbx5 dbx6 dbx1 dbx2 dbx3 dbx7 day0 day1 day2 clk cke cs ras cas we bs1* a10 a0-9, a11, a12 dqm dq bank c, d = idle bank b day3 t24 ( cas latency = 3; bl = 8; t rcd , t rp = 3) t dpl
ibm0325404 ibm0325804 ibm0325164 ibm03254b4 ec update (-10) 256mb synchronous dram - die revision a 29l0000.e36980a 7/99 ?ibm corporation. all rights reserved. use is further subject to the provisions at the end of this document. page 59 of 68 read-write cycle t0 t1 t2 t3 t4 t5 t6 t7 t8 t9 t10 t11 t12 t13 t14 t15 t16 t17 t18 t ck3 t rax rax cax cay activate command bank a read command bank a write command precharge command bank a * bs0 = "l" bank c, d = idle ax2 ax3 ax0 ax1 day3 day4 day0 day1 high read data masked with two clock latency write data masked with zero clock latency clk cke cs ras cas we bs1* a10 a0-9, a11, a12 dqm dq bank a t19 ( cas latency = 3; burst length = 8; t rcd = 3)
ibm0325804 ibm0325404 ibm0325164 ibm03254b4 256mb synchronous dram - die revision a ec update (-10) ?ibm corporation. all rights reserved. use is further subject to the provisions at the end of this document. page 60 of 68 29l0000.e36980a 7/99 interleaved column read cycle t0 t1 t2 t3 t4 t5 t6 t7 t8 t9 t10 t11 t12 t13 t14 t15 t16 t17 t18 t19 t20 t21 t ac3 t ck3 ax0 ax1 ax2 bx1 by0 by1 ax3 bx0 rax rax rbx cbx cby cay activate command bank a read command bank a read command bank b read command bank b read with auto precharge command bank a read command bank b precharge command bank b ay0 ay1 ay2 ay3 * bs0 = "l" bank c, d = idle high rbx cax cbz bz0 bz1 low clk cke cs ras cas we bs1* a10 a 0-9, a11, a12 dqm dq activate command bank b t rcd start auto precharge bank a t22 ( cas latency = 3; burst length = 4; t rcd = 3)
ibm0325404 ibm0325804 ibm0325164 ibm03254b4 ec update (-10) 256mb synchronous dram - die revision a 29l0000.e36980a 7/99 ?ibm corporation. all rights reserved. use is further subject to the provisions at the end of this document. page 61 of 68 auto precharge after read burst t0 t1 t2 t3 t4 t5 t6 t7 t8 t9 t10 t11 t12 t13 t14 t15 t16 t17 t18 t19 t20 t21 t22 t23 t ck3 t ax0 ax1 ax2 bx1 bx2 bx3 ax3 bx0 rax rax rbx cbx cay rby activate command bank a read command bank a read with auto precharge command bank b activate command bank b read with auto precharge command read with auto precharge command bank a ay2 ay3 * bs0 = "l" bank c, d = idle rbx cax ay0 ay1 low rby cby by0 by1 by2 by3 clk cke cs ras cas we bs1* a10 a0-9, a11, a12 dqm dq bank b activate command bank b start auto precharge bank b start auto precharge bank a start auto precharge bank b t24 ( cas latency = 3; burst length = 4; t rcd = 3)
ibm0325804 ibm0325404 ibm0325164 ibm03254b4 256mb synchronous dram - die revision a ec update (-10) ?ibm corporation. all rights reserved. use is further subject to the provisions at the end of this document. page 62 of 68 29l0000.e36980a 7/99 auto precharge after write burst t0 t1 t2 t3 t4 t5 t6 t7 t8 t9 t10 t11 t12 t13 t14 t15 t16 t17 t18 t19 t20 t21 t22 t23 t ck2 t dbx0 dbx1 dbx2 day1 day2 day3 dbx3 day0 rax rax rbx cbx cay rby activate command bank a write command bank a activate command bank b write with auto precharge command bank b activate command bank b write with auto write with auto precharge command dby2 dby3 * bs0 = "l" bank c, d = idle rbx cax dby0 dby1 low rby cby daz1 daz2 raz raz caz dax0 dax1 dax2 dax3 daz0 daz3 activate command bank a high clk cke cs ras cas we bs1* a10 a0-9, a11, a12 dqm dq write with auto precharge command bank a bank b precharge command bank a t24 ( cas latency = 2; burst length = 4) t dal t dal t dal t dal
ibm0325404 ibm0325804 ibm0325164 ibm03254b4 ec update (-10) 256mb synchronous dram - die revision a 29l0000.e36980a 7/99 ?ibm corporation. all rights reserved. use is further subject to the provisions at the end of this document. page 63 of 68 burst read and single write operation t0 t1 t2 t3 t4 t5 t6 t7 t8 t9 t10 t11 t12 t13 t14 t15 t16 t17 t18 t19 t20 t21 t ck2 t av2 av3 daw0 rav rav caw cax activate command bank a read command bank a bank a single write command bank a upper byte masked read command bank a ay1 * bs0 = "l" bank c, d = idle cav ay0 cay daz0 caz av0 av1 ay3 single write command av2 av3 ay0 daz0 av0 av1 ay3 dax0 ay2 lower byte masked lower byte masked high upper byte masked clk cke cs ras cas we bs1* a10 a0-9, a11, a12 ldqm udqm dq0-7 dq8-15 bank a single write command t22 ( cas latency = 2; burst length = 4)
