54AC169
•
54ACT169 4-Stage Synchronous Bidirectional Counter
July 1998
54AC169
•
54ACT169
4-Stage Synchronous Bidirectional Counter
General Description
The ’AC/’ACT169 is fully synchronous 4-stage up/down
counter. The ’AC/’ACT169 is a modulo-16 binary counter. It
features a preset capability for programmable operation,
carry lookahead for easy cascading and a U/D input to con-
trol the direction of counting. All state changes, whether in
counting or parallel loading, are initiated by the
LOW-to-HIGH transition of the Clock.
n
n
n
n
n
n
Synchronous counting and loading
Built-In lookahead carry capability
Presettable for programmable operation
Outputs source/sink 24 mA
’ACT has TTL-compatible inputs
Standard Microcircuit Drawing (SMD)
5962-91603
Features
n
I
CC
reduced by 50%
Logic Symbols
Pin
Names
CEP
CET
CP
P
0
–P
3
PE
U/D
DS100276-1
Description
Count Enable Parallel Input
Count Enable Trickle Input
Clock Pulse Input
Parallel Data Inputs
Parallel Enable Input
Up-Down Count Control Input
Flip-Flop Outputs
Terminal Count Output
Q
0
–Q
3
TC
IEEE/IEC
DS100276-2
FACT
™
is a trademark of Fairchild Semiconductor Corporation.
© 1998 National Semiconductor Corporation
DS100276
www.national.com
NSC [ NATIONAL SEMICONDUCTOR ]
