AS4LC4M16

DRAM D RAM Austin Semiconductor, Inc. 4 MEG x 16 DRAM Extended Data Out (EDO) DRAM FEATURES • Single +3.3V ±0.3V power supply. • Industry-standard x16 pinout, timing, functions, and package. • 12 row, 10 column addresses • High-performance CMOS silicon-gate process • All inputs, outputs and clocks are LVTTL-compatible • Extended Data-Out (EDO) PAGE MODE access • 4,096-cycle CAS\-BEFORE-RAS\ (CBR) REFRESH distributed across 64ms • Optional self refresh (S) for low-power data retention • Level 1 Moisture Sensitivity Rating, JEDEC J-STD-020 AS4LC4M16 PIN ASSIGNMENT (Top View) 50-Pin TSOP (DG) OPTIONS • Package(s) 50-pin TSOP (400-mil) • Timing 50ns access 60ns access • Refresh Rates Standard Refresh Self Refresh • Operating Temperature Ranges Military (-55°C to +125°C) Industrial (-40°C to +85°C) MARKINGS DG -5 -6 Configuration Refresh Row Address Column Addressing 4 Meg x 16 4K A0-A11 A0-A9 None S* XT IT NOTE: The \ symbol indicates signal is active LOW. *Contact factory for availability. Self refresh option available on IT version only. KEY TIMING PARAMETERS tRAC SPEED tRC -5 84ns 50ns -6 104ns 60ns tPC 20ns 25ns tAA 25ns 30ns tCAC 13ns 15ns tCAS 8ns 10ns For more products and information please visit our web site at www.austinsemiconductor.com AS4LC4M16 Rev. 1.1 6/05 Austin Semiconductor, Inc. reserves the right to change products or specifications without notice. 1 DRAM D RAM Austin Semiconductor, Inc. FUNCTIONAL BLOCK DIAGRAM AS4LC4M16 AS4LC4M16 Rev. 1.1 6/05 Austin Semiconductor, Inc. reserves the right to change products or specifications without notice. 2 DRAM D RAM Austin Semiconductor, Inc. GENERAL DESCRIPTION The 4 Meg x 16 DRAM is a high-speed CMOS, dynamic random-access memory device containing 67,108,864 bits and designed to operate from 3V to 3.6V. The device is functionally organized as 4,194,304 locations containing 16 bits each. The 4,194,304 memory locations are arranged in 4,096 rows by 1,024 columns. During READ or WRITE cycles, each location is uniquely addresses via the address bits: 12 row-address bits (A0 - A11) and 10 column-address bits (A0 - A9). In addition, both byte and word accesses are supported via the two CAS\ pins (CASL\ and CASH\). The CAS\ functionality and timing related to address and control functions (e.g., latching column addresses or selecting CBR REFRESH) is such that the internal CAS\ signal is determined by the first external CAS\ signal (CASL\ or CASH\) to transition LOW and the last to transition back HIGH. The CAS\ functionality and timing related to driving or latching data is such that each CAS\ signal independently controls the associated either DQ pins. AS4LC4M16 The row address is latched by the RAS\ signal, then the column address is latched by CAS\. This device provides EDO-PAGE-MODE operation, allowing for fast successive data operations (READ, WRITE or READ-MODIFY-WRITE) within a given row. The 4 Meg x 16 DRAM must be refreshed periodically in order to retain stored data. DRAM ACCESS Each location in the DRAM is uniquely addressable, as mentioned in the General Description. Use of both CAS\ signals resulted in a word access via the 16 I/O pins (DQ0 - DQ15). Using only one of the two signals results in a BYTE access cycle. CASL\ transitioning LOW selects an access cycle for the lower byte (DQ0 - DQ7), and CASH\ transitioning LOW selects an access cycle for the upper byte (DQ8-DQ15). General byte and word access timing is shown in Figures 1 and 2. FIGURE 1: WORD and BYTE WRITE Example AS4LC4M16 Rev. 1.1 6/05 Austin Semiconductor, Inc. reserves the right to change products or specifications without notice. 