is42s16400

Integrated Silicon Solution, Inc. — www.issi.com 1Rev. D01/3008

Copyright © 2006 Integrated Silicon Solution, Inc. All rights reserved. ISSI reserves the right to make changes to this specification and its products at any time without notice. ISSI assumes no liability arising out of the application or use of any information, products or services described herein. Customers are advised to obtain the latest version of this device specification before relying on any published information and before placing orders for products.

IS42S16400

FEATURES• Clock frequency: 166, 143 MHz

• Fullysynchronous;allsignalsreferencedtoapositive clock edge

• Internalbankforhidingrowaccess/precharge

• Single3.3Vpowersupply

• LVTTLinterface

• Programmableburstlength – (1, 2, 4, 8, full page)

• Programmableburstsequence: Sequential/Interleave

• Selfrefreshmodes

• 4096refreshcyclesevery64ms

• Randomcolumnaddresseveryclockcycle

• ProgrammableCAS latency (2, 3 clocks)

• Burstread/writeandburstread/singlewrite operations capability

• Burstterminationbyburststopandprechargecommand

• BytecontrolledbyLDQMandUDQM

• Package:400-mil54-pinTSOPII

• Lead-freepackageisavailable

• AvailableinIndustrialTemperature

• PowerDownandDeepPowerDownMode

• PartialArraySelfRefresh

• TemperatureCompensatedSelfRefresh

• OutputDriverStrengthSelection(Pleasecon-tactProductManagerformobilefunctiondetail)

OVERVIEWISSI's64MbSynchronousDRAMIS42S16400isorganizedas 1,048,576 bits x 16-bit x 4-bank for improved performance. ThesynchronousDRAMsachievehigh-speeddatatransferusing pipeline architecture. All inputs and outputs signals refer to the rising edge of the clock input.

1 Meg Bits x 16 Bits x 4 Banks (64-MBIT) SYNCHRONOUS DYNAMIC RAM JANUARY 2008

PIN CONFIGURATIONS54-Pin TSOP (Type II)

VDD

DQ0

VDDQ

DQ1

DQ2

GNDQ

DQ3

DQ4

VDDQ

DQ5

DQ6

GNDQ

DQ7

VDD

LDQM

WE

CAS

RAS

CS

BA0

BA1

A10

A0

A1

A2

A3

VDD

1

2

3

4

5

6

7

8

9

10

11

12

13

14

15

16

17

18

19

20

21

22

23

24

25

26

27

54

53

52

51

50

49

48

47

46

45

44

43

42

41

40

39

38

37

36

35

34

33

32

31

30

29

28

GND

DQ15

GNDQ

DQ14

DQ13

VDDQ

DQ12

DQ11

GNDQ

DQ10

DQ9

VDDQ

DQ8

GND

NC

UDQM

CLK

CKE

NC

A11

A9

A8

A7

A6

A5

A4

GND

PIN DESCRIPTIONSA0-A11 Address Input

BA0,BA1 BankSelectAddress

DQ0toDQ15 DataI/O

CLK SystemClockInput

CKE ClockEnable

CS Chip Select

RAS RowAddressStrobeCommand

CAS Column Address Strobe Command

WE WriteEnable

LDQM LowerBye,Input/OutputMask

UDQM UpperBye,Input/OutputMask

VDD Power

GND Ground

VDDq PowerSupplyforDQPin

GNDq GroundforDQPin

NC No Connection

2 Integrated Silicon Solution, Inc. — www.issi.com Rev. D

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IS42S16400

GENERAL DESCRIPTIONThe 64Mb SDRAM is a high speed CMOS, dynamicrandom-access memory designed to operate in 3.3Vmemory systems containing 67,108,864 bits. Internally configured as a quad-bank DRAM with a synchronousinterface.Each16,777,216-bitbankisorganizedas4,096rows by 256 columns by 16 bits.

The64MbSDRAMincludesanAUTOREFRESHMODE,and a power-saving, power-down mode. All signals are registeredonthepositiveedgeoftheclocksignal,CLK.AllinputsandoutputsareLVTTLcompatible.

The64MbSDRAMhastheabilitytosynchronouslyburstdata at a high data rate with automatic column-address generation, the ability to interleave between internal banks to hide precharge time and the capability to randomly change column addresses on each clock cycle during burst access.

A self-timed row precharge initiated at the end of the burst sequenceisavailablewiththeAUTOPRECHARGEfunctionenabled. Precharge one bank while accessing one of the

other three banks will hide the precharge cycles and provide seamless, high-speed, random-access operation.

SDRAM read and write accesses are burst oriented starting at a selected location and continuing for a programmed number of locations in a programmed sequence. Theregistration of an ACTIVE command begins accesses,followedbyaREADorWRITEcommand.TheACTIVEcommand in conjunction with address bits registered are usedtoselect thebankandrowtobeaccessed(BA0,BA1selectthebank;A0-A11selecttherow).TheREADor WRITE commands in conjunction with address bitsregistered are used to select the starting column location for the burst access.

ProgrammableREADorWRITEburstlengthsconsistof1, 2, 4 and 8 locations, or full page, with a burst terminate option.

CLKCKECSRASCASWEA10

A9A8A7A6A5A4A3A2A1A0

BA0BA1

A11

COMMANDDECODER

&CLOCK

GENERATOR MODEREGISTER

REFRESHCONTROLLER

REFRESHCOUNTER

SELF

REFRESH

CONTROLLER

ROWADDRESS

LATCH MU

LTIP

LEX

ER

COLUMNADDRESS LATCH

BURST COUNTER

COLUMNADDRESS BUFFER

COLUMN DECODER

DATA INBUFFER

DATA OUTBUFFER

DQM

DQ 0-15

VDD/VDDQ

GND/GNDQ

12

12

8

12

12

8

16

16 16

16

256K(x 16)

4096

4096

4096

RO

W D

EC

OD

ER 4096

MEMORY CELLARRAY

BANK 0

SENSE AMP I/O GATE

BANK CONTROL LOGIC

ROWADDRESSBUFFER

FUNCTIONAL BLOCK DIAGRAM

Integrated Silicon Solution, Inc. — www.issi.com 3Rev. D01/30/08

IS42S16400

PIN FUNCTIONS Symbol TSOP Pin No. Type Function (In Detail)

A0-A11 23to26 InputPin AddressInputs:A0-A11aresampledduringtheACTIVE

29to34 command(row-addressA0-A11)andREAD/WRITEcommand(A0-A7

22, 35 with A10 defining auto precharge) to select one location out of the memory array intherespectivebank.A10issampledduringaPRECHARGEcommandtodeter-mine if all banks are to be precharged (A10 HIGH) or bank selected by BA0,BA1(LOW).Theaddressinputsalsoprovidetheop-codeduringaLOADMODEREGISTERcommand.

BA0,BA1 20,21 InputPin BankSelectAddress:BA0andBA1defineswhichbanktheACTIVE,READ,WRITEorPRECHARGEcommandisbeingapplied.

CAS 17 InputPin CAS, in conjunction with the RAS and WE, forms the device command. See the "CommandTruthTable"fordetailsondevicecommands.

CKE 37 InputPin TheCKEinputdetermineswhethertheCLKinputisenabled.ThenextrisingedgeoftheCLKsignalwillbevalidwhenisCKEHIGHandinvalidwhenLOW.WhenCKEisLOW,thedevicewillbeineitherpower-downmode,clocksuspendmode,orselfrefresh mode. CKEisan asynchronous input.

CLK 38 InputPin CLKisthemasterclockinputforthisdevice.ExceptforCKE,allinputstothisdeviceare acquired in synchronization with the rising edge of this pin.

CS 19 InputPin TheCS input determines whether command input is enabled within the device. Command input is enabled when CSisLOW,anddisabledwithCSisHIGH.Thedevice remains in the previous state when CS is HIGH.

DQ0to 2,4,5,7,8,10, DQPin DQ0toDQ15areI/Opins.I/Othroughthesepinscanbecontrolledinbyteunits

DQ15 11,13, 42, 44, 45, usingtheLDQMandUDQMpins.

47, 48, 50, 51, 53

LDQM, 15,39 InputPin LDQMandUDQMcontrolthelowerandupperbytesoftheI/Obuffers.Inread

UDQM mode,LDQMandUDQMcontroltheoutputbuffer.WhenLDQMorUDQMisLOW,thecorrespondingbufferbyteisenabled,andwhenHIGH,disabled.TheoutputsgototheHIGHimpedancestatewhenLDQM/UDQMisHIGH.Thisfunctioncor-responds to OEinconventionalDRAMs.Inwritemode,LDQMandUDQMcontroltheinputbuffer.WhenLDQMorUDQMisLOW,thecorrespondingbufferbyteisen-abled,anddatacanbewrittentothedevice.WhenLDQMorUDQMisHIGH,inputdata is masked and cannot be written to the device.

RAS 18 InputPin RAS, in conjunction with CAS and WE, forms the device command. See the "Com-mandTruthTable"itemfordetailsondevicecommands.

WE 16 InputPin WE, in conjunction with RAS and CAS, forms the device command. See the "Com-mandTruthTable"itemfordetailsondevicecommands.

VDDq 3,9,43,49 PowerSupplyPin VDDq is the output buffer power supply.

VDD 1,14,27 PowerSupplyPin VDD is the device internal power supply.

GNDq 6,12,46,52 PowerSupplyPin GNDq is the output buffer ground.

GND 28,41,54 PowerSupplyPin GND is the device internal ground.


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FUNCTION (InDetail)A0-A11areaddressinputssampledduringtheACTIVE(row-address A0-A11)andREAD/WRITEcommand(A0-A7 withA10definingautoPRECHARGE). A10 is sampled during aPRECHARGEcommandtodetermineifallbanksaretobePRECHARGED(A10 HIGH)orbankselectedbyBA0,BA1(LOW).Theaddressinputsalsoprovidetheop-codeduringaLOADMODEREGISTERcommand.

BankSelectAddress(BA0andBA1) defines which bank theACTIVE,READ,WRITEorPRECHARGEcommandis being applied.

CAS, in conjunction with the RAS and WE, forms the device command.Seethe“CommandTruthTable”fordetailsondevice commands.

TheCKEinputdetermineswhethertheCLKinputisen-abled.ThenextrisingedgeoftheCLKsignalwillbevalidwhenisCKEHIGHandinvalidwhenLOW.WhenCKEisLOW,thedevicewillbeineitherpower-downmode,CLOCKSUSPENDmode,orSELF-REFRESHmode.CKEisanasynchronous input.

CLKisthemasterclockinputforthisdevice.ExceptforCKE,allinputstothisdeviceareacquiredinsynchroniza-tion with the rising edge of this pin.

TheCS input determines whether command input is en-abled within the device. Command input is enabled when CS isLOW,anddisabledwithCS isHIGH.Thedeviceremains in the previous state when CS isHIGH.DQ0toDQ15areDQpins.DQthroughthesepinscanbecontrolledinbyteunitsusingtheLDQMandUDQMpins.

LDQMandUDQMcontrolthelowerandupperbytesoftheDQbuffers.Inreadmode,LDQMandUDQMcontrolthe output buffer.When LDQM or UDQM is LOW, thecorresponding buffer byte is enabled, and when HIGH, disabled.TheoutputsgototheHIGHImpedanceStatewhenLDQM/UDQMisHIGH.Thisfunctioncorrespondsto OE inconventionalDRAMs.Inwritemode,LDQMandUDQMcontroltheinputbuffer.WhenLDQMorUDQMisLOW,thecorrespondingbufferbyteisenabled,anddatacanbewritten to thedevice.WhenLDQMorUDQMisHIGH, input data is masked and cannot be written to the device.

RAS, in conjunction with CAS and WE , forms the device command.Seethe“CommandTruthTable”itemfordetailson device commands.

WE , in conjunction with RAS and CAS , forms the device command.Seethe“CommandTruthTable”itemfordetailson device commands.

