HD74HC190 Datasheet, PDF (3/13 Pages) Hitachi Semiconductor – Synchronous Up/Down Decade,4-bit Binary Counter(Single Clock Line)

HD74HC190, HD74HC191
Timing Chart
HD74HC190
Illustrated below is the following sequence:
1. Load (preset) to BCD seven.
2. Count up to eight, nine (maximum), zero, one and two.
3. Inhibit
4. Count down to one, zero (minimum), nine, eight and seven.
Load
A
B
C
D
Clock
Down/Up
Enable G
QA
QB
QC
QD
Max/Min
Ripple
Clock
7 8 9 0 12
221 0 9 8 7
Load
Count Up
Inhibit
Count Down
Rev.3.00, Jan 31, 2006 page 3 of 12