3 DRAM D RAM Austin Semiconductor, Inc. DRAM ACCESS (continued) A logic HIGH on WE\ dictates read mode, while a logic LOW on WE\ dictates write mode. During a WRITE cycle, data-in (D) is latched by the falling edge of WE or CAS\ (CASL\ or CASH\), whichever occurs last. An EARLY WRITE occurs when WE is taken LOW prior to either CAS\ falling. A LATE WRITE or READ-MODIFY-WRITE occurs when WE falls after CAS\ (CASL\ or CASH\) is taken LOW. During EARLY WRITE cycles, the data outputs (Q) will remain High-Z, regardless of the state of OE\. During LATE WRITE or READ-MODIFYWRITE cycles, OE\ must be taken HIGH to disable the data outputs prior to applying input data. If a LATE WRITE or READ-MODIFY-WRITE is attempted while keeping OE\ LOW, no write will occur, and the data outputs will drive read data from the accessed location. Additionally, both bytes are active. A CAS\ precharge must be satisfied prior to changing modes of operation between the upper and lower bytes. For example, an EARLY WRITE on one byte and a LATE WRITE on the other byte are AS4LC4M16 not allowed during the same cycle. However, an EARLY WRITE on one byte and a LATE WRITE on the other byte, after a CAS\ precharge has been satisfied, are permissible. EDO PAGE MODE DRAM READ cycles have traditionally turned the output buffers off (High-Z) with the rising edge of CAS\. If CAS\ went HIGH and OE\ was LOW (active), the output buffers would be disabled. The 64MB EDO DRAM offers an accelerated page mode cycle by eliminating output disable from CAS\ HIGH. This option is called EDO, and it allows CAS\ precharge time (tCP) to occur without the output data going invalid (see READ and EDO-PAGE-MODE READ waveforms). EDO operates like any DRAM READ or FAST-PAGEMODE READ, except data is held valid after CAS\ goes HIGH, as long as RAS\ and OE\ are held LOW and WE\ is held HIGH. OE\ can be brought LOW or HIGH while CAS\ and RAS\ are LOW, and the DQs will transition between valid data and HighZ. Using OE\, there are two methods to disable the outputs and FIGURE 2: WORD and BYTE READ Example AS4LC4M16 Rev. 1.1 6/05 Austin Semiconductor, Inc. reserves the right to change products or specifications without notice. 4 DRAM D RAM Austin Semiconductor, Inc. FIGURE 3: OE\ Control of DQs AS4LC4M16 FIGURE 4: WE\ Control of DQs AS4LC4M16 Rev. 1.1 6/05 Austin Semiconductor, Inc. reserves the right to change products or specifications without notice. 5 DRAM D RAM Austin Semiconductor, Inc. EDO PAGE MODE (Continued) two methods to disable the outputs and keep them disabled during the CAS\ HIGH time. The first method is to have OE\ HIGH when CAS\ transitions HIGH and keep OE\ HIGH for tOEHC thereafter. This will disable the DQs, and they will remain disabled (regardless of the state of OE\ after that point) until CAS\ falls again. The second method is to have OE\ LOW when CAS\ transitions HIGH and then bring OE\ HIGH for a minimum of tOEP anytime during the CAS\ HIGH period. This will disable the DQs, and they will remain disabled (regardless of the state of OE\ after that point) until CAS\ falls again (see Figure 3). During other cycles, the outputs are disabled at tOFF time after RAS\ and CAS\ are HIGH or at tWHZ after WE\ transitions LOW. The tOFF time is referenced from the rising edge of RAS\ or CAS\, whichever occurs last. WE\ can also perform the function of disabling the output drivers under certain conditions, as shown in Figure 4. EDO-PAGE-MODE operations are always initiated with a row address strobed in by the RAS\ signal, followed by a column address strobed in by CAS\, just like for single location