12 Integrated Silicon Solution, Inc. — www.issi.com — 1-800-379-4774
Rev. C
06/23/2014
IS61WV20488ALL, IS61/64WV20488BLL
WRITE CYCLE SWITCHING CHARACTERISTICS
(1,2)
(OverOperatingRange)
-20 ns
Symbol Parameter Min. Max. Unit
twc WriteCycleTime 20 — ns
tsce CEtoWriteEnd 12 — ns
taw AddressSetupTime 12 — ns
toWriteEnd
tha AddressHoldfromWriteEnd 0 — ns
tsa AddressSetupTime 0 — ns
tPwe1 WE Pulse Width (OE = HIGH) 12 — ns
tPwe2 WE Pulse Width (OE=LOW) 17 — ns
tsd DataSetuptoWriteEnd 9 — ns
thd DataHoldfromWriteEnd 0 — ns
thzwe
(3)
WELOWtoHigh-ZOutput — 9 ns
tlzwe
(3)
WEHIGHtoLow-ZOutput 3 — ns
Notes:
1. Test conditions assume signal transition times of 1.5ns or less, timing reference levels of 1.25V, input
pulse levels of 0.4V to V
dd-0.3VandoutputloadingspeciedinFigure1.
2. TestedwiththeloadinFigure2.Transitionismeasured±500mVfromsteady-statevoltage.Not100%
tested.
3. TheinternalwritetimeisdenedbytheoverlapofCELOWandWELOW.Allsignalsmustbeinvalid
statestoinitiateaWrite,butanyonecangoinactivetoterminatetheWrite.TheDataInputSetupand
Hold timing are referenced to the rising or falling edge of the signal that terminates the write.