VDDq is the output buffer power supply.

VDD is the device internal power supply.

GNDq is the output buffer ground.

GNDisthedeviceinternalground.

READTheREADcommandselectsthebankfromBA0,BA1inputsand starts a burst read access to an active row. Inputs A0-A7 provides the starting column location. When A10 is HIGH,thiscommandfunctionsasanAUTOPRECHARGEcommand. When the auto precharge is selected, the row beingaccessedwillbeprechargedattheendoftheREADburst.TherowwillremainopenforsubsequentaccesseswhenAUTOPRECHARGE isnot selected. DQ’s readdataissubjecttothelogiclevelontheDQMinputstwoclocksearlier.WhenagivenDQMsignalwasregisteredHIGH,thecorrespondingDQ’swillbeHigh-Ztwoclockslater.DQ’swillprovidevaliddatawhentheDQMsignalwasregisteredLOW.

WRITEA burst write access to an active row is initiated with the WRITE command. BA0, BA1 inputs selects the bank,and the starting column location is provided by inputs A0-A7.Whether or notAUTO-PRECHARGE is used isdetermined by A10.

TherowbeingaccessedwillbeprechargedattheendoftheWRITEburst, ifAUTOPRECHARGE isselected. IfAUTOPRECHARGEisnotselected,therowwillremainopen for subsequent accesses.

A memory array is written with corresponding input data onDQ’sandDQMinputlogiclevelappearingatthesametime.DatawillbewrittentomemorywhenDQMsignalisLOW.WhenDQMisHIGH,thecorrespondingdatainputswillbeignored,andaWRITEwillnotbeexecutedtothatbyte/column location.

PRECHARGEThePRECHARGEcommand isused todeactivate theopen row in a particular bank or the open row in all banks. BA0,BA1canbeusedtoselectwhichbankisprechargedor they are treated as “Don’t Care”. A10 determinedwhether one or all banks are precharged. After execut-ing this command, the next command for the selected banks(s) is executed after passage of the period tRP, which istheperiodrequiredforbankprecharging.Onceabankhas been precharged, it is in the idle state and must be activatedpriortoanyREADorWRITEcommandsbeingissued to that bank.

AUTO PRECHARGETheAUTOPRECHARGEfunctionensuresthatthepre-charge is initiated at the earliest valid stage within a burst. Thisfunctionallowsforindividual-bankprechargewithoutrequiringanexplicitcommand.A10toenablestheAUTOPRECHARGEfunctioninconjunctionwithaspecificREADorWRITEcommand.ForeachindividualREADorWRITEcommand, auto precharge is either enabled or disabled.


IS42S16400

AUTOPRECHARGEdoesnotapplyexceptinfull-pageburst mode. Upon completion of the READ or WRITEburst, a precharge of the bank/row that is addressed is automatically performed.

AUTO REFRESH COMMANDThiscommandexecutestheAUTOREFRESHoperation.Therowaddressandbanktoberefreshedareautomaticallygeneratedduringthisoperation. Thestipulatedperiod(trc) is required for a single refresh operation, and no other com-mandscanbeexecutedduringthisperiod. Thiscommandisexecutedatleast4096timesevery64ms.DuringanAUTOREFRESHcommand,addressbitsare“Don’tCare”.ThiscommandcorrespondstoCBRAuto-refresh.

SELF REFRESHDuringtheSELFREFRESHoperation,therowaddresstobe refreshed, the bank, and the refresh interval are gen-eratedautomaticallyinternally.SELFREFRESHcanbeusedtoretaindataintheSDRAMwithoutexternalclocking,eveniftherestofthesystemispowereddown.TheSELFREFRESHoperationisstartedbydroppingtheCKEpinfromHIGHtoLOW.DuringtheSELFREFRESHoperationallotherinputstotheSDRAMbecome“Don’tCare”.Thedevice must remain in self refresh mode for a minimum period equal to tras or may remain in self refresh mode foranindefiniteperiodbeyondthat.TheSELF-REFRESHoperationcontinuesaslongastheCKEpinremainsLOWand there is no need for external control of any other pins. Thenextcommandcannotbeexecuteduntilthedeviceinternal recovery period (trc) has elapsed. Once CKEgoesHIGH,theNOPcommandmustbeissued(minimum of two clocks) to provide time for the completion of any internal refresh in progress. After the self-refresh, since it is impossible to determine the address of the last row to berefreshed,anAUTO-REFRESHshouldimmediatelybeperformed for all addresses.

BURST TERMINATETheBURSTTERMINATEcommand forcibly terminatesthe burst read and write operations by truncating either fixed-length or full-page bursts and the most recently registeredREADorWRITEcommandpriortotheBURSTTERMINATE.

COMMAND INHIBITCOMMANDINHIBITpreventsnewcommandsfrombeingexecuted.Operationsinprogressarenotaffected,apartfromwhethertheCLKsignalisenabled

NO OPERATION When CSislow,theNOPcommandpreventsunwantedcommands from being registered during idle or wait states.

LOAD MODE REGISTERDuringtheLOADMODEREGISTERcommandthemoderegisterisloadedfromA0-A11.Thiscommandcanonlybe issued when all banks are idle.

ACTIVE COMMANDWhen the ACTIVE COMMAND is activated, BA0, BA1inputs selects a bank to be accessed, and the address inputsonA0-A11selectstherow.UntilaPRECHARGEcommand is issued to the bank, the row remains open for accesses.


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TRUTH TABLE – COMMANDS AND DQM OPERATION(1)

FUNCTION CS RAS CAS WE DQM ADDR DQs

COMMANDINHIBIT(NOP) H X X X X X X

NOOPERATION(NOP) L H H H X X X

ACTIVE(Selectbankandactivaterow)(3) L L H H X Bank/Row X

READ(Selectbank/column,startREADburst)(4) L H L H L/H(8) Bank/Col X

WRITE(Selectbank/column,startWRITEburst)(4) L H L L L/H(8) Bank/Col Valid

BURSTTERMINATE L H H L X X Active

PRECHARGE(Deactivaterowinbankorbanks)(5) L L H L X Code X

AUTOREFRESHorSELFREFRESH(6,7) L L L H X X X (Enterselfrefreshmode)

LOADMODEREGISTER(2) L L L L X Op-Code X

WriteEnable/OutputEnable(8) — — — — L — Active

WriteInhibit/OutputHigh-Z(8) — — — — H — High-ZNOTES:1. CKEisHIGHforallcommandsexceptSELFREFRESH.2. A0-A11 define the op-code written to the mode register.3. A0-A11providerowaddress,andBA0,BA1determinewhichbankismadeactive.4. A0-A7(x16)providecolumnaddress;A10HIGHenablestheautoprechargefeature(nonpersistent),whileA10LOWdisables

autoprecharge;BA0,BA1determinewhichbankisbeingreadfromorwrittento.5. A10LOW:BA0,BA1determinethebankbeingprecharged.A10HIGH:AllbanksprechargedandBA0,BA1are“Don’tCare.”6. AUTOREFRESHifCKEisHIGH,SELFREFRESHifCKEisLOW.7. Internalrefreshcountercontrolsrowaddressing;allinputsandI/Osare“Don’tCare”exceptforCKE.8. ActivatesordeactivatestheDQsduringWRITEs(zero-clockdelay)andREADs(two-clockdelay).


IS42S16400

TRUTH TABLE – CURRENT STATE BANK n, COMMAND TO BANK n (1-6)

CURRENTSTATE COMMAND(ACTION) CS RAS CAS WE

Any COMMANDINHIBIT(NOP/Continuepreviousoperation) H X X X

NOOPERATION(NOP/Continuepreviousoperation) L H H H

Idle ACTIVE(Selectandactivaterow) L L H H

AUTOREFRESH(7) L L L H

LOADMODEREGISTER(7) L L L L

PRECHARGE(11) L L H L

RowActive READ(SelectcolumnandstartREADburst)(10) L H L H

WRITE(SelectcolumnandstartWRITEburst)(10) L H L L

PRECHARGE(Deactivaterowinbankorbanks)(8) L L H L

Read READ(SelectcolumnandstartnewREADburst)(10) L H L H

(Auto WRITE(SelectcolumnandstartWRITEburst)(10) L H L L

Precharge PRECHARGE(TruncateREADburst,startPRECHARGE)(8) L L H L

Disabled) BURSTTERMINATE(9) L H H L

Write READ(SelectcolumnandstartREADburst)(10) L H L H

(Auto WRITE(SelectcolumnandstartnewWRITEburst)(10) L H L L

Precharge PRECHARGE(TruncateWRITEburst,startPRECHARGE)(8) L L H L

Disabled) BURSTTERMINATE(9) L H H LNOTE: 1.ThistableapplieswhenCKEn-1wasHIGHandCKEnisHIGH(seeTruthTable-CKE)andaftertxsr has been met (if the

previous state was SELFREFRESH). 2.Thistableisbank-specific,exceptwherenoted;i.e.,thecurrentstateisforaspecificbankandthecommandsshownarethose

allowedtobeissuedtothatbankwheninthatstate.Exceptionsarecoveredinthenotesbelow.

TRUTH TABLE – CKE (1-4)

CURRENT STATE COMMANDn ACTIONn CKEn-1 CKEn

Power-Down X MaintainPower-Down L L

SelfRefresh X MaintainSelfRefresh L L

ClockSuspend X MaintainClockSuspend L L

Power-Down(5) COMMANDINHIBITorNOP ExitPower-Down L H

SelfRefresh(6) COMMANDINHIBITorNOP ExitSelfRefresh L H

Clock Suspend(7) X ExitClockSuspend L H

AllBanksIdle COMMANDINHIBITorNOP Power-DownEntry H L

AllBanksIdle AUTOREFRESH SelfRefreshEntry H L

ReadingorWriting VALID ClockSuspendEntry H L

See TRUTH TABLE – CURRENT STATE BANK n, COMMAND TO BANK n H HNOTES: 1. CKEnisthelogicstateofCKEatclockedgen;CKEn-1 wasthestateofCKEatthepreviousclockedge.2. CurrentstateisthestateoftheSDRAMimmediatelypriortoclockedgen.3. COMMANDnisthecommandregisteredatclockedgen,andACTONnisaresultofCOMMANDn.4. All states and sequences not shown are illegal or reserved.5. Exitingpower-downatclockedgen will put the device in the all banks idle state in time for clock edge n+1 (provided that tcks is

met).6. Exitingselfrefreshatclockedgen will put the device in all banks idle state once txsrismet.COMMANDINHIBITorNOP

commands should be issued on clock edges occurring during the txsrperiod.AminimumoftwoNOPcommandsmustbesentduring txsr period.

7. After exiting clock suspend at clock edge n, the device will resume operation and recognize the next command at clock edge n+1.


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3. Current state definitions: Idle:Thebankhasbeenprecharged,andtrp has been met. RowActive:Arowinthebankhasbeenactivated,andtrcD has been met. No data bursts/accesses and no register

accesses are in progress. Read:AREADbursthasbeeninitiated,withautoprechargedisabled,andhasnotyetterminatedorbeentermi-

nated. Write:AWRITEbursthasbeeninitiated,withautoprechargedisabled,andhasnotyetterminatedorbeentermi-

nated. 4.Thefollowingstatesmustnotbeinterruptedbyacommandissuedtothesamebank.COMMANDINHIBITorNOPcommands,

or allowable commands to the other bank should be issued on any clock edge occurring during these states. Allowable com-mandstotheotherbankaredeterminedbyitscurrentstateandCURRENTSTATEBANKntruthtables.

Precharging:StartswithregistrationofaPRECHARGEcommandandendswhentrpismet.Oncetrp is met, the bank will be in the idle state.

RowActivating:StartswithregistrationofanACTIVEcommandandendswhentrcDismet.OncetrcD is met, the bank will be in the row active state.

