HD74HC668 Datasheet, PDF (4/11 Pages) Hitachi Semiconductor – Synchronous UP/Down Decade,4-bit binary Counter

HD74HC668, HD74HC669
Timing Chart
HD74HC668
Load
A
B
Data
inputs
C
D
Clock
U/D
Enable P and T
QA
QB
QC
QD
Ripple
carry
output
7
8
9
0
12
2
21
0
9
8
7
Load
Count up
Inhibit
Count down
Rev.2.00 Mar 30, 2006 page 4 of 10