SL74LS161
FUNCTION TABLE
Inputs
Outputs
Q1 Q2
Reset
Load
Enable
P
Enable
T
Clock
X
Q0
Q3
Function
L
H
H
H
H
H
X
L
X
X
X
L
X
X
L
L
L
L
L
Reset to “0”
Preset Data
No count
No count
Count
P0
P1
P2
P3
H
H
H
X
No change
No change
Count up
X
H
X
H
X
No change
No count
X=don’ t care
P0,P1,P2,P3 = logic level of Data inputs
Ripple Carry Out = Enable T · Q0 · Q1 · Q2 · Q3
MAXIMUM RATINGS*
Symbol
Parameter
Value
7.0
Unit
V
VCC
Supply Voltage
Input Voltage
Output Voltage
V
IN
7.0
V
VOUT
Tstg
5.5
V
Storage Temperature Range
-65 to +150
°C
*Maximum Ratings are those values beyond which damage to the device may occur.
Functional operation should be restricted to the Recommended Operating Conditions.
RECOMMENDED OPERATING CONDITIONS
Symbol
Parameter
Min
4.75
2.0
Max
Unit
V
VCC
Supply Voltage
5.25
V
IH
High Level Input Voltage
Low Level Input Voltage
High Level Output Current
Low Level Output Current
Clock frequency
V
V
IL
0.8
-0.4
8.0
25
V
IOH
IOL
mA
mA
fclock
0
MHz
ns
tw(clock)
tw(reset)
Width of clock pulse
Width of reset pulse
25
20
20
20
20
3
ns
Data inputs P0, P1, P2, P3
tsu
Setup time
Enable P or T
Load
ns
th
Hold time at any input
ns
TA
Ambient Temperature Range
0
+70
°C
System Logic
Semiconductor
SLS
SLS [ SYSTEM LOGIC SEMICONDUCTOR ]
