HD74LS74A
Electrical Characteristics
(Ta = –20 to +75 °C)
Item
Input voltage
Symbol
V
IH
V
IL
V
OH
Output voltage
V
OL
D
Clear
Preset
Clock
Input
current
D
Clear
Preset
Clock
D
Clear
Preset
Clock
Short-circuit output
current
Supply current
min.
2.0
—
2.7
—
—
—
—
—
—
—
—
—
—
—
—
—
—
–20
—
typ.*
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
4
max.
—
0.8
—
0.5
0.4
20
40
40
20
–0.4
–0.8
–0.8
–0.4
0.1
0.2
0.2
0.1
–100
8
Unit
V
V
V
V
V
CC
= 4.75 V, V
IH
= 2 V, V
IL
= 0.8 V,
I
OH
= –400
µA
I
OL
= 8 mA
I
OL
= 4 mA
V
CC
= 4.75 V, V
IL
= 0.8 V,
V
IH
= 2 V
Condition
I
IH
µA
V
CC
= 5.25 V, V
I
= 2.7 V
I
IL
mA
V
CC
= 5.25 V, V
I
= 0.4 V
I
I
mA
V
CC
= 5.25 V, V
I
= 7 V
I
OS
I
CC
**
mA
mA
V
CC
= 5.25 V
V
CC
= 5.25 V
Input clamp voltage
V
IR
—
—
–1.5
V
V
CC
= 4.75 V, I
IN
= –18 mA
Notes: * V
CC
= 5 V, Ta = 25
°
C
** With all output open, I
CC
is measured with the Q and
Q
outputs high in turn. At the time of measurement, the
clock input is grounded.
Switching Characteristics
(V
CC
= 5 V, Ta = 25°C)
Item
Maximum clock frequency
Propagation delay time
Symbol
f
max
t
PLH
t
PHL
Inputs
Clear, Clock
or Preset
Outputs
Q,
Q
min.
25
—
—
typ.
33
13
25
max.
25
40
Unit
MHz
ns
ns
Condition
C
L
= 15 pF,
R
L
= 2 kΩ
Timing Definition
t
w
3V
1.3 V
Clock
t
su
t
h
t
su
t
h
1.3 V
1.3 V
0V
3V
1.3 V
Data
"H" Data
"L" Data
1.3 V
1.3 V
0V
Rev.3.00, Jul.22.2005, page 3 of 7