TECHNICAL DATA
1
Quad 2-Input Data Selector /M ultiple xe r
This monolitic data selector/multiplexer contains inverters and
drivers to supply full on-chip data selection to the four output gates. A
separate strobe input is provided. A 4-bit word is selected from one of
two sources and is routed to the four outputs. The LS157 has the same
functions and pin connections as the LS257 but the latter is provided
with 3-state outputs.
• Buffered Inputs and Outputs
• Common Strobe/Select input for all 4 circuits
IN74LS157
ORDERING INFORMATION
IN74LS157N Plastic
IN74LS157D SOIC
TA =0° to 70° C for all
packages
FUNCTION TABLE
Inputs Outputs
Output
Enable Select Y0-Y3
HXL
LLA0-A3
LHB0-B3
X=don’t care
A0-A3,B0-B3=the levels of the respective
Data-Word Inputs
LOGIC DIAGRAM
PIN 16 =VCC
PIN 8 = GND
PIN ASSIGNMENT
IN74LS157
2
MAXIMUM RATINGS*
Symbol Parameter Value Unit
VCC Supply Voltage 7.0 V
VIN Input Voltage 7.0 V
VOUT Output Voltage 5.5 V
Tstg 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 Max Unit
VCC Supply Voltage 4.75 5.25 V
VIH High Level Input Voltage 2.0 V
VIL Low Level Input Voltage 0.8 V
IOH High Level Output Current -0.4 mA
IOL Low Level O utput Current 8.0 mA
TAAmbient Temperature Range 0 +70 °C
DC ELECTRICAL CHARACTERISTICS over full operating conditions
Guaranteed Limit
Symbol Parameter Test Conditions Min Ma x Unit
VIK Input Clamp Voltage VCC = min, IIN = -18 mA -1.5 V
VOH High Level Output Vo ltage VCC = min, IOH = -0.4 mA 2.7 V
VOL Low Level Output Voltage VCC = min, IOL = 4 mA 0.4 V
VCC = min, IOL = 8 mA 0.5
IIH High Level Input Curr ent VCC = max for pins 1,15 40 µA
VIN = 2.7 V A or B input 20
VCC = max for pins 1,15 0.2 mA
VIN = 7.0 V A or B input 0.1
IIL Low Level Input Current VCC = max for pins 1,15 -0.8 mA
VIN = 0.4 V A or B input -0.4
IOOutput Short Circuit Current VCC = max, VO = 0 V
(Note 1) -20 -100 mA
ICC Supply Current VCC = max (Note 2) 16 mA
Note 1: Not more than one output should be shorted at a time, and the duration should not exceed one second.
Note 2: ICC is measured with all outputs open, and 4.5 V ap plied to all inputs.
IN74LS157
3
AC ELECTRICAL CHARACTERISTICS (TA=25°C, VCC = 5.0 V, CL = 15 pF, RL = 2 kΩ, tr =15
ns, tf = 6.0 ns)
Symbol Parameter Min Max Unit
tPLH Propagation Delay, Input A or B to Output Y 14 ns
tPHL Propagation Delay, Input A or B to Output Y 14 ns
tPLH Propagation Delay, Select to Output Y 23 ns
tPHL Propagation Delay, Select to Output Y 27 ns
tPLH Propagation Delay, Output Enable to Output Y 20 ns
tPHL Propagation Delay, Output Enable to Output Y 21 ns
Figure 1. Switching Waveforms Figure 2. Switching Waveforms
NOTES A. CL includes probe and jig capacitance.
B. All diodes are 1N916 or 1N3064.
Figure 3. Test Circuit
