74FST3257
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4
DC ELECTRICAL CHARACTERISTICS
V
CC
T
A
= −40_C to +85_C
Symbol Parameter Conditions (V) Min Typ* Max Units
V
IK
Clamp Diode Voltage I
IN
= −18 mA 4.5 −1.2 V
V
IH
High−Level Input Voltage 4.0 to 5.5 2.0 V
V
IL
Low−Level Input Voltage 4.0 to 5.5 0.8 V
I
I
Input Leakage Current 0 ≤ V
IN
≤ 5.5 V 5.5 ±1.0
mA
I
OZ
Off−State Leakage Current 0 ≤ A, B ≤ V
CC
5.5 ±1.0
mA
R
ON
Switch On Resistance (Note 6) V
IN
= 0 V, I
IN
= 64 mA 4.5 4 7
W
V
IN
= 0 V, I
IN
= 30 mA 4.5 4 7
V
IN
= 2.4 V, I
IN
= 15 mA 4.5 8 15
V
IN
= 2.4 V, I
IN
= 15 mA 4.0 11 20
I
CC
Quiescent Supply Current V
IN
= V
CC
or GND, I
OUT
= 0 5.5 3
mA
DI
CC
Increase In I
CC
per Input One input at 3.4 V,
Other inputs at V
CC
or GND
5.5 2.5 mA
*Typical values are at V
CC
= 5.0 V and T
A
= 25_C.
6. Measured by the voltage drop between A and B pins at the indicated current through the switch. On resistance is determined by the lower
of the voltages on the two (A or B) pins.
AC ELECTRICAL CHARACTERISTICS
T
A
= −40_C to +85_C
C
L
= 50 pF, RU = RD = 500 W
V
CC
= 4.5−5.5 V V
CC
= 4.0 V
Symbol Parameter Conditions Min Max Min Max Units
t
PHL
,
t
PLH
Prop Delay Bus to Bus (Note 7)
V
I
= OPEN
0.25 0.25
ns
Prop Delay, Select to Bus A 1.0 4.7 5.2
t
PZH
,
t
PZL
Output Enable Time, Select to Bus B V
I
= 7 V for t
PZL
1.0 5.2 5.7
ns
Output Enable Time, I
OE
to Bus A, B V
I
= OPEN for t
PZH
1.0 5.1 5.6
t
PHZ
,
t
PLZ
Output Disable Time, Select to Bus B V
I
= 7 V for t
PLZ
1.0 5.2 5.5
ns
Output Disable Time, I
OE
to Bus A, B V
I
= OPEN for t
PHZ
1.0 5.5 5.5
7. This parameter is guaranteed by design but is not tested. The bus switch contributes no propagation delay other than the RC delay of the
typical On resistance of the switch and the 50 pF load capacitance, when driven by an ideal voltage source (zero output impedance).
CAPACITANCE (Note 8)
Symbol
Parameter Conditions Typ Max Units
C
IN
Control Pin Input Capacitance V
CC
= 5.0 V 3 pF
C
I/O
A Port Input/Output Capacitance V
CC
, OE = 5.0 V 7 pF
C
I/O
B Port Input/Output Capacitance V
CC
, OE = 5.0 V 5 pF
8. T
A
= )25_C, f = 1 MHz, Capacitance is characterized but not tested.
