November 1994
54F/74F191
Up/Down Binary Counter with Preset and Ripple Clock
General Description
Features
The ’F191 is a reversible modulo-16 binary counter featur-
ing synchronous counting and asynchronous presetting.
The preset feature allows the ’F191 to be used in program-
mable dividers. The Count Enable input, the Terminal Count
output and Ripple Clock output make possible a variety of
methods of implementing multistage counters. In the count-
ing modes, state changes are initiated by the rising edge of
the clock.
Y
High-SpeedÐ125 MHz typical count frequency
Y
Synchronous counting
Y
Asynchronous parallel load
Y
Cascadable
Package
Commercial
74F191PC
Military
Package Description
Number
N16E
J16A
16-Lead (0.300 Wide) Molded Dual-In-Line
×
54F191DM (Note 2)
16-Lead Ceramic Dual-In-Line
74F191SC (Note 1)
74F191SJ (Note 1)
M16A
M16D
W16A
E20A
16-Lead (0.150 Wide) Molded Small Outline, JEDEC
×
16-Lead (0.300 Wide) Molded Small Outline, EIAJ
×
54F191FM (Note 2)
54F191LM (Note 2)
16-Lead Cerpack
20-Lead Ceramic Leadless Chip Carrier, Type C
e
Note 1: Devices also available in 13 reel. Use suffix
SCX and SJX.
×
Note 2: Military grade device with environmental and burn-in processing. Use suffix
e
DMQB, FMQB and LMQB.
Logic Symbols
Connection Diagrams
Pin Assignment for
DIP, SOIC and Flatpak
Pin Assignment
for LCC
TL/F/9495–1
IEEE/IEC
TL/F/9495–2
TL/F/9495–3
TL/F/9495–4
TRI-STATEÉ is a registered trademark of National Semiconductor Corporation.
C
1995 National Semiconductor Corporation
TL/F/9495
RRD-B30M75/Printed in U. S. A.