TECHNICAL DATA IN74LS157 Quad 2-Input Data Selector/Multiplexer 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 ORDERING INFORMATION IN74LS157N Plastic IN74LS157D SOIC TA =0° to 70° C for all packages PIN ASSIGNMENT LOGIC DIAGRAM FUNCTION TABLE Inputs PIN 16 =VCC PIN 8 = GND Outputs Output Enable Select Y0-Y3 H X L L L A0-A3 L H B0-B3 X=don’t care A0-A3,B0-B3=the levels of the respective Data-Word Inputs 1 IN74LS157 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 5.25 V VCC Supply Voltage 4.75 VIH High Level Input Voltage 2.0 VIL Low Level Input Voltage 0.8 V IOH High Level Output Current -0.4 mA IOL Low Level Output Current 8.0 mA TA Ambient Temperature Range +70 °C 0 V DC ELECTRICAL CHARACTERISTICS over full operating conditions Guaranteed Limit Symbol Parameter Test Conditions Min Max Unit -1.5 V VIK Input Clamp Voltage VCC = min, IIN = -18 mA VOH High Level Output Voltage VCC = min, IOH = -0.4 mA VOL Low Level Output Voltage VCC = min, IOL = 4 mA 0.4 VCC = min, IOL = 8 mA 0.5 VCC = max for pins 1,15 40 VIN = 2.7 V A or B input 20 VCC = max for pins 1,15 0.2 VIN = 7.0 V A or B input 0.1 VCC = max for pins 1,15 -0.8 VIN = 0.4 V A or B input -0.4 IIH IIL High Level Input Current Low Level Input Current IO Output Short Circuit Current VCC = max, VO = 0 V (Note 1) ICC Supply Current VCC = max (Note 2) 2.7 -20 V V µA mA mA -100 mA 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 applied to all inputs. 2 IN74LS157 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 3