Datasheet

December 1990 4
Philips Semiconductors Product specification
Dual decade ripple counter 74HC/HCT390
Fig.4 Functional diagram.
BCD COUNT SEQUENCE
FOR 1/2 THE “390”
Notes
1. Output Q
0
connected to nCP
1
with counter input on nCP
0
.
H = HIGH voltage level
L = LOW voltage level
COUNT
OUTPUTS
Q
0
Q
1
Q
2
Q
3
0 LLLL
1 HLLL
2LHLL
3 HHLL
4 LLHL
5HLHL
6 LHHL
7 HHHL
8 LLLH
9 HLLH
BI-QUINARY COUNT SEQUENCE
FOR 1/2 THE “390”
Note
1. Output Q
3
connected to nCP
0
with counter input on nCP
1
.
COUNT
OUTPUTS
Q
0
Q
1
Q
2
Q
3
0 LLLL
1LHLL
2 LLHL
3 LHHL
4 LLLH
5 HLLL
6 HHLL
7HLHL
8 HHHL
9 HLLH
Fig.5 Logic diagram (one counter).