Readw/Auto PrechargeEnabled:StartswithregistrationofaREADcommandwithautoprechargeenabledandendswhentrp has been

met.Oncetrp is met, the bank will be in the idle state. Write w/Auto PrechargeEnabled:StartswithregistrationofaWRITEcommandwithautoprechargeenabledandendswhentrp has been

met.Oncetrp is met, the bank will be in the idle state. 5.Thefollowingstatesmustnotbeinterruptedbyanyexecutablecommand;COMMANDINHIBITorNOPcommandsmustbe

applied on each positive clock edge during these states. Refreshing:StartswithregistrationofanAUTOREFRESHcommandandendswhentrcismet.Oncetrc is met, the

SDRAMwillbeintheallbanksidlestate. Accessing Mode Register:StartswithregistrationofaLOADMODEREGISTERcommandandendswhentmrDhasbeenmet.Once

tmrDismet,theSDRAMwillbeintheallbanksidlestate. PrechargingAll:StartswithregistrationofaPRECHARGEALLcommandandendswhentrpismet.Oncetrp is met, all

banks will be in the idle state. 6. All states and sequences not shown are illegal or reserved. 7.Notbank-specific;requiresthatallbanksareidle. 8.Mayormaynotbebank-specific;ifallbanksaretobeprecharged,allmustbeinavalidstateforprecharging. 9.Notbank-specific;BURSTTERMINATEaffectsthemostrecentREADorWRITEburst,regardlessofbank.10.READsorWRITEslistedintheCommand(Action)columnincludeREADsorWRITEswithautoprechargeenabledand

READsorWRITEswithautoprechargedisabled.11.DoesnotaffectthestateofthebankandactsasaNOPtothatbank.


IS42S16400

TRUTH TABLE – CURRENT STATE BANK n, COMMAND TO BANK m (1-6)

CURRENTSTATE COMMAND(ACTION) CS RAS CAS WE

Any COMMANDINHIBIT(NOP/Continuepreviousoperation) H X X X

NOOPERATION(NOP/Continuepreviousoperation) L H H H

Idle AnyCommandOtherwiseAllowedtoBankm X X X X

Row ACTIVE(Selectandactivaterow) L L H H

Activating, READ(SelectcolumnandstartREADburst)(7) L H L H

Active,or WRITE(SelectcolumnandstartWRITEburst)(7) L H L L

Precharging PRECHARGE L L H L

Read ACTIVE(Selectandactivaterow) L L H H

(Auto READ(SelectcolumnandstartnewREADburst)(7,10) L H L H

Precharge WRITE(SelectcolumnandstartWRITEburst)(7,11) L H L L

Disabled) PRECHARGE(9) L L H L

Write ACTIVE(Selectandactivaterow) L L H H

(Auto READ(SelectcolumnandstartREADburst)(7,12) L H L H

Precharge WRITE(SelectcolumnandstartnewWRITEburst)(7,13) L H L L

Disabled) PRECHARGE(9) L L H L

Read ACTIVE(Selectandactivaterow) L L H H

(WithAuto READ(SelectcolumnandstartnewREADburst)(7,8,14) L H L H

Precharge) WRITE(SelectcolumnandstartWRITEburst)(7,8,15) L H L L

PRECHARGE(9) L L H L

Write ACTIVE(Selectandactivaterow) L L H H

(WithAuto READ(SelectcolumnandstartREADburst)(7,8,16) L H L H

Precharge) WRITE(SelectcolumnandstartnewWRITEburst)(7,8,17) L H L L

PRECHARGE(9) L L H LNOTE: 1.ThistableapplieswhenCKEn-1wasHIGHandCKEnisHIGH(TruthTable-CKE)andaftertxsr has been met (if the previ-

ous state was self refresh). 2.Thistabledescribesalternatebankoperation,exceptwherenoted;i.e.,thecurrentstateisforbankn and the commands

shown are those allowed to be issued to bank m (assuming that bank m is in such a state that the given command is allowable).Excep-tions are covered in the notes below.

3. Current state definitions: Idle:Thebankhasbeenprecharged,andtrp has been met. RowActive:Arowinthebankhasbeenactivated,andtrcD has been met. No data bursts/accesses and no register

accesses are in progress. Read:AREADbursthasbeeninitiated,withautoprechargedisabled,andhasnotyetterminatedorbeentermi-

nated. Write:AWRITEbursthasbeeninitiated,withautoprechargedisabled,andhasnotyetterminatedorbeentermi-

nated. Readw/Auto PrechargeEnabled:StartswithregistrationofaREADcommandwithautoprechargeenabled,andendswhentrp has been

met.Oncetrp is met, the bank will be in the idle state. Write w/Auto PrechargeEnabled:StartswithregistrationofaWRITEcommandwithautoprechargeenabled,andendswhentrp has been

met.Oncetrp is met, the bank will be in the idle state. 4.AUTOREFRESH,SELFREFRESHandLOADMODEREGISTERcommandsmayonlybeissuedwhenallbanksareidle. 5.ABURSTTERMINATEcommandcannotbeissuedtoanotherbank;itappliestothebankrepresentedbythecurrentstate

only. 6. All states and sequences not shown are illegal or reserved. 7.READsorWRITEstobankmlistedintheCommand(Action)columnincludeREADsorWRITEswithautoprechargeenabled

andREADsorWRITEswithautoprechargedisabled.


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IS42S16400

8.CONCURRENTAUTOPRECHARGE:BanknwillinitiatetheAUTOPRECHARGEcommandwhenitsbursthasbeeninter-ruptedbybankm’sburst.

9.Burstinbankncontinuesasinitiated.10.ForaREADwithoutautoprechargeinterruptedbyaREAD(withorwithoutautoprecharge),theREADtobankmwillinterrupt

theREADonbankn,CASlatencylater(ConsecutiveREADBursts).11.ForaREADwithoutautoprechargeinterruptedbyaWRITE(withorwithoutautoprecharge),theWRITEtobankmwillinter-

rupttheREADonbanknwhenregistered(READtoWRITE).DQMshouldbeusedoneclockpriortotheWRITEcommandtoprevent bus contention.

12.ForaWRITEwithoutautoprechargeinterruptedbyaREAD(withorwithoutautoprecharge),theREADtobankmwillinterrupttheWRITEonbanknwhenregistered(WRITEtoREAD),withthedata-outappearingCASlatencylater.ThelastvalidWRITEtobanknwillbedata-inregisteredoneclockpriortotheREADtobankm.

13.ForaWRITEwithoutautoprechargeinterruptedbyaWRITE(withorwithoutautoprecharge),theWRITEtobankmwillinter-rupttheWRITEonbanknwhenregistered(WRITEtoWRITE).ThelastvalidWRITEtobanknwillbedata-inregisteredoneclockpriortotheREADtobankm.

14.ForaREADwithautoprechargeinterruptedbyaREAD(withorwithoutautoprecharge),theREADtobankmwillinterrupttheREADonbankn,CASlatencylater.ThePRECHARGEtobanknwillbeginwhentheREADtobankmisregistered(FigCAP1).

15.ForaREADwithautoprechargeinterruptedbyaWRITE(withorwithoutautoprecharge),theWRITEtobankmwillinterrupttheREADonbanknwhenregistered.DQMshouldbeusedtwoclockspriortotheWRITEcommandtopreventbuscontention.ThePRECHARGEtobanknwillbeginwhentheWRITEtobankmisregistered(FigCAP2).

16.ForaWRITEwithautoprechargeinterruptedbyaREAD(withorwithoutautoprecharge),theREADtobankmwillinterrupttheWRITEonbanknwhenregistered,withthedata-outappearingCASlatencylater.ThePRECHARGEtobanknwillbeginafter tWR is met, where twrbeginswhentheREADtobankmisregistered.ThelastvalidWRITEtobanknwillbedata-inregis-teredoneclockpriortotheREADtobankm(FigCAP3).

17.ForaWRITEwithautoprechargeinterruptedbyaWRITE(withorwithoutautoprecharge),theWRITEtobankmwillinterrupttheWRITEonbanknwhenregistered.ThePRECHARGEtobanknwillbeginaftertwrismet,wheretWRbeginswhentheWRITEtobankmisregistered.ThelastvalidWRITEtobanknwillbedataregisteredoneclockpriortotheWRITEtobankm(FigCAP4).


IS42S16400

ABSOLUTE MAXIMUM RATINGS(1)

Symbol Parameters Rating Unit

VDD max MaximumSupplyVoltage –1.0to+4.6 V VDDq max MaximumSupplyVoltageforOutputBuffer –1.0to+4.6 V ViN InputVoltage –1.0toVDDq +0.5 V Vout OutputVoltage –1.0toVDDq +0.5 V PD max AllowablePowerDissipation 1 W Ics output Shorted Current 50 mA Topr operatingTemperature Com. 0to+70 °C Ind. -40to+85 °C Tstg StorageTemperature –65to+150 °C

DC RECOMMENDED OPERATING CONDITIONS(2) (AtTa=0to+70°C)

Symbol Parameter Min. Typ. Max. Unit

VDD, VDDq SupplyVoltage 3.0 3.3 3.6 V Vih InputHighVoltage(3) 2.0 — VDD +0.3 V Vil InputLowVoltage(4) -0.3 — +0.8 V

CAPACITANCE CHARACTERISTICS(1,2) (AtTa=0to+25°C,VDD=VDDq=3.3±0.3V,f=1MHz)

Symbol Parameter Typ. Max. Unit

CiN InputCapacitance:AddressandControl — 3.8 pF Cclk InputCapacitance:(CLK) — 3.5 pF CI/O DataInput/OutputCapacitance:I/O0-I/O15 — 6.5 pFNotes:1. StressgreaterthanthoselistedunderABSOLUTEMAXIMUMRATINGSmaycausepermanentdamagetothedevice.Thisisa

stress rating only and functional operation of the device at these or any other conditions above those indicated in the operational sectionsofthisspecificationisnotimplied.Exposuretoabsolutemaximumratingconditionsforextendedperiodsmayaffectreliability.

2. AllvoltagesarereferencedtoGND.3.Vih(max)=VDDq+2.0Vwithapulsewidth<3ns.4.Vil(min)=GND-2.0Vwithapulsewidth<3ns.


01/30/08

IS42S16400

DC ELECTRICAL CHARACTERISTICS (RecommendedOperationConditionsunlessotherwisenoted.)

Symbol Parameter Test Condition Speed Min. Max. Unit iil InputLeakageCurrent 0V≤ViN ≤VDD, with pins other than –5 5 µA thetestedpinat0V iol OutputLeakageCurrent Outputisdisabled,0V≤ Vout ≤VDD –5 5 µA Voh OutputHighVoltageLevel iout=–2mA 2.4 — V Vol OutputLowVoltageLevel iout=+2mA — 0.4 V

icc1 OperatingCurrent(1,2) OneBankOperation,CASlatency=3Com. -6 — 95 mA BurstLength=1 Com. -7 — 85 mA trc ≥ trc (min.) Ind. -6 — 155 mA Iout = 0mA Ind. -7 — 145 icc2p PrechargeStandbyCurrent CKE≤ Vil (max) tck = 15ns Com. — — 2 mA Ind. — — 4 mA Icc2ps (InPower-DownMode) tck = ∞ Com. — — 2 mA Ind. — — 3 mA icc2N(3) PrechargeStandbyCurrent CKE≥ Vih (miN) tck = 15ns — — 20 mA Icc2Ns (InNonPower-DownMode) tck = ∞ Com. — — 15 mA Ind. — — 15 mA icc3p ActiveStandbyCurrent CKE≤ Vil (max) tck = 10ns Com. — — 7 mA Ind. — — 7 mA icc3ps (InPower-DownMode) tck = ∞ Com. — — 5 mA Ind. — — 5 mA icc3N(3) ActiveStandbyCurrent CKE≥ Vih (miN) tck = 15ns — — 30 mA Icc3Ns (InNonPower-DownMode) tck = ∞ Com. — — 25 mA Ind. — — 25 mA icc4 OperatingCurrent tck = tck (miN) CAS latency = 3 Com. -6 — 130 mA (InBurstMode)(1) Iout = 0mA Com. -7 — 100 mA BL=4;4banksactivated Ind. -6 — 140 mA Ind. -7 — 110 mA icc5 Auto-RefreshCurrent trc = trc (miN) CAS latency = 3 Com. -6 — 150 mA tclk = tclk (miN) Com. -7 — 130 mA Ind. -6 — 170 mA Ind. -7 — 150 mA icc6 Self-RefreshCurrent CKE≤0.2V — — 2 mANotes:1. Thesearethevaluesattheminimumcycletime.Sincethecurrentsaretransient,thesevaluesdecreaseasthecycletimein-

creases.Alsonotethatabypasscapacitorofatleast0.01µFshouldbeinsertedbetweenVDDandGNDforeachmemorychipto suppress power supply voltage noise (voltage drops) due to these transient currents.