accesses. However, subsequent column locations within the row may then be accessed at the page mode cycle time. This is accomplished by cycling CAS\ while holding RAS\ LOW and entering new column addresses with each CAS\ cycle. Returning RAS\ HIGH terminates the EDO-PAGE-MODE operation. AS4LC4M16 DRAM REFRESH The supply voltage must be maintained at the specified levels, and the refresh requirements must be met in order to retain stored data in the DRAM. The refresh requirements are met by refreshing all rows in the 4 Meg x 16 DRAM array at least once every 64ms* (4,096 rows). The recommended procedure is to execute 4,096 CBR REFRESH cycles, either uniformly spaced or grouped in bursts, every 64ms*. The DRAM refreshes one row for every CBR cycle. For this device, executing 4,096 CBR cycles will refresh the entire device. The CBR REFRESH will invoke the internal refresh counter for automatic RAS\ addressing. Alternatively, RAS\-ONLY REFRESH capability is inherently provided. However, with this method, only one row is refreshed on each cycle. JEDEC strongly recommends the use of CBR REFRESH for this device. An optional self refresh mode is also available on the “S” version. The self refresh feature is initiated by performing a CBR Refresh cycle and holding RAS\ low for the specified tRASS. The “S” option allows the user the choice of a fully static, low-power data retention mode or a dynamic refresh mode at the extended refresh period of 128ms, or 31.25µs per cycle, when using a distributed CBR refresh. This refresh rate can be applied during normal operation, as well as during a standby or battery backup mode. The self refresh mode is terminated by driving RAS\ HIGH for a minimum time of tRPS. This delay allows for the completion of any internal refresh cycles that may be in process at the time of the RAS\ LOW-to-HIGH transition. If the DRAM controller uses a distributed CBR refresh sequence, a burst refresh is not required upon exiting self refresh, however, if the controller is using RAS\ only or burst CBR refresh then a burst refresh using tRC (MIN) is required. NOTES: *64ms for IT version, 32ms for XT version. AS4LC4M16 Rev. 1.1 6/05 Austin Semiconductor, Inc. reserves the right to change products or specifications without notice. 6 DRAM D RAM Austin Semiconductor, Inc. ABSOLUTE MAXIMUM RATINGS* Voltage on VCC Relative to VSS .......................................-1V to +4.6V Voltage on NC, Inputs or I/O Pins Relative to VSS...................................................-1V to +4.6V Power Dissipation...........................................................................1W Operating temperature range, TA (ambient)..............-55°C to 125°C Storage temperature (plastic)......................................-55°C to 150°C AS4LC4M16 *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 operation section of this specification is not implied. Exposure to absolute maximum rating conditions for extended periods may affect reliability. DC ELECTRICAL CHARACTERISTICS AND OPERATING CONDITIONS1 (VCC = +3.3V ±0.3V) PARAMETERS SUPPLY VOLTAGE INPUT HIGH VOLTAGE: Valid Logic 1; All inputs, I/Os and any NC INPUT LOW VOLTAGE: Valid Logic 0; All inputs, I/Os and any NC INPUT LEAKAGE CURRENT: Any input at VIN (0V < VIN < VCC +0.3V); All other pins not under test = 0V OUTPUT LEAKAGE CURRENT: Any input at VOUT (0V < VOUT < VCC +0.3V); DQ is disabled and in High-Z state OUTPUT HIGH VOLTAGE: IOUT = -2mA OUTPUT LOW VOLTAGE: IOUT = 2mA SYM VCC VIH VIL II MIN 3 2 -0.3 MAX 3.6 VCC + 0.3 0.8 UNITS V V V 35 35 NOTES -2 2 µA 36 IOZ -5 5 µA VOH VOL 2.4 --- --0.4 V V AS4LC4M16 Rev. 1.1 6/05 Austin Semiconductor, Inc. reserves the right to change products or specifications without notice. 