Datasheet

DS8007
Multiprotocol Dual Smart Card Interface
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AC ELECTRICAL SPECIFICATIONS—TIMING PARAMETERS FOR MULTIPLEXED
PARALLEL BUS
(V
DD
= 3.3V, V
DDA
= 3.3V, T
A
= +25°C, unless otherwise noted.) (Figure 1)
PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS
XTAL1 Cycle Time t
CY(XTAL1)
50 ns
ALE Pulse Width t
W(ALE)
20 ns
Address Valid to ALE Low t
AVLL
10 ns
ALE Low to RD or WR Low t
(AL-RWL)
10 ns
Register URR 2 x t
CY(XTAL1)
RD Pulse Width t
W(RD)
Other registers 10
ns
RD Low to Data Read Valid t
(RL-DV)
50 ns
WR/RD High to ALE High t
(RWH-AH)
10 ns
WR Pulse Width t
W(WR)
10 ns
Data Write Valid to WR Low t
(DV-WL)
10 ns
ALE
CS
D7–D0
RD
WR
ADDRESS ADDRESS
DATA
(READ)
DATA
(WRITE)
t
W(ALE)
t
AVLL
t
(AL-RWL)
t
W(RD)
t
(RL-DV)
t
(RWH-AH)
t
(DV-WL)
t
(RWH-AH)
t
W(WR)
Figure 1. Multiplexed Parallel Bus Timing