2. Icc1 and Icc4dependontheoutputload.ThemaximumvaluesforIcc1 and Icc4 are obtained with the output open state.3. Input signal chnage once per 30ns.


IS42S16400

AC ELECTRICAL CHARACTERISTICS (1,2,3)

-6 -7 Symbol Parameter Min. Max. Min. Max. Units tck3 ClockCycleTime CASLatency=3 6 — 7 — ns tck2 CASLatency=2 7.5 — 7.5 — ns

tac3 AccessTimeFromCLK(4,6) CASLatency=3 — 5 — 5.4 ns tac2 CASLatency=2 — 6 — 6 ns

tchi CLKHIGHLevelWidth 2 — 2.5 — ns

tcl CLKLOWLevelWidth 2 — 2.5 — ns

toh3 OutputDataHoldTime(6) CASLatency=3 2.5 — 2.7 — ns toh2 CAS Latency=2 2.5 — 3 — ns

tlz OutputLOWImpedanceTime 0 — 0 — ns

thz3 OutputHIGHImpedanceTime(5) CASLatency=3 — 5 — 5.4 ns thz2 CASLatency=2 — 6 — 6 ns

tDs InputDataSetupTime 1.5 — 1.5 — ns

tDh InputDataHoldTime 0.8 — 0.8 — ns

tas AddressSetupTime 1.5 — 1.5 — ns

tah AddressHoldTime 0.8 — 0.8 — ns

tcks CKESetupTime 1.5 — 1.5 — ns

tckh CKEHoldTime 0.8 — 0.8 — ns

tcka CKEtoCLKRecoveryDelayTime 1CLK+3 — 1CLK+3 — ns

tcs CommandSetupTime(CS, RAS, CAS, WE,DQM) 1.5 — 2.0 — ns

tch CommandHoldTime(CS, RAS, CAS, WE,DQM) 0.8 — 1 — ns

trc CommandPeriod(REFtoREF/ACTtoACT) 60 — 63 — ns

tras CommandPeriod(ACTtoPRE) 42 100,000 42 100,000 ns

trp CommandPeriod(PREtoACT) 18 — 20 — ns

trcD ActiveCommandToRead/WriteCommandDelayTime 18 — 20 — ns

trrD CommandPeriod(ACT[0]toACT[1]) 12 — 14 — ns

tDpl or InputDataToPrecharge CASLatency=3 2CLK — 2CLK — ns twr CommandDelaytime CAS Latency=2 2CLK — 2CLK — ns

tDal InputDataToActive/Refresh CASLatency=3 2CLK+trp — 2CLK+trp — ns CommandDelaytime(DuringAuto-Precharge) CAS Latency=2 2CLK+trp — 2CLK+trp — ns

tt TransitionTime 1 10 1 10 ns

tref RefreshCycleTime(4096) — 64 — 64 msNotes:1. Whenpowerisfirstapplied,memoryoperationshouldbestarted200µsafterVDDandVDDq reach their stipulated voltages. Also

note that the power-on sequence must be executed before starting memory operation.2. measured with tt = 1 ns.3. Thereferencelevelis1.4Vwhenmeasuringinputsignaltiming.RiseandfalltimesaremeasuredbetweenVih (min.)andVil

(max.).4. Accesstimeismeasuredat1.4Vwiththeloadshowninthefigurebelow.5. Thetimethz (max.)isdefinedasthetimerequiredfortheoutputvoltagetotransitionby±200mVfromVoh (min.)orVol (max.)

when the output is in the high impedance state.6. If clock rising time is longer than 1ns, tr/2 - 0.5ns should be added to the parameter.


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IS42S16400

AC TEST CONDITIONS (Input/OutputReferenceLevel:1.4V)

I/O

50 Ω+1.5V

50 pF

Input Load Output Load

2.0V

1.4V

0.8V

CLK

INPUT

OUTPUT

tCHI

tCH

tACtOH

tCS

tCK

tCL

2.0V

1.4V

1.4V 1.4V

0.8V

OPERATING FREQUENCY / LATENCY RELATIONSHIPS SYMBOL PARAMETER -6 -7 UNITS

— ClockCycleTime 6 7 ns

— OperatingFrequency 166 143 MHz

tccD READ/WRITEcommandtoREAD/WRITEcommand 1 1 cycle

tckeD CKEtoclockdisableorpower-downentrymode 1 1 cycle

tpeD CKEtoclockenableorpower-downexitsetupmode 1 1 cycle

tDqD DQMtoinputdatadelay 0 0 cycle

tDqm DQMtodatamaskduringWRITEs 0 0 cycle

tDqz DQMtodatahigh-impedanceduringREADs 2 2 cycle

tDwD WRITEcommandtoinputdatadelay 0 0 cycle

tDal Data-intoACTIVEcommand 5 5 cycle

tDpl Data-intoPRECHARGEcommand 2 2 cycle

tbDl Lastdata-intoburstSTOPcommand 1 1 cycle

tcDl Lastdata-intonewREAD/WRITEcommand 1 1 cycle

trDl Lastdata-intoPRECHARGEcommand 2 2 cycle

tmrD LOADMODEREGISTERcommand 2 2 cycle toACTIVEorREFRESHcommand

troh Data-outtohigh-impedancefrom CL=3 3 3 cycle PRECHARGEcommand CL=2 2 2 cycle


IS42S16400

FUNCTIONAL DESCRIPTIONThe64MbSDRAMs(1Megx16x4banks)arequad-bankDRAMswhichoperateat3.3Vandincludeasynchronousinterface (all signals are registered on the positive edge of theclocksignal,CLK).Eachofthe16,777,216-bitbanksisorganizedas4,096rowsby256columnsby16bits.

ReadandwriteaccessestotheSDRAMareburstoriented;accesses start at a selected location and continue for a programmed number of locations in a programmed sequence. Accesses begin with the registration of an AC-TIVEcommandwhichisthenfollowedbyaREADorWRITEcommand.TheaddressbitsregisteredcoincidentwiththeACTIVEcommandareusedtoselectthebankandrowtobe accessed (BA0andBA1selectthebank,A0-A11selecttherow).Theaddressbits(A0-A7) registered coincident with the READorWRITEcommandareusedtoselectthestartingcolumn location for the burst access.

Prior to normal operation, the SDRAM must be initial-ized.Thefollowingsectionsprovidedetailedinformationcovering device initialization, register definition, command descriptions and device operation.

InitializationSDRAMs must be powered up and initialized in a predefined manner.

The64MSDRAMisinitializedafterthepowerisappliedtoVDDandVDDq (simultaneously), and the clock is stable withDQMHighandCKEHigh.

A 100µs delay is required prior to issuing any command other than a COMMANDINHIBIT or a NOP.TheCOMMANDINHIBITorNOPmaybeappliedduringthe100µsperiodandcontinue should at least through the end of the period.

WithatleastoneCOMMANDINHIBITorNOPcommandhavingbeenapplied,aPRECHARGEcommandshouldbe applied once the 100µs delay has been satisfied. All banksmustbeprecharged.Thiswill leaveallbanksinan idle state, afterwhichatleasttwoAUTOREFRESH cycles must be performed. After the AUTOREFRESH cycles are complete, the SDRAM is then ready for mode registerprogramming.

The mode register should be loaded prior to applyingany operational command because it will power up in an unknownstate.AftertheLoadModeRegistercommand,at least twoNOPcommandsmustbeassertedprior toany command.


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IS42S16400

REGISTER DEFINITION

Mode RegisterThemode register isused todefine thespecificmodeofoperationof theSDRAM.Thisdefinition includestheselection of a burst length, a burst type, a CAS latency, an operating mode and a write burst mode, as shown in MODEREGISTERDEFINITION.

ThemoderegisterisprogrammedviatheLOADMODEREGISTERcommandandwillretainthestoredinformationuntil it is programmed again or the device loses power.

Mode register bits M0-M2 specify the burst length, M3 specifies the type of burst (sequential or interleaved), M4- M6 specify the CAS latency, M7 and M8 specify the operating mode,M9specifiestheWRITEburstmode,andM10andM11 are reserved for future use.

Themode registermustbe loadedwhenallbanksareidle, and the controller must wait the specified time before initiatingthesubsequentoperation.Violatingeitheroftheserequirements will result in unspecified operation.

MODE REGISTER DEFINITION

Latency Mode

M6 M5 M4 CAS Latency

0 0 0 Reserved 0 0 1 Reserved 0 1 0 2 0 1 1 3 1 0 0 Reserved 1 0 1 Reserved 1 1 0 Reserved 1 1 1 Reserved

1. To ensure compatibility with future devices,should program M11, M10 = "0, 0"

Write Burst Mode

M9 Mode

0 Programmed Burst Length

1 Single Location Access

Operating Mode

M8 M7 M6-M0 Mode

0 0 Defined Standard Operation — — — All Other States Reserved

Burst Type

M3 Type

0 Sequential 1 Interleaved

Burst Length

M2 M1 M0 M3=0 M3=1

0 0 0 1 1 0 0 1 2 2 0 1 0 4 4 0 1 1 8 8 1 0 0 Reserved Reserved 1 0 1 Reserved Reserved 1 1 0 Reserved Reserved 1 1 1 Full Page Reserved

Reserved

Address Bus

Mode Register (Mx)

A11 A10 A9 A8 A7 A6 A5 A4 A3 A2 A1 A0

(1)


IS42S16400

BURST DEFINITION

Burst Starting Column Order of Accesses Within a Burst

Length Address Type = Sequential Type = Interleaved

A0

2 0 0-1 0-1

1 1-0 1-0

A1 A0

0 0 0-1-2-3 0-1-2-3

4 0 1 1-2-3-0 1-0-3-2

1 0 2-3-0-1 2-3-0-1

1 1 3-0-1-2 3-2-1-0

A2 A1 A0

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

8 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

Full n=A0-A7 Cn,Cn+1,Cn+2 NotSupported Page Cn+3,Cn+4... (y) (location 0-y) …Cn - 1, Cn…

Burst LengthReadandwriteaccessestotheSDRAMareburstoriented,with the burst length being programmable, as shown in MODEREGISTERDEFINITION.Theburstlengthdeter-mines the maximum number of column locations that can beaccessedforagivenREADorWRITEcommand.Burstlengths of 1, 2, 4 or 8 locations are available for both the sequential and the interleaved burst types, and a full-page burst is available for the sequential type.The full-pageburstisusedinconjunctionwiththeBURSTTERMINATEcommand to generate arbitrary burst lengths.

Reservedstatesshouldnotbeused,asunknownoperationor incompatibility with future versions may result.