ibm0325804 ibm0325404 ibm0325164 ibm03254b4 256mb synchronous dram - die revision a ec update (-10) ?ibm corporation. all rights reserved. use is further subject to the provisions at the end of this document. page 64 of 68 29l0000.e36980a 7/99 cs function (only cs signal needs to be asserted at minimum rate) clk cke cs dq ras cas we a11(bs) dqm t2 t3 t4 t0 t1 t6 t7 t8 t9 t5 t11 t12 t13 t14 t10 t16 t17 t18 t19 t15 t22 t20 t21 hi-z a10 a0 - a9 t ck3 rax low rax cax cay read command bank a write command bank a activate command bank a precharge command bank a ax0 day0 day3 day2 day1 ax3 ax2 ax1 t rcd t dpl ( cas latency = 3; burst length = 4; t rcd /t rp = 3)
ibm0325404 ibm0325804 ibm0325164 ibm03254b4 ec update (-10) 256mb synchronous dram - die revision a 29l0000.e36980a 7/99 ?ibm corporation. all rights reserved. use is further subject to the provisions at the end of this document. page 65 of 68 package dimensions (400mil; 54 lead; thin small outline package) 0.80 basic 0.35 - 0.05 + 0.10 0.71ref detail a 0.10 seating plane detail a 0.5 0.1 0.05 min 1.20 max 0.25 basic gage plane lead #1 10.16 0.13 22.22 0.13 11.76 0.20
ibm0325804 ibm0325404 ibm0325164 ibm03254b4 256mb synchronous dram - die revision a ec update (-10) ?ibm corporation. all rights reserved. use is further subject to the provisions at the end of this document. page 66 of 68 29l0000.e36980a 7/99 package dimensions (400mil; 66 lead; 2 high stack; thin small outline j lead package) 0.75 min 3.20 max 9.90 0.40 0.65 basic lead #1 10.15 0.15 22.25 0.3 11.4 0.25 0.10 seating plane 0.3 - 0.04 + 0.10
ibm0325404 ibm0325804 ibm0325164 ibm03254b4 ec update (-10) 256mb synchronous dram - die revision a 29l0000.e36980a 7/99 ?ibm corporation. all rights reserved. use is further subject to the provisions at the end of this document. page 67 of 68 revision log revision location contents of modi?cation 8/24/98 -- initial release 1/7/99 page 1 change -260 to 135 mhz maximum, -360 to 100mhz maximum. also page 39 and page 41. remove -68, low power. page 5 update clock cycle for -260, -360. remove -68, low power. page 6 correct cell array information. page 9 update mode register figure. page 22-23 correct burst write with auto precharge / interrupt. page 24 correct burst read followed by a precharge command timing diagram. page 30 update bank designation for consistency. page 32 remove burst termination from current state truth table. page 38 update currents. page 39 correct number of cbrs required (note 1). page 39-page 41 update timings: -260 (t ck3, t setup, t hold, t rc, t ras, t rrd, t sb, t rsc, t dpl, t dal ); -360 (t ck3, t ras, t rrd, t sb, t rsc, t dpl, t dal ); -10 (t ck2, t rc, t ras, t rcd, t rp, t rsc, t dpl, t dal ) . remove -68. page 44-page 47, page 49, page 50, page 52, page 54, page 55, page 56, page 61, page 62 correct timing diagrams. page 65, 66 correct package dimensions. correct drawing of 2 high stack package. 2/11/99 page 1 add -75a. change -260 to 100 mhz maximum. page 5 add -75a. update clock cycle for -260. page 36 update capacitance table. page 38 update currents. page 39 - page 41 add -75a timings. update -260 timings: t ck3 , t setup , t hold , t rc , t ras , t rrd , t dpl . 3/19/99 page 11 update bank selection bits. page 40 update t rp , t rcd for -75a (22.5 to 20ns) page 41 update t dpl from 15 to 20ns (-260, -360), t dal2 from 4 to 5 clk (-360) 6/30/99 -- removed preliminary. 7/27/99 page 40, 41 update t rp (28ns to14ns), t dpl (14ns to 20ns), t dal2 (4clk to 3clk), for -10 sort
intern ational business machines corp.1999 copyright printed in the united states of america all rights reserved ibm and the ibm logo are registered trademarks of the ibm corporation. this document may contain preliminary information and is subject to change by ibm without notice. ibm assumes no responsibility or liability for any use of the information contained herein. nothing in this document shall operate as an express or implied lice nse or indemnity under the intellectual property rights of ibm or third parties. the products described in this document are not inten ded for use in implantation or other direct life support applications where malfunction may result in direct physical harm or injury to persons. no warranties of any kind, including, but not limited to, the implied warranties of merchantability or fitness for a particular purpose, are offered in this document . for more information contact your ibm microelectronics sales representative or visit us on world wide web at http://www.chips.ibm.com ibm microelectronics manufacturing is iso 9000 compliant. a

▲Up To Search▲

Price & Availability of IBM0325404CT3A-75A

	To Download IBM0325404CT3A-75A Datasheet File
If you can't view the Datasheet, Please click here to try to view without PDF Reader .