Datasheet

2
Pinout
CD54HC123, CD54HCT123
(CERDIP)
CD74HC123
(PDIP, SOIC, SOP, TSSOP)
CD74HC423
(PDIP, SOIC, SOP)
CD74HCT123, CD74HCT423
(PDIP, SOIC)
TOP VIEW
Functional Diagram
14
15
16
9
13
12
11
10
1
2
3
4
5
7
6
8
1A
1B
1R
1Q
2Q
2C
X
GND
2R
X
C
X
V
CC
1C
X
1Q
2Q
2R
2B
2A
1R
X
C
X
2R
11
2A
9
10
5
12
2Q
2Q
2B
MONO 2
V
CC
67
2Cx 2RxCx
1R
3
1A
2
1
13
4
1Q
1Q
1B
MONO 1
V
CC
14 15
1Cx 1RxCx
1Cx 1Rx
2Cx 2Rx
TRUTH TABLE
INPUTS OUTPUTS
ABRQQ
CD74HC/HCT123
HXHLH
XLHLH
L ↑ H
↓ HH
XXLLH
LH↑
CD74HC/HCT423
HXHLH
XLHLH
L ↑ H
↓ HH
XXLLH
H = High Voltage Level, L = Low Voltage Level,
X = Don’t Care.
CD54/74HC123, CD54/74HCT123, CD74HC423, CD74HCT423