—ꢀ
—ꢀ
—ꢀ
—ꢀ
—ꢀ
—ꢀ
—ꢀ
—ꢀ
Active
High-Z
Hꢀ
—ꢀ
IS42S16400F
IC42S16400F
TRUTH TABLE – COMMANDS AND DQM OPERATION(1)
FUNCTION
CS
Hꢀ
Lꢀ
RAS CAS
WE DQM
ADDR
Xꢀ
DQs
COMMANDꢀINHIBITꢀ(NOP)ꢀ
Xꢀ
Hꢀ
Lꢀ
Xꢀ
Hꢀ
Hꢀ
Lꢀ
Xꢀ
Hꢀ
Hꢀ
Hꢀ
Lꢀ
Xꢀ
Xꢀ
X
X
NOꢀOPERATIONꢀ(NOP)ꢀ
Xꢀ
ACTIVEꢀ(Selectꢀbankꢀandꢀactivateꢀrow)(3)ꢀ
READꢀ(Selectꢀbank/column,ꢀstartꢀREADꢀburst)(4)
WRITEꢀ(Selectꢀbank/column,ꢀstartꢀWRITEꢀburst)(4)ꢀ Lꢀ
BURSTꢀTERMINATEꢀ Lꢀ
PRECHARGEꢀ(Deactivateꢀrowꢀinꢀbankꢀorꢀbanks)(5)ꢀ Lꢀ
Lꢀ
Xꢀ
Bank/Rowꢀ
Bank/Colꢀ
Bank/Colꢀ
Xꢀ
X
ꢀ
Lꢀ
Hꢀ
Hꢀ
Hꢀ
Lꢀ
L/H(8)
L/H(8)
Xꢀ
X
Lꢀ
Valid
Active
X
Hꢀ
Hꢀ
Lꢀ
Lꢀ
Lꢀ
Xꢀ
Codeꢀ
Xꢀ
AUTOꢀREFRESHꢀorꢀSELFꢀREFRESH(6,7)
ꢀ
Lꢀ
Lꢀ
Hꢀ
Xꢀ
X
(Enterꢀselfꢀrefreshꢀmode)
LOADꢀMODEꢀREGISTER(2)ꢀ
WriteꢀEnable/OutputꢀEnable(8)ꢀ
WriteꢀInhibit/OutputꢀHigh-Z(8)ꢀ
Lꢀ
Lꢀ
Lꢀ
Lꢀ
Xꢀ
Lꢀ
Op-Codeꢀ
—ꢀ
X
NOTES:
1.ꢀ CKEꢀisꢀHIGHꢀforꢀallꢀcommandsꢀexceptꢀSELFꢀREFRESH.
2. A0-A11 define the op-code written to the mode register.
3.ꢀ A0-A11ꢀprovideꢀrowꢀaddress,ꢀandꢀBA0,ꢀBA1ꢀdetermineꢀwhichꢀbankꢀisꢀmadeꢀactive.
4.ꢀ A0-A7ꢀ(x16)ꢀprovideꢀcolumnꢀaddress;ꢀA10ꢀHIGHꢀenablesꢀtheꢀautoꢀprechargeꢀfeatureꢀ(nonpersistent),ꢀwhileꢀA10ꢀLOWꢀdisablesꢀ
autoꢀprecharge;ꢀBA0,ꢀBA1ꢀdetermineꢀwhichꢀbankꢀisꢀbeingꢀreadꢀfromꢀorꢀwrittenꢀto.
5.ꢀ A10ꢀLOW:ꢀBA0,ꢀBA1ꢀdetermineꢀtheꢀbankꢀbeingꢀprecharged.ꢀA10ꢀHIGH:ꢀAllꢀbanksꢀprechargedꢀandꢀBA0,ꢀBA1ꢀareꢀ“Don’tꢀCare.”
6.ꢀ AUTOꢀREFRESHꢀifꢀCKEꢀisꢀHIGH,ꢀSELFꢀREFRESHꢀifꢀCKEꢀisꢀLOW.
7.ꢀ Internalꢀrefreshꢀcounterꢀcontrolsꢀrowꢀaddressing;ꢀallꢀinputsꢀandꢀI/Osꢀareꢀ“Don’tꢀCare”ꢀexceptꢀforꢀCKE.
8.ꢀ ActivatesꢀorꢀdeactivatesꢀtheꢀDQsꢀduringꢀWRITEsꢀ(zero-clockꢀdelay)ꢀandꢀREADsꢀ(two-clockꢀdelay).
6
Integrated Silicon Solution, Inc. — www.issi.com
Rev. A
03/19/08
ISSI [ INTEGRATED SILICON SOLUTION, INC ]