7 DRAM D RAM Austin Semiconductor, Inc. AS4LC4M16 ICC OPERATING CONDITIONS AND MAXIMUM LIMITS1,2,3,5,6 (VCC = +3.3V ±0.3V) PARAMETERS STANDBY CURRENT: TTL RAS\ = CAS\ = VIH STANDBY CURRENT: CMOS (RAS\ = CAS\ > VCC - 0.2V; DQs may be left open; Other inputs: VIN > VCC - 0.2V or VIN < 0.2V) OPERATING CURRENT: Random READ/WRITE Average power supply current (RAS\, CAS\, address cycling: tRC = tRC [MIN]) OPERATING CURRENT: EDO PAGE MODE Average power supply current (RAS\ = VIL, CAS\, address cycling: tPC = tPC [MIN]) REFRESH CURRENT: RAS\-ONLY Average power supply current (RAS\ cycling, CAS\ = VIH: tRC = tRC [MIN]) REFRESH CURRENT: CBR Average power supply current (RAS\, CAS\, address cycling: tRC = tRC [MIN]) REFRESH CURRENT: Extended ("S" version only) Average power supply current: CAS\ = 0.2V or CBR cycling; RAS\ = tRAS (MIN); WE\ = VCC - 0.2V; A0 - A10, OE\ and DIN = VCC - 0.2V or 0.2V (DIN may be left open); tRC = 125µS REFRESH CURRENT: Self ("S" version only) Average power supply current: CBR with RAS\ > tRASS (MIN) and CAS\ held LOW; WE\ = VCC - 0.2V; A0 - A10, OE\ and DIN = VCC - 0.2V or 0.2V (DIN may be left open) ICC3 165 150 mA 26 SYM ICC1 -5 MAX 1.5 -6 MAX 1.5 UNITS mA NOTES ICC2 1 1 mA ICC4 125 120 mA 26 ICC5 165 150 mA 22 ICC6 165 150 mA 4, 7, 23 ICC7 1 1 mA 4, 7, 23, 37 ICC8 1 1 mA 4, 7, 37 AS4LC4M16 Rev. 1.1 6/05 Austin Semiconductor, Inc. reserves the right to change products or specifications without notice. 8 DRAM D RAM Austin Semiconductor, Inc. CAPACITANCE2 PARAMETER Input Capacitance: Address Pins Input Capacitance: RAS\, CAS\, WE\, OE\ Input/Output Capacitance: DQ SYM CI1 CI2 CI0 MAX 5 7 7 UNIT pF pF pF AS4LC4M16 AC ELECTRICAL CHARACTERISTICS5,6,7,8,9,10,11,12 (VCC = +3.3V ±0.3V) DESCRIPTION Access time from column address Column-address setup to CAS\ precharge Column-address hold time (referenced to RAS\) Column-address setup time Row-address setup time Column address to WE\ delay time Access time from CAS\ Column-address hold time CAS\ pulse width CAS\ LOW to "Don't Care" during Self Refresh CAS\ hold time (CBR Refresh) Last CAS\ going LOW to first CAS\ to return HIGH CAS\ to output in Low-Z Data output hold after CAS\ LOW CAS\ precharge time Access time from CAS\ precharge CAS\ to RAS\ precharge time CAS\ hold time CAS\ setup time (CBR Refresh) CAS\ to WE\ delay time WRITE command to CAS\ lead time Data-in hold time Data-in setup time Output disable Output enable time OE\ hold time from WE\ during READ-MODIFY-WRITE cycle OE\ HIGH hold time from CAS\ HIGH OE\ HIGH pulse width OE\ LOW to CAS\ HIGH setup time. Output buffer turn-off delay OE\ setup prior to RAS\ during HIDDEN REFRESH cycle AS4LC4M16 Rev. 1.1 6/05 -5 SYMBOL tAA tACH tAR tASC tASR tAWD tCAC tCAH tCAS tCHD tCHR tCLCH tCLZ tCOH tCP tCPA tCRP tCSH tCSR tCWD tCWL tDH tDS tOD tOE tOEH tOEHC tOEP tOES tOFF tORD 8 5 5 4 0 0 12 5 38 5 28 8 8 0 0 12 12 10 10 5 5 0 0 8 8 15 8 5 0 3 8 28 5 45 5 35 10 10 0 0 10,000 12 38 0 0 42 13 10 10 15 10 5 0 3 10 MIN MAX 25 MIN 15 45 0 0 49 -6 MAX 30 UNITS ns ns ns ns ns ns NOTES 28 28 18 29 28 30, 32 15 ns ns 10,000 ns ns ns ns ns ns ns 4, 31 31 29 13, 33 29 31 31 4, 28 18, 28 31 19, 29 19, 29 24, 25 20 25 35 ns ns ns ns ns ns ns ns 15 15 ns ns ns ns ns ns 15 ns ns 17, 24, 29 Austin Semiconductor, Inc. reserves the right to change products or specifications without notice. 