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74AC251 • 74ACT251
DC Electrical Characteristics for ACT
Note 5: All outputs loaded; thresholds on input associated with output under test.
Note 6: Maximum test duration 2.0 ms, one output loaded at a time.
AC Electrical Characteristics for AC
Note 7: Voltage Range 3.3 is 3.3V ± 0.3V.
Voltage Range 5.0 is 5.0V ± 0.5V
Symbol Parameter
V
CC
(V)
T
A
= +25°C T
A
= −40°C to +85°C
Units Conditions
Typ Guaranteed Limits
V
IH
Minimum HIGH Level 4.5 1.5 2.0 2.0
V
V
OUT
= 0.1V
Input Voltage 5.5 1.5 2.0 2.0 or V
CC
− 0.1V
V
IL
Maximum LOW Level 4.5 1.5 0.8 0.8
V
V
OUT
= 0.1V
Input Voltage 5.5 1.5 0.8 0.8 or V
CC
− 0.1V
V
OH
Minimum HIGH Level 4.5 4.49 4.4 4.4
VI
OUT
= −50 µA
Output Voltage 5.5 5.49 5.4 5.4
V
IN
= V
IL
or V
IH
4.5 3.86 3.76 V I
OH
= −24 mA
5.5 4.86 4.76 I
OH
= −24 mA (Note 5)
V
OL
Maximum LOW Level 4.5 0.001 0.1 0.1
VI
OUT
= 50 µA
Output Voltage 5.5 0.001 0.1 0.1
V
IN
= V
IL
or V
IH
4.5 0.36 0.44 V I
OL
= 24 mA
5.5 0.36 0.44 I
OL
= 24 mA (Note 5)
I
IN
Maximum Input
5.5 ±0.1 ±1.0 µAV
I
= V
CC
, GND
Leakage Current
I
OZ
Maximum 3-STATE
5.5 ±0.5 ±5.0 µA
V
I
= V
IL
, V
IH
Current V
O
= V
CC
, GND
I
CCT
Maximum
5.5 0.6 1.5 mA V
I
= V
CC
− 2.1V
I
CC
/Input
I
OLD
Minimum Dynamic 5.5 75 mA V
OLD
= 1.65V Max
I
OHD
Output Current (Note 6) 5.5 −75 mA V
OHD
= 3.85V Min
I
CC
Maximum Quiescent
5.5 4.0 40.0 µA
V
IN
= V
CC
Supply Current or GND
V
CC
T
A
= +25°CT
A
= −40°C to +85°C
Symbol Parameter (V)
C
L
= 50 pF C
L
= 50 pF
Units
(Note 7) Min Typ Max Min Max
t
PLH
Propagation Delay 3.3 1.5 11.5 17.5 1.5 19.0
ns
S
n
to Z or Z 5.0 1.5 8.5 12.5 1.5 13.5
t
PHL
Propagation Delay 3.3 1.5 11.0 17.5 1.5 19.0
ns
S
n
to Z or Z 5.0 1.5 8.0 12.5 1.5 13.5
t
PLH
Propagation Delay 3.3 1.5 10.0 14.0 1.5 15.5
ns
I
n
to Z or Z 5.0 1.5 7.0 10.0 1.5 11.0
t
PHL
Propagation Delay 3.3 1.5 9.0 14.0 1.5 15.5
ns
I
n
to Z or Z 5.0 1.5 6.5 10.0 1.5 11.0
t
PZH
Output Enable Time 3.3 1.5 7.5 11.0 1.5 12.0
ns
OE to Z or Z 5.0 1.5 5.5 8.0 1.5 9.0
t
PZL
Output Enable Time 3.3 1.5 7.5 11.0 1.5 12.0
ns
OE to Z or Z 5.0 1.5 5.5 8.0 1.5 9.0
t
PHZ
Output Disable Time 3.3 1.5 8.5 11.5 1.5 13.0
ns
OE to Z or Z 5.0 1.5 7.0 9.5 1.5 10.0
t
PLZ
Output Disable Time 3.3 1.5 7.0 11.0 1.5 12.0
ns
OE to Z or Z 5.0 1.5 5.5 8.0 1.5 8.5