WhenaREADorWRITEcommandisissued,ablockofcolumns equal to the burst length is effectively selected. All accesses for that burst take place within this block, mean-

ing that the burst will wrap within the block if a boundary isreached.TheblockisuniquelyselectedbyA1-A7(x16)whentheburstlengthissettotwo;byA2-A7(x16)whentheburstlengthissettofour;andbyA3-A7(x16)whentheburstlengthissettoeight.Theremaining(leastsignificant)address bit(s) is (are) used to select the starting location withintheblock.Full-pageburstswrapwithinthepageifthe boundary is reached.

Burst TypeAccesses within a given burst may be programmed to be eithersequentialorinterleaved;thisisreferredtoastheburst type and is selected via bit M3.

Theorderingofaccesseswithinaburstisdeterminedbythe burst length, the burst type and the starting column address,asshowninBURSTDEFINITIONtable.


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IS42S16400

DON'T CARE

UNDEFINED

CLK

COMMAND

DQ

READ NOP NOP NOP

CAS Latency - 3

tAC

tOH

DOUT

T0 T1 T2 T3 T4

tLZ

CLK

COMMAND

DQ

READ NOP NOP

CAS Latency - 2

tAC

tOH

DOUT

T0 T1 T2 T3

tLZ

CAS Latency

CAS LatencyTheCAS latency is thedelay, inclockcycles,betweenthe registrationofaREADcommandandtheavailabilityofthefirstpieceofoutputdata.Thelatencycanbesettotwoorthree clocks.

IfaREADcommandisregisteredatclockedgen,andthe latency is m clocks, the data will be available by clock edge n + m.TheDQswillstartdrivingasaresultoftheclock edge one cycle earlier (n + m - 1), and provided that the relevant access times are met, the data will be valid by clock edge n + m.Forexample,assumingthattheclockcycle time is such that all relevant access times are met, ifaREADcommandisregisteredatT0andthelatencyisprogrammedto twoclocks, theDQswillstartdrivingafterT1andthedatawillbevalidbyT2,asshowninCASLatencydiagrams.TheAllowable Operating Frequency table indicates the operating frequencies at which each CAS latency setting can be used.

Reservedstatesshouldnotbeusedasunknownoperationor incompatibility with future versions may result.

CAS LatencyAllowable Operating Frequency (MHz)

Speed CAS Latency = 2 CAS Latency = 3

6 133 166

7 133 143

Operating ModeThenormaloperatingmodeisselectedbysettingM7andM8tozero;theothercombinationsofvaluesforM7andM8arereservedforfutureuseand/ortestmodes.TheprogrammedburstlengthappliestobothREADandWRITEbursts.

Testmodesandreservedstatesshouldnotbeusedbe-cause unknown operation or incompatibility with future versions may result.

Write Burst ModeWhenM9=0,theburstlengthprogrammedviaM0-M2appliestobothREADandWRITEbursts;whenM9=1,theprogrammedburstlengthappliestoREADbursts,butwrite accesses are single-location (nonburst) accesses.


IS42S16400

CLK

CKEHIGH - Z

ROW ADDRESS

BANK ADDRESS

CS

RAS

CAS

WE

A0-A11

BA0, BA1

Activating Specific Row Within Specific Bank

DON'T CARE

CLK

COMMAND ACTIVE NOP NOP

tRCD

T0 T1 T2 T3 T4

READ orWRITE

OPERATION

BANK/ROW ACTIVATIONBeforeanyREADorWRITEcommandscanbe issuedtoabankwithintheSDRAM,arowinthatbankmustbe“opened.”ThisisaccomplishedviatheACTIVEcommand,which selects both the bank and the row to be activated (see ActivatingSpecificRowWithinSpecificBank).

After opening a row (issuinganACTIVEcommand),aREADorWRITEcommandmaybeissuedtothatrow,subjecttothe trcD specification. Minimum trcD should be divided by the clock period and rounded up to the next whole number to determine the earliest clock edge after the ACTIVEcommandonwhichaREADorWRITEcommandcanbeentered.Forexample,atrcD specification of 20ns with a 125 MHz clock (8ns period) results in 2.5 clocks, rounded to3.Thisisreflectedinthefollowingexample,whichcov-ersanycasewhere2<[trcD (MIN)/tck] ≤3.(Thesameprocedure is used to convert other specification limits from time units to clock cycles).

AsubsequentACTIVEcommandtoadifferentrowinthesame bank can only be issued after the previous active rowhasbeen“closed”(precharged).TheminimumtimeintervalbetweensuccessiveACTIVEcommands to thesame bank is defined by trc.

AsubsequentACTIVEcommandtoanotherbankcanbeissued while the first bank is being accessed, which results inareductionoftotalrow-accessoverhead.TheminimumtimeintervalbetweensuccessiveACTIVEcommandstodifferent banks is defined by trrD.

Example: Meeting tRCD (MIN) when 2 < [tRCD (min)/tCK] ≤ 3


01/30/08

IS42S16400

CLK

CKEHIGH-Z

COLUMN ADDRESS

AUTO PRECHARGE

NO PRECHARGE

CS

RAS

CAS

WE

A0-A7

A10

BA0, BA1 BANK ADDRESS

A8, A9, A11

READ COMMANDREADSREAD bursts are initiated with a READ command, asshownintheREADCOMMANDdiagram.

ThestartingcolumnandbankaddressesareprovidedwiththeREADcommand,andautoprechargeiseitherenabledordisabled for that burst access. If auto precharge is enabled, the row being accessed is precharged at the completion of theburst.ForthegenericREADcommandsusedinthefol-lowing illustrations, auto precharge is disabled.

DuringREADbursts,thevaliddata-outelementfromthestarting column address will be available following the CASlatencyaftertheREADcommand.Eachsubsequentdata-out element will be valid by the next positive clock edge.TheCASLatencydiagramshowsgeneral timing for each possible CAS latency setting.

Uponcompletionofaburst,assumingnoothercommandshavebeeninitiated,theDQswillgoHigh-Z.Afull-pageburstwill continue until terminated. (At the end of the page, it will wrap to column 0 and continue.)

DatafromanyREADburstmaybetruncatedwithasub-sequentREADcommand,anddatafromafixed-lengthREADburstmaybeimmediatelyfollowedbydatafromaREADcommand.Ineithercase,acontinuousflowofdatacanbemaintained.Thefirstdataelementfromthenewburst follows either the last element of a completed burst or the last desired data element of a longer burst which is being truncated.

ThenewREADcommandshouldbeissuedx cycles before the clock edge at which the last desired data element is valid, where x equalstheCASlatencyminusone.ThisisshowninConsecutiveREADBurstsforCASlatenciesoftwoandthree;dataelementn +3iseitherthelastofaburstoffourorthelastdesiredofalongerburst.The64MbSDRAMusesapipelinedarchitectureandthereforedoesnot require the 2n rule associated with a prefetch architec-ture.AREADcommandcanbeinitiatedonanyclockcyclefollowingapreviousREADcommand.Full-speedrandomread accesses can be performed to the same bank, as showninRandomREADAccesses,oreachsubsequentREADmaybeperformedtoadifferentbank.

DatafromanyREADburstmaybetruncatedwithasub-sequent WRITE command, and data from a fixed-lengthREADburstmaybeimmediatelyfollowedbydatafromaWRITEcommand(subjecttobusturnaroundlimitations).TheWRITEburstmaybeinitiatedontheclockedgeim-mediately following the last (or last desired) data element fromtheREADburst,providedthatI/Ocontentioncanbeavoided. In a given system design, there may be a pos-sibilitythatthedevicedrivingtheinputdatawillgoLow-ZbeforetheSDRAMDQsgoHigh-Z.Inthiscase,atleasta single-cycle delay should occur between the last read dataandtheWRITEcommand.

TheDQMinputisusedtoavoidI/Ocontention,asshowninFiguresRW1andRW2.TheDQMsignalmustbeas-serted (HIGH)at least threeclocksprior to theWRITEcommand(DQMlatencyistwoclocksforoutputbuffers)tosuppressdata-out fromtheREAD.Once theWRITEcommandisregistered,theDQswillgoHigh-Z(orremainHigh-Z),regardlessofthestateoftheDQMsignal,providedtheDQMwasactiveontheclockjustpriortotheWRITEcommandthattruncatedtheREADcommand.Ifnot,thesecondWRITEwillbeaninvalidWRITE.Forexample,ifDQMwasLOWduringT4inFigureRW2,thentheWRITEsatT5andT7wouldbevalid,whiletheWRITEatT6wouldbe invalid.

TheDQMsignalmustbede-assertedpriortotheWRITEcommand(DQMlatencyiszeroclocksforinputbuffers)to ensure that the written data is not masked.

Afixed-lengthREADburstmaybefollowedby,ortruncatedwith, a PRECHARGE command to the same bank (provided that auto precharge was not activated), and a full-page burst maybetruncatedwithaPRECHARGEcommandtothesamebank.ThePRECHARGEcommandshouldbeissuedx cycles before the clock edge at which the last desired data element is valid, where x equals the CAS latency minusone.ThisisshownintheREADtoPRECHARGE


IS42S16400

DON'T CARE

UNDEFINED

CLK

COMMAND

DQ

READ NOP NOP NOP

CAS Latency - 3

tAC

tOH

DOUT

T0 T1 T2 T3 T4

tLZ

CLK

COMMAND

DQ

READ NOP NOP

CAS Latency - 2

tAC

tOH

DOUT

T0 T1 T2 T3

tLZ

CAS Latency

diagramforeachpossibleCASlatency;dataelementn +3 is either the last of a burst of four or the last desired of alongerburst.FollowingthePRECHARGEcommand,asubsequent command to the same bank cannot be issued until trp is met. Note that part of the row precharge time is hidden during the access of the last data element(s).

In the case of a fixed-length burst being executed to completion, a PRECHARGE command issued at theoptimum time (as described above) provides the same operation that would result from the same fixed-length burstwithautoprecharge.ThedisadvantageofthePRE-CHARGEcommandisthatitrequiresthatthecommandand address buses be available at the appropriate time to issuethecommand;theadvantageofthePRECHARGEcommand is that it can be used to truncate fixed-length or full-page bursts.

Full-pageREADburstscanbetruncatedwiththeBURSTTERMINATE command, and fixed-length READ burstsmaybetruncatedwithaBURSTTERMINATEcommand,providedthatautoprechargewasnotactivated.TheBURSTTERMINATEcommandshouldbeissuedx cycles before the clock edge at which the last desired data element is valid, where x equalstheCASlatencyminusone.ThisisshownintheREADBurstTerminationdiagramforeachpossibleCASlatency;dataelementn +3isthelastdesireddata element of a longer burst.