9 DRAM D RAM Austin Semiconductor, Inc. AS4LC4M16 AC ELECTRICAL CHARACTERISTICS (Continued)5,6,7,8,9,10,11,12 (VCC = +3.3V ±0.3V) DESCRIPTION EDO-PAGE-MODE READ or WRITE cycle time EDO-PAGE-MODE READ-WRITE cycle time Access time from RAS\ RAS\ to column-address delay time Row address hold time RAS\ pulse width RAS\ pulse width (EDO PAGE MODE) RAS\ pulse width during Self Refresh Random READ or WRITE cycle time RAS\ to CAS\ delay time READ command hold time (referenced to CAS\) READ command setup time Refresh period Refresh period ("S" version) RAS\ precharge time RAS\ to CAS\ precharge time RAS\ precharge time exiting Self Refresh READ command hold time (referenced to RAS\) RAS\ hold time READ-WRITE cycle time RAS\ to WE\ delay time WRITE command to RAS\ lead time Transitioin time (rise or fall) WRITE command hold time WRITE command hold time (referenced to RAS\) WE\ command setup time WE\ to outputs in High-Z WRITE command pulse width WE\ pulse widths to disable outputs WE\ hold time (CBR Refresh) WE\ setup time (CBR Refresh) -5 SYMBOL tPC tPRWC tRAC tRAD tRAH tRAS tRASP tRASS tRC tRCD tRCH tRCS tREF tREF tRP tRPC tRPS tRRH tRSH tRWC tRWD tRWL tT tWCH tWCR tWCS tWHZ tWP tWPZ tWRH tWRP 5 10 8 8 30 5 90 0 13 116 67 13 2 8 38 0 12 5 10 10 10 25 9 7 50 50 80 84 11 0 0 64/24** 100 40 5 105 0 15 140 79 15 2 10 45 0 10,000 125,000* MIN 20 47 MAX MIN 25 56 -6 MAX UNITS NOTES ns ns 34 34 50 12 10 60 60 80 104 14 0 0 60 ns ns ns 15 10,000 125,000* ns ns µs ns ns ns ns 14, 28 16, 30 28 22, 23 23, 38 64/24** 100 ms ms ns ns ns ns ns ns ns ns 16 35 18 25 ns ns ns ns 18, 28 35 15 ns ns ns ns ns NOTES: *For XT Temp (-55°C to +125°C) tRASP (MAX) = 80,000ns for -5 and -6 speed. **64ms Refresh for IT Temp, 24ms Refresh for XT Temp. AS4LC4M16 Rev. 1.1 6/05 Austin Semiconductor, Inc. reserves the right to change products or specifications without notice. 10 DRAM D RAM Austin Semiconductor, Inc. NOTES: 1. All voltages referenced to VSS. 2. This parameter is sampled. VCC = +3.3V; f = 1 MHz; TA = 25°C. 3. I CC i s dependent on output loading and cycle rates. Specified values are obtained with minimum cycle time and the outputs open. 4. Enables on-chip refresh and address counters. 5. The minimum specifications are used only to indicate cycle time at which proper operation over the full temperature range is ensured. 6. An initial pause of 100µs is required after power-up, followed by eight RAS\ refresh cycles (RAS\-ONLY or CBR with WE\ HIGH), before proper device operation is ensured. The eight RAS\ cycle wake-ups should be repeated any time the tREF refresh requirements is exceeded. 7. AC characteristics assume tT = 2.5ns. 8. VIH (MIN) and VIL (MAX) are reference levels for measuring timing of input signals. Transition times are measured between VIH and VIL (or between VIL and VIH). 9. In addition to meeting the transition rate specification, all input signals must transit between VIH and VIL (or between VIL and VIH) in a monotonic manner. 10. If CAS\ and RAS\ = VIH, data output is High-Z. 11. If CAS\ = VIL, data output may contain data from the last valid READ cycle. 12. Measured with a load equivalent to two TTL gates and 100pF; and VOL = 0.8V and VOH = 2V. 13. If CAS\ is LOW at the falling edge of RAS\, output data will be maintained from the previous cycle. To initiate a new cycle and clear the data-out buffer, CAS\ must be pulsed HIGH for tCP. 14. The tRCD (MAX) limit is no longer specified. tRCD (MAX) was specified as a reference point only. If tRCD was greater than the specified tRCD (MAX) limit, then access time was controlled exclusively by tCAC (tRAC [MIN] no longer applied). With our without the tRCD limit, tAA and tCAC must always be met. 15. The tRAD (MAX) limit is no longer specified. tRAD (MAX) was specified as a reference