HD74LS191 Datasheet, PDF (2/11 Pages) Hitachi Semiconductor – Synchronous Up/Down 4-bit Binary Counters(single clock line)

HD74LS191
Pin Arrangement
Data B
Input
1
Outputs
QB 2
QA 3
Enable G 4
Inputs
Down/Up 5
Outputs
QC 6
QD 7
GND 8
B
QB
A
QA
CK
G
Ripple
Clock
Dn/Up
Max/
Min
QC
Load
QD
C
D
(Top view)
16 V_CC
15 _{Data A}
14 _Clock
13
Ripple
Clock
12 _Max/Min
11 _Load
10 _{Data C}
9 _{Data D}
Inputs
Outputs
Inputs
Rev.2.00, Feb.18.2005, page 2 of 10