01/30/08

IS42S16400

DON'T CARE

CLK

COMMAND

ADDRESS

DQ

T0 T1 T2 T3 T4 T5 T6

READ NOP NOP NOP READ NOP NOP

DOUT n DOUT n+1 DOUT n+2 DOUT n+3 DOUT b

BANK,COL n

BANK,COL b

CAS Latency - 2

x = 1 cycle

DON'T CARE

CLK

COMMAND

ADDRESS

DQ

T0 T1 T2 T3 T4 T5 T6 T7

READ NOP NOP NOP READ NOP NOP NOP

DOUT n DOUT n+1 DOUT n+2 DOUT n+3 DOUT b

BANK,COL n

BANK,COL b

CAS Latency - 3

x = 2 cycles

Consecutive READ Bursts


IS42S16400

DON'T CARE

CLK

COMMAND

ADDRESS

DQ

T0 T1 T2 T3 T4 T5

READ READ READ READ NOP NOP

DOUT n DOUT b DOUT m DOUT x

BANK,COL n

BANK,COL b

CAS Latency - 2

BANK,COL m

BANK,COL x

DON'T CARE

CLK

COMMAND

ADDRESS

DQ

T0 T1 T2 T3 T4 T5 T6

READ READ READ READ NOP NOP NOP

DOUT n DOUT b DOUT m DOUT x

BANK,COL n

BANK,COL b

CAS Latency - 3

BANK,COL m

BANK,COL x

Random READ Accesses


01/30/08

IS42S16400

DON'T CARE

CLK

DQM

COMMAND

ADDRESS

DQ

T0 T1 T2 T3 T4 T5

READ NOP NOP NOP NOP WRITE

BANK,COL n

BANK,COL b

DOUT n DIN b

tDS

tHZ

CAS Latency - 3

RW1 - READ to WRITE

RW2 - READ to WRITE

DON'T CARE

CLK

DQM

COMMAND

ADDRESS

DQ

T0 T1 T2 T3 T4 T5 T6

READ NOP NOP NOP NOP NOP WRITE

BANK,COL n

DIN b

tDS

tHZ

BANK,COL b

CAS Latency - 2

DOUT n DOUT n+1 DOUT n+2


IS42S16400

DON'T CARE

CLK

COMMAND

ADDRESS

DQ

T0 T1 T2 T3 T4 T5 T6 T7

READ NOP NOP NOP NOP NOP ACTIVE

DOUT n DOUT n+1 DOUT n+2 DOUT n+3

BANK a,COL n

BANK a,ROW

BANK(a or all)

CAS Latency - 2

x = 1 cycle

tRP

PRECHARGE

DON'T CARE

CLK

COMMAND

ADDRESS

DQ

T0 T1 T2 T3 T4 T5 T6 T7

READ NOP NOP NOP NOP NOP ACTIVE


BANK,COL n

BANK,COL b

CAS Latency - 3

x = 2 cycles

tRP

BANK a,ROW

PRECHARGE

READ to PRECHARGE


01/30/08

IS42S16400

DON'T CARE

CLK

COMMAND

ADDRESS

DQ

T0 T1 T2 T3 T4 T5 T6

READ NOP NOP NOP NOP NOP


BANK a,COL n

CAS Latency - 2

x = 1 cycle

BURSTTERMINATE

DON'T CARE

CLK

COMMAND

ADDRESS

DQ

T0 T1 T2 T3 T4 T5 T6 T7

READ NOP NOP NOP NOP NOP NOP


BANK,COL n

CAS Latency - 3

x = 2 cycles

BURSTTERMINATE

READ Burst Termination


IS42S16400

CLK

CKEHIGH - Z

COLUMN ADDRESS

AUTO PRECHARGE

BANK ADDRESS

CS

RAS

CAS

WE

A0-A7

A10

BA0, BA1

NO PRECHARGE

A8, A9, A11

WRITE Command

ThestartingcolumnandbankaddressesareprovidedwiththeWRITEcommand,andautoprechargeiseitherenabledor disabled for that access. If auto precharge is enabled, the row being accessed is precharged at the completion of theburst.ForthegenericWRITEcommandsusedinthefollowing illustrations, auto precharge is disabled.

DuringWRITEbursts,thefirstvaliddata-in element will be registered coincident with the WRITEcommand. Subsequent data elements will be registered on each successive posi-tiveclockedge.Uponcompletionofafixed-lengthburst,assuming no other commands have been initiated, the DQswillremainHigh-Zandanyadditionalinputdatawillbeignored(seeWRITEBurst).Afull-pageburstwillcon-tinue until terminated. (At the end of the page, it will wrap to column 0 and continue.)

DataforanyWRITEburstmaybetruncatedwithasubse-quentWRITEcommand,anddataforafixed-lengthWRITEburstmaybe immediately followedbydata foraWRITEcommand.ThenewWRITEcommandcanbe issuedonanyclockfollowingthepreviousWRITEcommand,andthedata provided coincident with the new command applies to the new command.

AnexampleisshowninWRITEtoWRITEdiagram.Datan +1iseitherthelastofaburstoftwoorthelastdesiredof a longer burst.The 64Mb SDRAM uses a pipelinedarchitecture and therefore does not require the 2n rule as-sociatedwithaprefetcharchitecture.AWRITEcommandcan be initiated on any clock cycle following a previous WRITEcommand.Full-speedrandomwriteaccesseswithina page can be performed to the same bank, as shown in RandomWRITECycles,oreachsubsequentWRITEmaybe performed to a different bank.

DataforanyWRITEburstmaybetruncatedwithasubse-quentREADcommand,anddataforafixed-lengthWRITEburstmaybeimmediatelyfollowedbyasubsequentREADcommand.OncetheREADcommandisregistered,thedatainputswillbeignored,andWRITEswillnotbeex-ecuted.AnexampleisshowninWRITEtoREAD.Datan +1iseitherthelastofaburstoftwoorthelastdesiredof a longer burst.

Data for a fixed-length WRITE burst may be followedby,or truncatedwith,aPRECHARGEcommandto thesame bank (provided that auto precharge was not acti-vated), anda full-pageWRITEburstmaybe truncatedwithaPRECHARGEcommand to thesamebank.ThePRECHARGEcommandshouldbeissuedtwr after the clock edge at which the last desired input data element isregistered.Theautoprechargemoderequiresatwr of at least one clock plus time, regardless of frequency. In addition,whentruncatingaWRITEburst,theDQMsignalmust be used to mask input data for the clock edge prior to,andtheclockedgecoincidentwith,thePRECHARGEcommand.AnexampleisshownintheWRITEtoPRE-CHARGEdiagram.Datan+1iseitherthelastofaburstoftwoorthelastdesiredofalongerburst.FollowingthePRECHARGEcommand,asubsequentcommandtothesame bank cannot be issued until trp is met.

In the case of a fixed-length burst being executed to comple-tion,aPRECHARGEcommand issuedat theoptimumtime (as described above) provides the same operation that would result from the same fixed-length burst with auto precharge.ThedisadvantageofthePRECHARGE command is that it requires that the command and address buses be availableattheappropriatetimetoissuethecommand;theadvantageofthePRECHARGEcommandisthatitcanbeused to truncate fixed-length or full-page bursts.

Fixed-lengthorfull-pageWRITEburstscanbetruncatedwiththeBURSTTERMINATEcommand.Whentruncat-ingaWRITEburst,theinputdataappliedcoincidentwiththeBURSTTERMINATEcommandwillbeignored.Thelastdatawritten(providedthatDQMisLOWatthattime)will be the input data applied one clock previous to the BURSTTERMINATEcommand.ThisisshowninWRITEBurstTermination,wheredatan is the last desired data element of a longer burst.

WRITEsWRITEburstsareinitiatedwithaWRITEcommand,asshowninWRITECommanddiagram.


01/30/08

IS42S16400

CLK

COMMAND

ADDRESS

DQ

T0 T1 T2 T3

WRITE NOP NOP NOP

DIN n DIN n+1

BANK,COL n

DON'T CARE

CLK

COMMAND

ADDRESS

DQ

T0 T1 T2

WRITE NOP WRITE

DIN n DIN n+1 DIN b

BANK,COL n

BANK,COL b

DON'T CARE

WRITE Burst

WRITE to WRITE

CLK

COMMAND

ADDRESS

DQ

T0 T1 T2 T3

WRITE WRITE WRITE WRITE

DIN n DIN b DIN m DIN x

BANK,COL n

BANK,COL b

BANK,COL m

BANK,COL x

Random WRITE Cycles


IS42S16400

DON'T CARE

CLK

COMMAND

ADDRESS

DQ

T0 T1 T2 T3 T4 T5

WRITE NOP READ NOP NOP NOP

DIN n DIN n+1 DOUT b DOUT b+1

BANK,COL n

BANK,COL b

CAS Latency - 2

WRITE to READ

WP1 - WRITE to PRECHARGE

DON'T CARE

CLK

DQM

COMMAND

ADDRESS

DQ

T0 T1 T2 T3 T4 T5 T6

WRITE NOP NOP ACTIVE NOP NOP

BANK a,COL n

BANK a,ROW

BANK(a or all)

tWR

tRP

PRECHARGE

DIN n DIN n+1

CAS Latency - 2


01/30/08

IS42S16400

CLK

COMMAND

ADDRESS

DQ

T0 T1 T2

WRITE

DIN n (DATA)

BANK,COL n

DON'T CARE

(ADDRESS)

BURSTTERMINATE

NEXTCOMMAND

WRITE Burst Termination

DON'T CARE

CLK

DQM

COMMAND

ADDRESS

DQ

T0 T1 T2 T3 T4 T5 T6

WRITE NOP NOP NOP ACTIVE NOP

BANK a,COL n

BANK a,ROW

BANK(a or all)

tWR

tRP

PRECHARGE

DIN n DIN n+1

CAS Latency - 3

WP2 - WRITE to PRECHARGE


IS42S16400

CLK

CKEHIGH - Z

ALL BANKS

BANK SELECT

BANK ADDRESS

CS

RAS

CAS

WE

A0-A9, A11

A10

BA0, BA1

DON'T CARE

CLK

CKE

COMMAND NOP NOP ACTIVE

≥ tCKStCKS

All banks idle

Enter power-down mode Exit power-down mode

tRCD

tRAS

tRC

Input buffers gated off

PRECHARGE Command

POWER-DOWN

POWER-DOWNPower-downoccursifCKEisregisteredLOWcoincidentwithaNOPorCOMMANDINHIBITwhennoaccessesare in progress. If power-down occurs when all banks are idle,thismodeisreferredtoasprechargepower-down;if power-down occurs when there is a row active in either bank, this mode is referred to as active power-down. Entering power-down deactivates the input and outputbuffers,excludingCKE,formaximumpowersavingswhileinstandby.Thedevicemaynotremaininthepower-downstate longer than the refresh period (64ms) since no refresh operations are performed in this mode.

Thepower-downstateisexitedbyregisteringaNOPorCOMMANDINHIBITandCKEHIGHatthedesiredclockedge (meeting tcks). See figure below.

PRECHARGEThePRECHARGEcommand(seefigure)isusedtodeac-tivate the open row in a particular bank or the open row in allbanks.Thebank(s)willbeavailableforasubsequentrowaccess some specified time (trp)afterthePRECHARGEcommand is issued. Input A10 determines whether one or all banks are to be precharged, and in the case where only onebankistobeprecharged,inputsBA0,BA1selectthebank.Whenallbanksaretobeprecharged,inputsBA0,BA1aretreatedas“Don’tCare.”Onceabankhasbeenprecharged, it is in the idle state and must be activated priortoanyREADorWRITEcommandsbeingissuedtothat bank.


01/30/08

IS42S16400

DON'T CARE

CLK

CKE

COMMAND

ADDRESS

DQ

T0 T1 T2 T3 T4 T5

NOP WRITE NOP NOP

BANK a,COL n

DIN n DIN n+1 DIN n+2

INTERNALCLOCK

DON'T CARE

CLK

CKE

COMMAND

ADDRESS

DQ

T0 T1 T2 T3 T4 T5 T6

READ NOP NOP NOP NOP NOP

BANK a,COL n


INTERNALCLOCK

CLOCK SUSPENDClock suspend mode occurs when a column access/burst is inprogressandCKEisregisteredLOW.In theclocksuspendmode,theinternalclockisdeactivated,“freezing”the synchronous logic.

ForeachpositiveclockedgeonwhichCKEissampledLOW,thenextinternalpositiveclockedgeissuspended.Any command or data present on the input pins at the time

ofasuspendedinternalclockedgeisignored;anydatapresentontheDQpinsremainsdriven;andburstcountersare not incremented, as long as the clock is suspended. (See following examples.)

ClocksuspendmodeisexitedbyregisteringCKEHIGH;the internal clock and related operation will resume on the subsequent positive clock edge.