point only. If tRAD was greater than the specified tRAD (MAX) limit, then access time was controlled exclusively by tAA (tRAC and tCAC no longer applied). With or without the tRAD (MAX) limit, tAA, tRAC, and tCAC must always be met. 16. Either tRCH or tRRH must be satisfied for a READ cycle. AS4LC4M16 17. tOFF (MAX) defines the time at which the output achieves the open circuit condition and is not referenced to VOH or VOL. 18. tWCS, tRWD, tAWD, and tCWD are not restrictive operating parameters. tWCS applies to EARLY WRITE cycles. If tWCS > tWCS (MIN), the cycle is an EARLY WRITE cycle and the data output will remain an open circuit throughout the entire cycle. tRWD, tAWD, and tCWD define READ-MODIFY-WRITE cycles. Meeting these limits allows for reading and disabling output data and then applying input data. OE\ held HIGH and WE\ taken LOW after CAS\ goes LOW results in a LATE WRITE (OE\-controlled) cycle. tWCS, tRWD, tCWD, and tAWD are not applicable in a LATE WRITE cycle. 19. These parameters are referenced to CAS\ leading edge in EARLY WRITE cycles and WE\ leading edge in LATE WRITE or READ-MODIFY-WRITE operations are not possible. 20. If OE\ is tied permanently LOW, LATE WRITE, or READMODIFY-WRITE operations are not possible. 21. A HIDDEN REFRESH may also be performed after a WRITE cycle. In this case, WE\ is LOW and OE\ is HIGH. 22. RAS\-ONLY REFRESH that all 4,096 rows of the device be refreshed at least once every 64ms. 23. CBR REFRESH for the device requires that at least 4,096 cycles be completed every 64ms. 24. The DQs go High-Z during READ cycles once tOD or tOFF occur. If CAS\ stays LOW while OE\ is brought HIGH, the DQs will go High-Z. If OE\ is brought back LOW (CAS\ still LOW), the DQs will provide the previous read data. 25. LATE WRITE and READ-MODIFY-WRITE cycles must have both tOD and tOEH met (OE\ HIGH during write cycle) in order to ensure that the output buffers will be open during the WRITE cycle. If OE\ is taken back LOW while CAS\ remains LOW, the DQs will remain open. 26. Column address changed once each cycle. 27. The first CAS\ edge to transition LOW. 28. Output parameter (DQx) is referenced to corresponding CAS\ input; DQ0 - DQ7 by CASL\ and DQ8 - DQ15 by CASH\. 29. Each CASx\ must meet minimum pulse width. 30. The last CASx\ edge to transition HIGH. 31. Last falling CASx\ edge to first rising CASx\ edge. 32. Last rising CASx\ edge to first falling CASx\ edge. 33. Last rising CASx\ edge to next cycles last rising CASx\ edge. 34. Last CASx\ to go LOW. Notes continued on next page. *64ms for IT version, 32ms for XT version. AS4LC4M16 Rev. 1.1 6/05 Austin Semiconductor, Inc. reserves the right to change products or specifications without notice. 11 DRAM D RAM Austin Semiconductor, Inc. NOTES (Continued): 35. VIH overshoot: VIH (MAX) - VCC + 2V for a pulse width £ 3ns, and the pulse width cannot be greater than one third of the cycle rate. VIL undershoot: VIL (MIN) = -2V for a pulse width £ 3ns, and the pulse width cannot be greater then one third of the cycle rate. 36. NC pins are assumed to be left floating and are not tested for leakage. 37. Self refresh and extended refresh for the device requires that at least 4,096 cycles be completed every 128ms. 38. Self refresh version on IT temp parts only. AS4LC4M16 AS4LC4M16 Rev. 1.1 6/05 Austin Semiconductor, Inc. reserves the right to change products or specifications without notice. 12 DRAM D RAM Austin Semiconductor, Inc. READ CYCLE AS4LC4M16 NOTES: 1. tOFF is referenced from rising edge of RAS\ or CAS\, whichever occurs last. AS4LC4M16 Rev. 1.1 6/05 Austin Semiconductor, Inc. reserves the right to change products or specifications without notice. 