MC74VHCT257A
http://onsemi.com
4
DC CHARACTERISTICS (Voltages Referenced to GND)
V
CC
T
A
= 25°C T
A
≤ 85°C −55°C ≤ T
A
≤ 125°C
Symbol Parameter Condition (V) Min Typ Max Min Max Min Max Unit
V
IH
Minimum High−Level
Input Voltage
4.5 to 5.5 2 2 2 V
V
IL
Maximum Low−Level
Input Voltage
4.5 to 5.5 0.8 0.8 0.8 V
V
OH
Maximum High−Level
Output Voltage
V
IN
= V
IH
or V
IL
I
OH
= −50 mA
4.5 3.94 3.8 3.66
V
V
IN
= V
IH
or V
IL
I
OH
= −8 mA 4.5 3.94 3.8 3.66
V
OL
Maximum Low−Level
Output Voltage
V
IN
= V
IH
or V
IL
I
OL
= 50 mA
4.5 0 0.1 0.1 0.1
V
V
IN
= V
IH
or V
IL
I
OH
= 8 mA 4.5 0.36 0.44 0.52
I
IN
Input Leakage Current V
IN
= 5.5 V or GND 0 to 5.5 ±0.1 ±1.0 ±1.0
mA
I
OZ
Maximum 3−State
Leakage Current
V
IN
= V
IH
or V
IL
V
OUT
= V
CC
or GND
5.5 ±0.2
5
±2.5 ±2.5
mA
I
CCT
Maximum Quiescent
Supply Current
V
IN
= V
CC
or GND 5.5 1.35 1.5 1.65 mA
I
CC
Additional Quiescent
Supply Current (per pin)
V
IN
= V
CC
or GND 5.5 4.0 40 40
mA
I
OPD
Output Leakage Current V
OUT
= 5.5 V 0 0.5 5 5
mA
AC ELECTRICAL CHARACTERISTICS (Input t
r
= t
f
= 3.0ns)
Symbo
Parameter Test Conditions
T
A
= 25°C T
A
= ≤ 85°C −55°C ≤ T
A
≤ 125°C
Uni
Min Typ Max Min Max Min Max
t
PLH
,
t
PHL
Maximum Propagation De-
lay, A or B to Y
V
CC
= 3.3 ± 0.3 V C
L
= 15 pF
C
L
= 50 pF
5.8
8.3
9.3
12.8
1.0
1.0
11.0
14.5
1.0
1.0
11.0
14.5
ns
V
CC
= 5.0 ± 0.5 V C
L
= 15 pF
C
L
= 50 pF
3.6
5.1
5.9
7.9
1.0
1.0
7.0
9.0
1.0
1.0
7.0
9.0
t
PLH
,
t
PHL
Maximum Propagation De-
lay, S to Y
V
CC
= 3.3 ± 0.3 V C
L
= 15 pF
C
L
= 50 pF
7.0
9.5
11.0
14.5
1.0
1.0
13.0
16.5
1.0
1.0
13.0
16.5
ns
V
CC
= 5.0 ± 0.5 V C
L
= 15 pF
C
L
= 50 pF
4.0
5.5
6.8
8.8
1.0
1.0
8.0
10.0
1.0
1.0
8.0
10.0
t
PZL
,
t
PZH
Maximum Output Enable,
Time, OE to Y
V
CC
= 3.3 ± 0.3 V C
L
= 15 pF
R
L
= 1 kW C
L
= 50 pF
6.7
9.2
10.5
14.0
1.0
1.0
12.5
16.0
1.0
1.0
12.5
16.0
ns
V
CC
= 5.0 ± 0.5 V C
L
= 15 pF
R
L
= 1 kW C
L
= 50 pF
3.6
5.1
6.8
11.0
1.0
12.0
8.0
10.0
1.0
1.0
8.0
12.0
t
PLZ
,
t
PHZ
Maximum Output Disable,
Time, OE
to Y
V
CC
= 3.3 ± 0.3 V C
L
= 50 pF
R
L
= 1 kW
10.5 14.0 1.0 15.0 1.0 15.0
ns
V
CC
= 5.0 ± 0.5 V C
L
= 50 pF
R
L
= 1 kW
9.5 12.0 1.0 13.0 1.0 13.0
C
IN
Maximum Input Capacitance 4 10 10 10 pF
C
Power Dissipation Capacitance (Note 5)
Typical @ 25°C, V
CC
= 5.0 V
pF
20
5. C
PD
is defined as the value of the internal equivalent capacitance which is calculated from the operating current consumption without load.
Average operating current can be obtained by the equation: I
CC(OPR
)
= C
PD
V
CC
f
in
+ I
CC
. C
PD
is used to determine the no−load dynamic
power consumption; P
D
= C
PD
V
CC
2
f
in
+ I
CC
V
CC
.
NOISE CHARACTERISTICS (Input t
r
= t
f
= 3.0 ns, C
L
= 50 pF, V
CC
= 5.0 V)
Symbo
Characteristic
T
A
= 25°C
Uni
Typ Max
V
OLP
Quiet Output Maximum Dynamic V
OL
0.3 0.8 V
V
OLV
Quiet Output Minimum Dynamic V
OL
− 0.3 − 0.8 V
V
IHD
Minimum High Level Dynamic Input Voltage 2.0 V
V
ILD
Maximum Low Level Dynamic Input Voltage 0.8 V