Clock Suspend During WRITE Burst

Clock Suspend During READ Burst


IS42S16400

DON'T CARE

CLK

COMMAND

BANK n

BANK m

ADDRESS

DQ

T0 T1 T2 T3 T4 T5 T6 T7

NOP NOP NOP NOP NOP NOP

DOUT a DOUT a+1 DOUT b DOUT b+1

BANK n,COL a

BANK m,COL b

CAS Latency - 3 (BANK n)

CAS Latency - 3 (BANK m)

tRP - BANK n tRP - BANK m

READ - APBANK n

READ - APBANK m

Page Active READ with Burst of 4 Interrupt Burst, Precharge Idle

Page Active READ with Burst of 4 Precharge

Internal States

DON'T CARE

CLK

COMMAND

BANK n

BANK m

ADDRESS

DQM

DQ

T0 T1 T2 T3 T4 T5 T6 T7


DOUT a DIN b DIN b+1 DIN b+2 DIN b+3

BANK n,COL a

BANK m,COL b

CAS Latency - 3 (BANK n)

tRP - BANK n tRP - BANK m

WRITE - APBANK n

WRITE - APBANK m

READ with Burst of 4 Interrupt Burst, Precharge Idle

Page Active WRITE with Burst of 4 Write-Back

Internal States Page Active

BURST READ/SINGLE WRITETheburstread/singlewritemodeisenteredbyprogrammingthe write burst mode bit (M9) in the mode register to a logic 1. In this mode, all WRITE commands result in the access of a single column location (burst of one), regardless of theprogrammedburstlength.READcommandsaccess columns according to the programmed burst length and sequence,justasinthenormalmodeofoperation(M9= 0).

CONCURRENT AUTO PRECHARGEAnaccesscommand(READorWRITE)toanotherbankwhile an access command with auto precharge enabled is executingisnotallowedbySDRAMs,unlesstheSDRAMsupports CONCURRENT AUTO PRECHARGE. ISSI

SDRAMssupportCONCURRENTAUTOPRECHARGE.FourcaseswhereCONCURRENTAUTOPRECHARGEoccurs are defined below.

READ with Auto Precharge1.InterruptedbyaREAD(withorwithoutautoprecharge):

AREADtobankmwill interruptaREADonbankn,CAS latency later.The PRECHARGE to bank n willbeginwhentheREADtobankmisregistered.

2.InterruptedbyaWRITE(withorwithoutautoprecharge):AWRITEtobankmwillinterruptaREADonbanknwhenregistered.DQMshouldbeusedtwoclockspriortotheWRITEcommandtopreventbuscontention.ThePRECHARGEtobanknwillbeginwhentheWRITEtobank m is registered.

Fig CAP 1 - READ With Auto Precharge interrupted by a READ

Fig CAP 2 - READ With Auto Precharge interrupted by a WRITE


01/30/08

IS42S16400

DON'T CARE

CLK

COMMAND

BANK n

BANK m

ADDRESS

DQ

T0 T1 T2 T3 T4 T5 T6 T7


DIN a DIN a+1 DOUT b DOUT b+1

BANK n,COL a

BANK m,COL b

CAS Latency - 3 (BANK m)

tRP - BANK ntRP - BANK m

WRITE - APBANK n

READ - APBANK m

Page Active WRITE with Burst of 4 Interrupt Burst, Write-Back Precharge

Page Active READ with Burst of 4 Precharge

Internal States tWR - BANK n

DON'T CARE

CLK

COMMAND

BANK n

BANK m

ADDRESS

DQ

T0 T1 T2 T3 T4 T5 T6 T7


BANK n,COL a

BANK m,COL b

tRP - BANK ntRP - BANK m

WRITE - APBANK n

WRITE - APBANK m

Page Active WRITE with Burst of 4 Interrupt Burst, Write-Back Precharge

Page Active WRITE with Burst of 4 Write-Back

Internal States tWR - BANK n

DIN a DIN a+1 DIN a+2 DIN b DIN b+1 DIN b+2 DIN b+3

WRITE with Auto Precharge3.InterruptedbyaREAD(withorwithoutautoprecharge):

AREADtobankmwill interruptaWRITEonbanknwhen registered, with the data-out appearing CAS latency later.ThePRECHARGEtobanknwillbeginaftertwr is met, where twrbeginswhentheREADtobankmisregistered.ThelastvalidWRITE to bank n will be data-in registeredoneclockpriortotheREADtobankm.

4.InterruptedbyaWRITE(withorwithoutautoprecharge):AWRITE to bank m will interrupt a WRITE on bank n when registered.ThePRECHARGEtobanknwillbeginaftertwr is met, where twrbeginswhentheWRITEtobankmisregistered.ThelastvaliddataWRITEtobanknwillbedataregisteredoneclockpriortoaWRITEtobank m.

Fig CAP 3 - WRITE With Auto Precharge interrupted by a READ

Fig CAP 4 - WRITE With Auto Precharge interrupted by a WRITE


IS42S16400

INITIALIzE AND LOAD MODE REGISTER(1)

DON'T CARE

CLK

CKE

COMMAND

DQM/DQML, DQMH

A0-A9, A11

A10

BA0, BA1

DQ

tCH tCLtCK

tCMH tCMS tCMH tCMS tCMH tCMS

tCKS tCKH

T0 T1 Tn+1 To+1 Tp+1 Tp+2 Tp+3

tMRDtRCtRCtRP

ROW

ROW

BANK

tAS tAH

tAS tAH

CODE

CODEALL BANKS

SINGLE BANK

ALL BANKS

AUTOREFRESH

AUTOREFRESH

Load MODEREGISTER

T = 100µs Min.

Power-up: VCC

and CLK stablePrechargeall banks

AUTO REFRESH Program MODE REGISTER

NOP PRECHARGE NOP NOP NOP ACTIVE

T

(2, 3, 4)AUTO REFRESH

At least 2 Auto-Refresh Commands

Notes:1. If CSisHighatclockHightime,allcommandsappliedareNOP.2.TheModeregistermaybeloadedpriortotheAuto-Refreshcyclesifdesired.3.JEDECandPC100specifythreeclocks.4.OutputsareguaranteedHigh-Zafterthecommandisissued.


01/30/08

IS42S16400

POWER-DOWN MODE CYCLE

CAS latency = 2, 3

DON'T CARE

CLK

CKE

COMMAND

DQM/DQML, DQMH

A0-A9, A11

A10

BA0, BA1

DQ

tAS tAH

BANK

tCHtCLtCK

tCMS tCMH

tCKS tCKH

PRECHARGE NOP NOP NOP ACTIVE

ALL BANKS

SINGLE BANK

ROW

ROW

BANK

tCKStCKS

Precharge allactive banks

All banks idleTwo clock cycles Input buffers gatedoff while in

power-down modeAll banks idle, enterpower-down mode Exit power-down mode

T0 T1 T2 Tn+1 Tn+2

High-Z


IS42S16400

CLOCK SUSPEND MODE

Notes:1. CAS latency = 3, burst length = 22. A8, A9, and A11="Don'tCare"

DON'T CARE

CLK

CKE

COMMAND

DQM/DQML, DQMH

A0-A9, A11

A10

BA0, BA1

DQ

tCMS tCMH

tAS tAH

tAS tAH

tAS tAH

tCHtCLtCK

tCMS tCMH

tCKS tCKH

COLUMN m(2)

T0 T1 T2 T3 T4 T5 T6 T7 T8 T9

READ NOP NOP NOP NOP NOP WRITE NOP

tCKS tCKH

BANK BANK

COLUMN n(2)

tAC tAC

tOH

tHZ

DOUT m DOUT m+1

tLZ

UNDEFINED

DOUT e+1

tDS tDH

DOUT e


01/30/08

IS42S16400

AUTO-REFRESH CYCLE

CAS latency = 2, 3

tRP tRC tRC

DON'T CARE

CLK

CKE

COMMAND

DQM/DQML, DQMH

A0-A9, A11

A10

BA0, BA1

DQ

tAS tAH

tCHtCLtCK

tCMS tCMH

tCKS tCKH

T0 T1 T2 Tn+1 To+1

ALL BANKS

SINGLE BANK

BANK(s)

ROW

ROW

BANK

High-Z

PRECHARGE NOP NOP NOP ACTIVEAutoRefresh

AutoRefresh


IS42S16400

SELF-REFRESH CYCLE

CAS latency = 2, 3

CLK

CKE

COMMAND

DQM/DQML, DQMH

A0-A9, A11

A10

BA0, BA1

DQ

tAS tAH

BANK

tCLtCHtCK

tCMS tCMH

tCKS tCKH

ALL BANKS

SINGLE BANK

tCKS

Precharge allactive banks

CLK stable prior to exitingself refresh mode

Enter selfrefresh mode

Exit self refresh mode(Restart refresh time base)

T0 T1 T2 Tn+1 To+1 To+2

High-Z

AutoRefresh

AutoRefreshPRECHARGE NOP NOP NOP

tCKS

≥ tRAS

tRP tXSR

DON'T CARE


01/30/08

IS42S16400

READ WITHOUT AUTO PRECHARGE

DON'T CARE

UNDEFINED

CLK

CKE

COMMAND

DQM/DQML, DQMH

A0-A9, A11

A10

BA0, BA1

DQ

tCMS tCMH

ACTIVE NOP READ NOP NOP NOP PRECHARGE NOP ACTIVE

tAS tAH

tAS tAH

tAS tAH

ROW

ROW

BANK

COLUMN m(2)

tCHtCLtCK

tCMS tCMH

tCKS tCKH

BANK

tRCD CAS Latency

tAC tAC tAC tAC

tOH

tHZ

tOH

DOUT m

tOH

DOUT m+1

tOH

DOUT m+2 DOUT m+3

T0 T1 T2 T3 T4 T5 T6 T7 T8

DISABLE AUTO PRECHARGE

ROW

ROW

BANK

tLZ

tRAS

tRC

tRP

ALL BANKS

SINGLE BANK

BANK



IS42S16400

READ WITH AUTO PRECHARGE

DON'T CARE

UNDEFINED

CLK

CKE

COMMAND

DQM/DQML, DQMH

A0-A9, A11

A10

BA0, BA1

DQ

tCMS tCMH

ACTIVE NOP READ NOP NOP NOP NOP NOP ACTIVE

tAS tAH

tAS tAH

tAS tAH

ROW

ROW

BANK

COLUMN m(2)

tCHtCLtCK

tCMS tCMH

tCKS tCKH

BANK

tRCD

tRAS

tRC

CAS Latency

tAC tAC tAC tAC

tOH

tHZ

tOH

DOUT m

tOH

DOUT m+1

tOH

DOUT m+2 DOUT m+3

T0 T1 T2 T3 T4 T5 T6 T7 T8

tRP

ENABLE AUTO PRECHARGE

ROW

ROW

BANK

tLZ



01/30/08

IS42S16400

SINGLE READ WITHOUT AUTO PRECHARGE

DON'T CARE

UNDEFINED

CLK

CKE

COMMAND

DQM/DQML, DQMH

A0-A9, A11

A10

BA0, BA1

DQ

tCMS tCMH

ACTIVE NOP READ NOP NOP PRECHARGE NOP ACTIVE NOP

tAS tAH

tAS tAH

tAS tAH

ROW

ROW

BANK

COLUMN m(2)

tCHtCLtCK

tCMS tCMH

tCKS tCKH

BANK

tRCD

tRAS

tRC

CAS Latency

tAC

tHZ

tOH

DOUT m

T0 T1 T2 T3 T4 T5 T6 T7 T8

tRP


ROW

ROW

BANK

tLZ

ALL BANKS

SINGLE BANK

BANK



IS42S16400

SINGLE READ WITH AUTO PRECHARGE

DON'T CARE

UNDEFINED

CLK

CKE

COMMAND

DQM/DQML, DQMH

A0-A9, A11

A10

BA0, BA1

DQ

tCMS tCMH

ACTIVE NOP NOP NOP READ NOP NOP ACTIVE NOP

tAS tAH

tAS tAH

tAS tAH

ROW

ROW

BANK

COLUMN m(2)

