English
Language : 

IDT70V18L Datasheet, PDF (8/17 Pages) Integrated Device Technology – HIGH-SPEED 3.3V 64K x 9 DUAL-PORT STATIC RAM
IDT70V18L
High-Speed 3.3V 64K x 9 Dual-Port Static RAM
Preliminary
Industrial and Commercial Temperature Ranges
Timing Waveform of Write Cycle No. 1, R/W Controlled Timing(1,5,8)
tWC
ADDRESS
tHZ (7)
OE
tAW
CE or SEM(9,10)
R/W
DATAOUT
DATAIN
tAS (6)
(4)
tWP (2)
tWZ (7)
tDW
tWR(3)
tOW
tDH
(4)
4854 drw 07
Timing Waveform of Write Cycle No. 2, CE Controlled Timing(1,5)
ADDRESS
CE or SEM(9,10)
R/W
DATAIN
tAS(6)
tWC
tAW
tEW (2)
tWR(3)
tDW
tDH
4854 drw 08
NOTES:
1. R/W or CE = VIH during all address transitions.
2. A write occurs during the overlap (tEW or tWP) of a CE = VIL and a R/W = VIL for memory array writing cycle.
3. tWR is measured from the earlier of CE or R/W (or SEM or R/W) going HIGH to the end of write cycle.
4. During this period, the I/O pins are in the output state and input signals must not be applied.
5. If the CE or SEM = VIL transition occurs simultaneously with or after the R/W = VIL transition, the outputs remain in the High-impedance state.
6. Timing depends on which enable signal is asserted last, CE or R/W.
7. This parameter is guaranteed by device characterization, but is not production tested. Transition is measured 0mV from steady state with the Output Test Load
(Figure 2).
8. If OE = VIL during R/W controlled write cycle, the write pulse width must be the larger of tWP or (tWZ + tDW) to allow the I/O drivers to turn off and data to be placed on the bus
for the required tDW. If OE = VIH during an R/W controlled write cycle, this requirement does not apply and the write pulse can be as short as the specified tWP.
9. To access RAM, CE = VIL and SEM = VIH. To access semaphore, CE = VIH and SEM = VIL. tEW must be met for either condition.
10. Refer to Truth Table I - Chip Enable .
8