HD74LVC74
Function Table
Inputs
Outputs
PR
CLR
CK
D
Q
Q
L
H
X
X
H
L
H
L
X
X
L
H
L
L
X
X
H *1
H *1
H
H
↑
H
H
L
H
H
↑
L
L
H
H
H
H
H:
L:
X:
↓:
↑:
Q0:
Note:
H
L
X
Q0
Q0
H
H
X
Q0
Q0
H
↓
X
Q0
Q0
High level
Low level
Immaterial
High to Low transition
Low to high transition
Level to Q before the indicated steady input conditions were established.
1. Q and Q will remain high as long as preset and clear are low, but Q and Q are unpredictable, if
preset and clear go high simultaneously.
Pin Arrangement
1CLR 1
1D 2
1CK 3
1PR 4
1Q 5
1Q 6
GND 7
CK D
PR CLR
QQ
D CK
CLR PR
QQ
(Top view)
14 VCC
13 2CLR
12 2D
11 2CK
10 2PR
9 2Q
8 2Q
2