tCHtCLtCK

tCMS tCMH

tCKS tCKH

BANK

tRCD

tRAS

tRC

CAS Latency

tAC

tHZ

tOH

DOUT m

T0 T1 T2 T3 T4 T5 T6 T7 T8

tRP


ROW

ROW

BANK



01/30/08

IS42S16400

ALTERNATING BANK READ ACCESSES

BANK 0 BANK 3 BANK 3 BANK 0

DON'T CARE

CLK

CKE

COMMAND

DQM/DQML, DQMH

A0-A9, A11

A10

BA0, BA1

DQ

tCMS tCMH

tAS tAH

tAS tAH

tAS tAH

tRCD - BANK 0 CAS Latency - BANK 0 tRCD - BANK 0

tRAS - BANK 0

tRC - BANK 0

tCHtCLtCK

tCMS tCMH

tCKS tCKH

ACTIVE NOP READ NOP ACTIVE NOP READ NOP ACTIVE

ROW

ROW

BANK 0

ROW ROW

tRRD tRCD - BANK 3

tRP - BANK 0

COLUMN m(2) ROW COLUMN b(2) ROW

ENABLE AUTO PRECHARGE ENABLE AUTO PRECHARGE

T0 T1 T2 T3 T4 T5 T6 T7 T8

tAC

tOH tOH tOH tOH tOH

DOUT m DOUT m+1 DOUT m+2 DOUT m+3 DOUT b

tAC tAC tAC tAC tAC

tLZ

CAS Latency - BANK 3



IS42S16400

READ - FULL-PAGE BURST

DON'T CARE

UNDEFINED

CLK

CKE

COMMAND

DQM/DQML, DQMH

A0-A9, A11

A10

BA0, BA1

DQ

tCMS tCMH

ACTIVE NOP READ NOP NOP NOP NOP NOP BURST TERM NOP NOP

tAS tAH

tAS tAH

tAS tAH

ROW

ROW

BANK

COLUMN m(2)

tCHtCLtCK

tCMS tCMH

tCKS tCKH

BANK

tRCD CAS Latency

tAC tACtAC tACtAC tHZ

tLZ

tAC

tOH tOH tOH tOH tOH tOH

DOUT m DOUT m+1 DOUT m+2 DOUT m-1 DOUT m DOUT m+1

each row (x4) has1,024 locations

Full pagecompletion

Full-page burst not self-terminating.Use BURST TERMINATE command.

T0 T1 T2 T3 T4 T5 T6 Tn+1 Tn+2 Tn+3 Tn+4

Notes:1. CAS latency = 2, burst length = full page2. A8, A9, and A11="Don'tCare"


01/30/08

IS42S16400

READ - DQM OPERATION

DON'T CARE

UNDEFINED

CLK

CKE

COMMAND

DQM/DQML, DQMH

A0-A9, A11

A10

BA0, BA1

DQ

tCMS tCMH

ACTIVE NOP READ NOP NOP NOP NOP NOP NOP

tAS tAH

tAS tAH

tAS tAH



ROW

ROW

BANK

tRCD CAS Latency

DOUT m DOUT m+2 DOUT m+3

COLUMN m(2)

BANK

tCHtCLtCK

tCMS tCMH

tCKS tCKH

tOHtOHtOH tACtAC

tACtHZ tHZtLZ tLZ

T0 T1 T2 T3 T4 T5 T6 T7 T8



IS42S16400

WRITE - WITHOUT AUTO PRECHARGE

DON'T CARE

CLK

CKE

COMMAND

DQM/DQML, DQMH

A0-A9, A11

A10

BA0, BA1

DQ

tCMS tCMH

tAS tAH

tAS tAH

tAS tAH

tRCD

tRAS

tRC

tCHtCLtCK

tCMS tCMH

tCKS tCKH

ACTIVE NOP WRITE NOP NOP NOP PRECHARGE NOP ACTIVE

tWR(3) tRP

COLUMN m(2) ROW

DISABLE AUTO PRECHARGEROW

ROW

ROW

BANK

tDS tDH tDS tDH tDS tDHtDS tDH

DIN m DIN m+1 DIN m+2 DIN m+3

BANK BANK BANK

ALL BANKS

SINGLE BANK

T0 T1 T2 T3 T4 T5 T6 T7 T8

Notes:1. burst length = 42. A8, A9, and A11="Don'tCare"3. tras must not be violated


01/30/08

IS42S16400

WRITE - WITH AUTO PRECHARGE

DON'T CARE

CLK

CKE

COMMAND

DQM/DQML, DQMH

A0-A9, A11

A10

BA0, BA1

DQ

tCMS tCMH

tAS tAH

tAS tAH

tAS tAH

tRCD

tRAS

tRC

tCHtCLtCK

tCMS tCMH

tCKS tCKH

ACTIVE NOP WRITE NOP NOP NOP NOP NOP NOP ACTIVE

tWR tRP

COLUMN m(2) ROW

BANK BANK

ENABLE AUTO PRECHARGEROW

ROW

ROW

BANK

tDS tDH tDS tDH tDS tDHtDS tDH

DIN m DIN m+1 DIN m+2 DIN m+3

T0 T1 T2 T3 T4 T5 T6 T7 T8 T9

Notes:1. burst length = 42. A8, A9, and A11="Don'tCare"


IS42S16400

SINGLE WRITE - WITHOUT AUTO PRECHARGE

DON'T CARE

CLK

CKE

COMMAND

DQM/DQML, DQMH

A0-A9, A11

A10

BA0, BA1

DQ

tCMS tCMH

tAS tAH

tAS tAH

tAS tAH

tDS tDH

tRCD

tRAS

tRC

tCHtCLtCK

tCMS tCMH

tCKS tCKH

ACTIVE NOP WRITE NOP(4) NOP(4) PRECHARGE NOP ACTIVE NOP

tWR(3) tRP


ROW

ROW

ROW

BANK

DIN m

COLUMN m(2) ROW

BANK BANK BANK

ALL BANKS

SINGLE BANK

T0 T1 T2 T3 T4 T5 T6 T7 T8

Notes:1. burst length = 12. A8, A9, and A11="Don'tCare"3. tras must not be violated


01/30/08

IS42S16400

SINGLE WRITE - WITH AUTO PRECHARGE

DON'T CARE

CLK

CKE

COMMAND

DQM/DQML, DQMH

A0-A9, A11

A10

BA0, BA1

DQ

tCMS tCMH

tAS tAH

tAS tAH

tAS tAH

tDS tDH

tRCD

tRAS

tRC

tCHtCLtCK

tCMS tCMH

tCKS tCKH

ACTIVE NOP(3) NOP(3) NOP(3) WRITE NOP NOP NOP ACTIVE NOP

tWR tRP

COLUMN m(2) ROW

BANK BANK


ROW

ROW

ROW

BANK

DIN m

T0 T1 T2 T3 T4 T5 T6 T7 T8 T9



IS42S16400

ALTERNATING BANK WRITE ACCESS

BANK 0 BANK 1 BANK 1 BANK 0

DON'T CARE

CLK

CKE

COMMAND

DQM/DQML, DQMH

A0-A9, A11

A10

BA0, BA1

DQ

tCMS tCMH

tAS tAH

tAS tAH

tAS tAH

tDS tDH tDS tDH tDS tDH

tRCD - BANK 0 tRCD - BANK 0tWR - BANK 1

tRAS - BANK 0tRC - BANK 0

tCHtCLtCK

tDS tDH tDS tDH tDS tDH tDS tDH tDS tDH

tCMS tCMH

tCKS tCKH

ACTIVE NOP WRITE NOP ACTIVE NOP WRITE NOP NOP ACTIVE

DIN m DIN m+1 DIN m+2 DIN m+3 DIN b DIN b+1 DIN b+2 DIN b+3

ROW

ROW

BANK 0

ROW ROW

tRRD tRCD - BANK 1

tWR - BANK 0 tRP - BANK 0

COLUMN m(2) ROW COLUMN b(2) ROW

ENABLE AUTO PRECHARGE ENABLE AUTO PRECHARGE

T0 T1 T2 T3 T4 T5 T6 T7 T8 T9



01/30/08

IS42S16400

DON'T CARE

CLK

CKE

COMMAND

DQM/DQML, DQMH

A0-A9, A11

A10

BA0, BA1

DQ

tCMS tCMH

ACTIVE NOP WRITE NOP NOP NOP NOP BURST TERM NOP

tAS tAH

tAS tAH

tAS tAH


ROW

ROW

BANK

tRCD

DIN m DIN m+1 DIN m+2 DIN m+3 DIN m-1

COLUMN m(2)

tCHtCLtCK


tCMS tCMH

tCKS tCKH

BANK

Full page completed

T0 T1 T2 T3 T4 T5 Tn+1 Tn+2

WRITE - FULL PAGE BURST

Notes:1. burst length = full page2. A8, A9, and A11="Don'tCare"


IS42S16400

DON'T CARE

CLK

CKE

COMMAND

DQM/DQML, DQMH

A0-A9, A11

A10

BA0, BA1

DQ

tCMS tCMH

ACTIVE NOP WRITE NOP NOP NOP NOP NOP

tAS tAH

tAS tAH

tAS tAH




ROW

ROW

BANK

tRCD

DIN m DIN m+2 DIN m+3

COLUMN m(2)

BANK

tCHtCLtCK

tCMS tCMH

tCKS tCKH

T0 T1 T2 T3 T4 T5 T6 T7

WRITE - DQM OPERATION



01/30/08

IS42S16400

ORDERING INFORMATION

Commercial Range: 0°C to 70°C Frequency Speed (ns) Order Part No. Package

166MHz 6 IS42S16400-6TL 400-milTSOPII,Lead-free

143MHz 7 IS42S16400-7TL 400-milTSOPII,Lead-free

Industrial Range: -40°C to 85°C Frequency Speed (ns) Order Part No. Package

166MHz 6 IS42S16400-6TLI 400-milTSOPII,Lead-free

143MHz 7 IS42S16400-7TLI 400-milTSOPII,Lead-free

PACKAGING INFORMATION

Integrated Silicon Solution, Inc. 1Rev. D03/13/07

Plastic TSOP 54–Pin, 86-PinPackage Code: T (Type II)

Plastic TSOP (T - Type II)Millimeters Inches

Symbol Min Max Min MaxRef. Std.

No. Leads (N) 54

A — 1.20 — 0.047A1 0.05 0.15 0.002 0.006A2 — — — —b 0.30 0.45 0.012 0.018C 0.12 0.21 0.005 0.0083D 22.02 22.42 0.867 0.8827E1 10.03 10.29 0.395 0.405E 11.56 11.96 0.455 0.471e 0.80 BSC 0.031 BSCL 0.40 0.60 0.016 0.024

L1 — — — — ZD 0.71 REF

α 0° 8° 0° 8°

D

SEATING PLANE

be C

1 N/2

N/2+1N

E1

A1

A

E

L α

ZD

Notes:1. Controlling dimension: millimieters,

unless otherwise specified.2. BSC = Basic lead spacing between

centers.3. Dimensions D and E1 do not include

mold flash protrusions and should bemeasured from the bottom of thepackage.

4. Formed leads shall be planar withrespect to one another within 0.004inches at the seating plane.

Plastic TSOP (T - Type II)Millimeters Inches

Symbol Min Max Min MaxRef. Std.

No. Leads (N) 86

A — 1.20 — 0.047A1 0.05 0.15 0.002 0.006A2 0.95 1.05 0.037 0.041b 0.17 0.27 0.007 0.011C 0.12 0.21 0.005 0.008D 22.02 22.42 0.867 0.8827E1 10.03 10.29 0.395 0.405E 11.56 11.96 0.455 0.471e 0.50 BSC 0.020 BSCL 0.40 0.60 0.016 0.024

L1 0.80 REF 0.031 REF ZD 0.61 REF 0.024 BSC

α 0° 8° 0° 8°

is42s16400

Documents

meg bits x

clock cycle

clock input

column addresses

burst access

precharge time

rising edge

internal banks