TL/F/9495
54F/74F191
Up/Down
Binary
Counter
with
Preset
and
Ripple
Clock
November 1994
54F/74F191
Up/Down Binary Counter with Preset and Ripple Clock
General Description
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.
Features
Y
High-Speed—125 MHz typical count frequency
Y
Synchronous counting
Y
Asynchronous parallel load
Y
Cascadable
Commercial Military
Package
Package Description
Number
74F191PC N16E 16-Lead (0.300 Wide) Molded Dual-In-Line
54F191DM (Note 2) J16A 16-Lead Ceramic Dual-In-Line
74F191SC (Note 1) M16A 16-Lead (0.150 Wide) Molded Small Outline, JEDEC
74F191SJ (Note 1) M16D 16-Lead (0.300 Wide) Molded Small Outline, EIAJ
54F191FM (Note 2) W16A 16-Lead Cerpack
54F191LM (Note 2) E20A 20-Lead Ceramic Leadless Chip Carrier, Type C
Note 1: Devices also available in 13 reel. Use suffix e SCX and SJX.
Note 2: Military grade device with environmental and burn-in processing. Use suffix e DMQB, FMQB and LMQB.
Logic Symbols
TL/F/9495–1
IEEE/IEC
TL/F/9495–4
Connection Diagrams
Pin Assignment for
DIP, SOIC and Flatpak
TL/F/9495–2
Pin Assignment
for LCC
TL/F/9495–3
TRI-STATE is a registered trademark of National Semiconductor Corporation.
C
1995 National Semiconductor Corporation RRD-B30M75/Printed in U. S. A.