13 DRAM D RAM Austin Semiconductor, Inc. EARLY WRITE CYCLE AS4LC4M16 AS4LC4M16 Rev. 1.1 6/05 Austin Semiconductor, Inc. reserves the right to change products or specifications without notice. 14 DRAM D RAM Austin Semiconductor, Inc. AS4LC4M16 READ-WRITE CYCLE (LATE WRITE and READ-MODIFY-WRITE cycles) AS4LC4M16 Rev. 1.1 6/05 Austin Semiconductor, Inc. reserves the right to change products or specifications without notice. 15 DRAM D RAM Austin Semiconductor, Inc. EDO-PAGE-MODE READ CYCLE AS4LC4M16 NOTES: * tRASP (MAX) = 80,000ns for XT temperature version. AS4LC4M16 Rev. 1.1 6/05 Austin Semiconductor, Inc. reserves the right to change products or specifications without notice. 16 DRAM D RAM Austin Semiconductor, Inc. AS4LC4M16 EDO-PAGE-MODE EARLY WRITE CYCLE NOTES: * tRASP (MAX) = 80,000ns for XT temperature version. AS4LC4M16 Rev. 1.1 6/05 Austin Semiconductor, Inc. reserves the right to change products or specifications without notice. 17 DRAM D RAM Austin Semiconductor, Inc. AS4LC4M16 EDO-PAGE-MODE READ-WRITE CYCLE (LATE WRITE and READ-MODIFY-WRITE cycles) NOTES: * tRASP (MAX) = 80,000ns for XT temperature version. AS4LC4M16 Rev. 1.1 6/05 Austin Semiconductor, Inc. reserves the right to change products or specifications without notice. 18 DRAM D RAM Austin Semiconductor, Inc. AS4LC4M16 EDO-PAGE-MODE READ EARLY WRITE CYCLE (Pseudo READ-MODIFY-WRITE) NOTES: * tRASP (MAX) = 80,000ns for XT temperature version. AS4LC4M16 Rev. 1.1 6/05 Austin Semiconductor, Inc. reserves the right to change products or specifications without notice. 19 DRAM D RAM Austin Semiconductor, Inc. READ CYCLE (with WE\-controlled disable) AS4LC4M16 AS4LC4M16 Rev. 1.1 6/05 Austin Semiconductor, Inc. reserves the right to change products or specifications without notice. 20 DRAM D RAM Austin Semiconductor, Inc. RAS\-ONLY REFRESH CYCLE (OE\ and WE\ = DON’T CARE) AS4LC4M16 CBR REFRESH CYCLE (Addresses and OE\ = DON’T CARE) NOTES: 1. End of first CBR REFRESH cycle. AS4LC4M16 Rev. 1.1 6/05 Austin Semiconductor, Inc. reserves the right to change products or specifications without notice. 21 DRAM D RAM Austin Semiconductor, Inc. HIDDEN REFRESH CYCLE1 (WE\ = HIGH; OE\ = LOW) AS4LC4M16 NOTES: 1. A HIDDEN REFRESH may also be performed after a WRITE cycle. In this case, WE\ is LOW and OE\ is HIGH. AS4LC4M16 Rev. 1.1 6/05 Austin Semiconductor, Inc. reserves the right to change products or specifications without notice. 22 DRAM D RAM Austin Semiconductor, Inc. SELF REFRESH CYCLE (Addresses and OE\ = DON’T CARE) AS4LC4M16 NOTES: 1. Once tRASS (MIN) is met and RAS\ remains LOW, the DRAM will enter self refresh mode. 2. Once tRPS is satisfied, a complete burst of all rows should be executed if RAS\-only or burst CBR refresh is used. AS4LC4M16 Rev. 1.1 6/05 Austin Semiconductor, Inc. reserves the right to change products or specifications without notice. 23 DRAM D RAM Austin Semiconductor, Inc. AS4LC4M16 MECHANICAL DEFINITIONS (Package Designator DG) AS4LC4M16 Rev. 1.1 6/05 Austin Semiconductor, Inc. reserves the right to change products or specifications without notice. 24 DRAM D RAM Austin Semiconductor, Inc. AS4LC4M16 ORDERING INFORMATION EXAMPLE: AS4LC4M16DG-6S/XT Device Number AS4LC4M16 AS4LC4M16 Package Type DG DG Speed ns -5 -6 Options S S Process /* /* *AVAILABLE PROCESSES XT = Industrial Temperature Range IT = Industrial Temperature Range -55oC to +125oC -40oC to +85oC OPTION DEFINITIONS S = Self Refresh AS4LC4M16 Rev. 1.1 6/05 Austin Semiconductor, Inc. reserves the right to change products or specifications without notice. 25