5-302
FAST AND LS TTL DATA
BCD DECADE/MODULO
16 BINARY SYNCHRONOUS
BI-DIRECTIONAL COUNTERS
The SN54/74LS168 and SN54/74LS169 are fully synchronous 4-stage
up/down counters featuring a preset capability for programmable operation,
carry lookahead for easy cascading and a U/D input to control the direction
of counting. The SN54/74LS168 counts in a BCD decade (8, 4, 2, 1)
sequence, while the SN54/74LS169 operates in a Modulo 16 binary
sequence. All state changes, whether in counting or parallel loading, are
initiated by the LOW-to-HIGH transition of the clock.
• Low Power Dissipation 100 mW Typical
• High-Speed Count Frequency 30 MHz Typical
• Fully Synchronous Operation
• Full Carry Lookahead for Easy Cascading
• Single Up/Down Control Input
• Positive Edge-Trigger Operation
• Input Clamp Diodes Limit High-Speed Termination Effects
NOTE:
The Flatpak version
has the same pinouts
(Connection Diagram) as
the Dual In-Line Package.
C0049C0052 C0049C0051 C0049C0050 C0049C0049 C0049C0048 C0057
C0049 C0050 C0051 C0052 C0053 C0054 C0055
C0049C0054 C0049C0053
C0056
C0086
C0067C0067
C0085C0047C0068
C0084C0067 C0081
C0048
C0081
C0049
C0081
C0050
C0067C0069C0084C0081
C0051
C0080C0069
C0067C0080 C0080
C0048
C0080
C0049
C0080
C0050
C0080
C0051
C0067C0069C0080 C0071C0078C0068
CONNECTION DIAGRAM DIP (TOP VIEW)
PIN NAMES LOADING (Note a)
HIGH LOW
CEP
CET
CP
PE
U/D
P
0
–P
3
Q
0
–Q
3
TC
Count Enable Parallel (Active LOW) Input
Count Enable Trickle (Active LOW) Input
Clock Pulse (Active positive going edge) Input
Parallel Enable (Active LOW) Input
Up-Down Count Control Input
Parallel Data Inputs
Flip-Flop Outputs
Terminal Count (Active LOW) Output
0.5 U.L.
1.0 U.L.
0.5 U.L.
0.5 U.L.
0.5 U.L.
0.5 U.L.
10 U.L.
10 U.L.
0.25 U.L.
0.5 U.L.
0.25 U.L.
0.25 U.L.
0.25 U.L.
0.25 U.L.
5 (2.5) U.L.
5 (2.5) U.L.
NOTES:
a. 1 TTL Unit Load (U.L.) = 40 µA HIGH/1.6 mA LOW.
b. The Output LOW drive factor is 2.5 U.L. for Military (54) and 5 U.L. for Commercial (74)
b. Temperature Ranges.
SN54/74LS168
SN54/74LS169
BCD DECADE/MODULO
16 BINARY SYNCHRONOUS
BI-DIRECTIONAL COUNTERS
LOW POWER SCHOTTKY
J SUFFIX
CERAMIC
CASE 620-09
N SUFFIX
PLASTIC
CASE 648-08
16
1
16
1
ORDERING INFORMATION
SN54LSXXXJ Ceramic
SN74LSXXXN Plastic
SN74LSXXXD SOIC
16
1
D SUFFIX
SOIC
CASE 751B-03
LOGIC SYMBOL
C0057 C0051 C0052 C0053 C0054
C0055
C0049C0048
C0050
C0049C0053
C0049C0052 C0049C0051 C0049C0050 C0049C0049
C0080C0069 C0080
C0048
C0080
C0049
C0080
C0050
C0080
C0051
C0067C0069C0080
C0067C0069C0084
C0067C0080
C0081
C0048
C0081
C0049
C0081
C0050
C0081
C0051
C0084C0067
C0086
C0067C0067
C0061 C0080C0073C0078 C0049C0054
C0071C0078C0068 C0061 C0080C0073C0078 C0056
C0049 C0085C0047C0068